Timezone converter
GMT to JST currently uses Greenwich Mean Time in Europe/London and Japan Time in Asia/Tokyo as the live reference pair, with a +9h live gap. GMT to JST matters whenever London and Tokyo need to coordinate across a +9h gap. The GMT side covers United Kingdom and Ivory Coast, while JST covers Japan — that country mix is the practical reason this conversion shows up in calendars rather than the abstract offset math.
Offset math, DST behavior, and city coverage on both sides are refreshed from the live timezone dataset during the page revalidation window.
From
Greenwich Mean Time
Europe/London · GMT+0 +00:00
Major markets in this grouping include London, Abidjan, Bamako, Dakar.
To
Japan Time
Asia/Tokyo · GMT+9 +09:00
Major markets in this grouping include Tokyo, Yokohama, Osaka, Nagoya.
Current gap
+9h
GMT +00:00 vs JST +09:00
9-to-5 overlap
No shared block
Meetings usually need an early or late handoff.
Representative countries
United Kingdom, Ivory Coast, and Mali / Japan
Based on the busiest city and zone usage found in the current dataset.
GMT (London, +00:00) to JST (Tokyo, +09:00) is currently a +9h conversion. Live coverage on the GMT side is anchored by London, Abidjan, Bamako, and Dakar; the JST side draws from Tokyo, Yokohama, Osaka, and Nagoya.
GMT to JST matters whenever London and Tokyo need to coordinate across a +9h gap. The GMT side covers United Kingdom and Ivory Coast, while JST covers Japan — that country mix is the practical reason this conversion shows up in calendars rather than the abstract offset math.
GMT means Greenwich, UK winter civil time, Iceland, Atlantic islands, and West African zero-offset countries; watch UK bank holidays, Irish public holidays, and West African national calendars. JST is grounded here by Japan. The curated side is where most same-offset duplication risk is removed, because it names the civil calendar and operating context users actually mean.
This pair runs between Europe or Africa and Asia or the Pacific. With +9h between them, the late European morning often catches the early Asian evening, which is the practical window for cross-region operations and travel planning.
GMT follows seasonal clock changes through Europe/London, while JST stays on a fixed offset year-round. That asymmetry is the real differentiator on this page: the gap widens or narrows by an hour twice a year, so calendar invites scheduled in one season often look wrong in the other.
GMT and JST sit exactly 9h apart, which leaves no shared 9-to-5 block. Live meetings have to bend one side's day, so most teams settle for one of two narrow windows: very early on the late side, or very late on the early side. That makes async messages, recorded standups, and clear handoff notes more valuable than calendar invites.
Reference zone, current offsets, country and city anchors, overlap math, and date-shift answers for GMT to JST.
Reference pair
Europe/London -> Asia/Tokyo
Live offsets
GMT +00:00 vs JST +09:00
Meaning split
Greenwich Mean Time / Japan Time
Country anchors
United Kingdom, Ivory Coast, and Mali -> Japan
City anchors
London, Abidjan, Bamako, Dakar -> Tokyo, Yokohama, Osaka, Nagoya
Workday overlap
No strict 9-to-5 overlap in the current offset state
Morning answer
9 AM GMT = 6:00 PM JST, same day
Evening answer
6 PM GMT = 3:00 AM JST, next day
Same-offset labels can share the same hour while still landing in different countries, calendars, cities, and workday windows. These notes show the practical context behind this conversion.
GMT to JST is pinned to Europe/London -> Asia/Tokyo, with the shorthand labels shown as context. The city anchors are London, Abidjan, Bamako, Dakar on the GMT side and Tokyo, Yokohama, Osaka, Nagoya on the JST side, with +9h between the live reference zones.
The 12 popular-hour answers include 7 same-day conversions, 5 next-day conversions, and 0 previous-day conversions. That distribution is what separates this page from a static offset chart.
Nearby labels sharing a current offset include UTC (From side), WEST (From side), WET (From side), GMT+9 (To side), KST (To side), PWT (To side). They may match mathematically, but their country calendars, city anchors, and common search intent differ from this exact pair.
GMT: United Kingdom (GB); 863 mapped cities; capital London; English; GBP British pound | GMT: Ivory Coast (CI); 183 mapped cities; capital Yamoussoukro; French; XOF West African CFA franc | GMT: Mali (ML); 59 mapped cities; capital Bamako; French; XOF West African CFA franc | GMT: Senegal (SN); 70 mapped cities; capital Dakar; French; XOF West African CFA franc | GMT: Ghana (GH); 102 mapped cities; capital Accra; English; GHS Ghanaian cedi | JST: Japan (JP); 1296 mapped cities; capital Tokyo; Japanese; JPY Japanese yen
Offset behavior, DST gap changes, local calendar evidence, and the day-shift pattern across the most common conversion hours.
GMT/JST is a long-haul handoff gap: Europe/London currently reads +00:00, Asia/Tokyo reads +09:00, and the live delta is +9h. This class decides whether the page behaves like a same-day planner or a handoff planner.
Europe/London changes from +00:00 (GMT+0) to +01:00 (GMT+1) on March 28, 2027 at about 2:00 AM.
No country holiday snapshot is attached to this exact pair yet, so the page leans on city anchors, IANA zones, offsets, and the live conversion table instead of pretending a local calendar exists.
Across the 12 popular-hour answers, this pair has 7 same-day answers, 5 next-day answers, 0 previous-day answers. That mix is specific to the current Europe/London -> Asia/Tokyo relationship and helps users see whether dates must be written explicitly in invites, travel plans, and release schedules.
Same-offset converter clusters can look identical if the page only shows a numeric offset. This audit states whether the route should be indexed, which canonical peer it follows when consolidated, and what pair-specific evidence keeps the page useful.
This pair remains indexable because the route has enough pair-specific context: Europe/London -> Asia/Tokyo, country anchors, city anchors, calendar notes, and day-shift examples.
GMT and JST are not currently a same-offset pair; the live delta is +9h. Same-offset neighbors are still listed because users often confuse nearby abbreviations.
UTC (From side, +00:00), WEST (From side, +00:00), WET (From side, +00:00), GMT+9 (To side, +09:00), KST (To side, +09:00), PWT (To side, +09:00) The page keeps these labels visible so SGT/HKT/GST-style clusters do not blur into one generic offset page.
GMT/JST uses 7 same-day answers, 5 next-day answers, 0 previous-day answers; 0h strict workday overlap; source zones Europe/London and Asia/Tokyo; country anchors United Kingdom, Ivory Coast, and Mali -> Japan.
Common places, calendars, markets, languages, and operating contexts behindGMT and JST.
GMT
GMT is not just a country clock. In this dataset it spans London, Dublin, Reykjavik, West Africa, Atlantic islands, and reference-style public schedules. It is commonly used as a source label in broadcasts, aviation-adjacent notices, release notes, and public event listings, but software and contracts often prefer UTC or a precise IANA zone.
GMT
For UK-facing planning, GMT needs a seasonal caveat: Europe/London can display British Summer Time while a sender still casually writes GMT. That is why converter pages using GMT should keep the exact reference zone visible instead of pretending the three-letter label is always enough.
JST
JST is Japan civil time, centered on Tokyo, Yokohama, Osaka, Nagoya, Sapporo, Fukuoka, and the rest of the Japanese domestic timetable. The useful context is Japan's no-DST posture, yen-denominated business cycles, Tokyo Stock Exchange timing, rail and aviation punctuality, anime/game/media release schedules, and holiday clusters such as Golden Week and year-end closures.
JST
A JST conversion is often searched by teams coordinating with Japan specifically, not merely UTC+9. Product launches, live streams, travel arrivals, and support handoffs should account for Japanese business etiquette, local public holidays, and the difference between Japan's stable clock and regions where daylight saving changes the counterpart offset.
Same-offset conversions can still land in different public-holiday, language, currency, and city-anchor contexts. These rows use the country profile and holiday snapshots behind each side of the pair.
GMT
863 mapped city anchors; zones Europe/London.capital London; English; GBP British pound
Holiday snapshot: New Year's Day (Jan 1, Public) · 2 January (Jan 2, Public) · Saint Patrick's Day (Mar 17, Public) · Good Friday (Apr 3, Public) · Easter Monday (Apr 6, Public)
GMT
183 mapped city anchors; zones Africa/Abidjan.capital Yamoussoukro; French; XOF West African CFA franc
Holiday snapshot: No holiday snapshot attached for the current year.
GMT
59 mapped city anchors; zones Africa/Bamako.capital Bamako; French; XOF West African CFA franc
Holiday snapshot: No holiday snapshot attached for the current year.
GMT
70 mapped city anchors; zones Africa/Dakar.capital Dakar; French; XOF West African CFA franc
Holiday snapshot: No holiday snapshot attached for the current year.
GMT
102 mapped city anchors; zones Africa/Accra.capital Accra; English; GHS Ghanaian cedi
Holiday snapshot: New Year's Day (Jan 1, Public) · Constitution Day (Jan 7, Public) · Independence Day (Mar 6, Public) · Good Friday (Apr 3, Public) · Easter Monday (Apr 6, Public)
JST
1,296 mapped city anchors; zones Asia/Tokyo.capital Tokyo; Japanese; JPY Japanese yen
Holiday snapshot: New Year's Day (Jan 1, Public) · Coming of Age Day (Jan 12, Public) · Foundation Day (Feb 11, Public) · The Emperor's Birthday (Feb 23, Public) · Vernal Equinox Day (Mar 20, Public)
These are the labels most likely to be confused with either side of this conversion. A matching UTC offset does not mean the same country, calendar, market, source convention, or user intent.
GMT and UTC match on offset right now, but the page should not collapse them: they carry different city anchors, country calendars, currencies, holidays, and user intent.
GMT and BST are close enough to be confused in search, but they are not the same clock label and should be pinned to exact IANA zones.
GMT and WEST match on offset right now, but the page should not collapse them: they carry different city anchors, country calendars, currencies, holidays, and user intent.
GMT and WET match on offset right now, but the page should not collapse them: they carry different city anchors, country calendars, currencies, holidays, and user intent.
GMT and AZOST are close enough to be confused in search, but they are not the same clock label and should be pinned to exact IANA zones.
GMT and AZOT are close enough to be confused in search, but they are not the same clock label and should be pinned to exact IANA zones.
JST and GMT+9 match on offset right now, but the page should not collapse them: they carry different city anchors, country calendars, currencies, holidays, and user intent.
JST and KST match on offset right now, but the page should not collapse them: they carry different city anchors, country calendars, currencies, holidays, and user intent.
JST and PWT match on offset right now, but the page should not collapse them: they carry different city anchors, country calendars, currencies, holidays, and user intent.
JST and WIT match on offset right now, but the page should not collapse them: they carry different city anchors, country calendars, currencies, holidays, and user intent.
JST and YAKT match on offset right now, but the page should not collapse them: they carry different city anchors, country calendars, currencies, holidays, and user intent.
JST and ACWST are close enough to be confused in search, but they are not the same clock label and should be pinned to exact IANA zones.
Abbreviations with the same UTC offset can still represent different countries, cities, currencies, languages, and civil-time histories. This roster keeps theGMT to JST page grounded in those concrete places.
GMT: United Kingdom (GB); 863 mapped cities; zones Europe/London; city anchors London (Europe/London, pop 8,961,989), Birmingham (Europe/London, pop 1,157,603), Glasgow (Europe/London, pop 626,410), Manchester (Europe/London, pop 568,996); official United Kingdom of Great Britain and Northern Ireland; capital London; region Europe; subregion Northern Europe; population 69,281,437; area 244,376 km2; languages English; currency GBP British pound.
GMT: Ivory Coast (CI); 183 mapped cities; zones Africa/Abidjan; city anchors Abidjan (Africa/Abidjan, pop 6,321,017), Abobo (Africa/Abidjan, pop 1,340,083), Bouaké (Africa/Abidjan, pop 832,371), Korhogo (Africa/Abidjan, pop 440,926); official Republic of Côte d'Ivoire; capital Yamoussoukro; region Africa; subregion Western Africa; population 31,719,275; area 322,463 km2; languages French; currency XOF West African CFA franc.
GMT: Mali (ML); 59 mapped cities; zones Africa/Bamako; city anchors Bamako (Africa/Bamako, pop 4,227,569), Sikasso (Africa/Bamako, pop 349,324), Koutiala (Africa/Bamako, pop 218,031), Ségou (Africa/Bamako, pop 205,787); official Republic of Mali; capital Bamako; region Africa; subregion Western Africa; population 22,395,489; area 1,240,192 km2; languages French; currency XOF West African CFA franc.
GMT: Senegal (SN); 70 mapped cities; zones Africa/Dakar; city anchors Dakar (Africa/Dakar, pop 2,646,503), Touba (Africa/Dakar, pop 1,120,824), Pikine (Africa/Dakar, pop 874,062), Guédiawaye (Africa/Dakar, pop 329,659); official Republic of Senegal; capital Dakar; region Africa; subregion Western Africa; population 18,593,258; area 196,722 km2; languages French; currency XOF West African CFA franc.
GMT: Ghana (GH); 102 mapped cities; zones Africa/Accra; city anchors Kumasi (Africa/Accra, pop 2,544,530), Accra (Africa/Accra, pop 1,963,264), Tamale (Africa/Accra, pop 464,316), Takoradi (Africa/Accra, pop 389,114); official Republic of Ghana; capital Accra; region Africa; subregion Western Africa; population 33,742,380; area 238,533 km2; languages English; currency GHS Ghanaian cedi.
JST: Japan (JP); 1296 mapped cities; zones Asia/Tokyo; city anchors Tokyo (Asia/Tokyo, pop 9,733,276), Yokohama (Asia/Tokyo, pop 3,777,491), Osaka (Asia/Tokyo, pop 2,753,862), Nagoya (Asia/Tokyo, pop 2,332,176); official Japan; capital Tokyo; region Asia; subregion Eastern Asia; population 123,210,000; area 377,930 km2; languages Japanese; currency JPY Japanese yen.
Same-offset converter pages can look deceptively alike. These records pin the page to the exact abbreviations, IANA zones, countries, and city anchors behind GMT and JST.
GMT (gmt) is not marked ambiguous in the abbreviation catalog. Meaning records: Greenwich Mean Time at UTC+00:00; listed zones Africa/Abidjan; Africa/Bamako; Africa/Bissau; Africa/Conakry; Africa/Dakar; America/Danmarkshavn; Africa/Freetown; Atlantic/St Helena; Africa/Accra; Africa/Lome; Africa/Monrovia; Africa/Nouakchott; source label Greenwich Mean Time - Abidjan, Abobo, Bouaké, Korhogo.
GMT currently maps to 8 country footprints in the converter dataset: United Kingdom (GB), Ivory Coast (CI), Mali (ML), Senegal (SN), Ghana (GH), Burkina Faso (BF), Togo (TG), Guinea (GN). The footprint spans 8 IANA zones across 10 city anchors.
GMT city anchors in this indexed page family: London [london-GB, GB, Europe/London, pop 8,961,989]; Abidjan [abidjan-CI, CI, Africa/Abidjan, pop 6,321,017]; Bamako [bamako-ML, ML, Africa/Bamako, pop 4,227,569]; Dakar [dakar-SN, SN, Africa/Dakar, pop 2,646,503]; Kumasi [kumasi-GH, GH, Africa/Accra, pop 2,544,530]; Ouagadougou [ouagadougou-BF, BF, Africa/Ouagadougou, pop 2,415,266]; Lomé [lome-TG, TG, Africa/Lome, pop 2,188,376]; Accra [accra-GH, GH, Africa/Accra, pop 1,963,264]; Conakry [conakry-GN, GN, Africa/Conakry, pop 1,928,389]; Camayenne [camayenne-GN, GN, Africa/Conakry, pop 1,871,242].
GMT: United Kingdom (GB); 863 mapped cities; zones Europe/London; city anchors London (Europe/London, pop 8,961,989), Birmingham (Europe/London, pop 1,157,603), Glasgow (Europe/London, pop 626,410), Manchester (Europe/London, pop 568,996); official United Kingdom of Great Britain and Northern Ireland; capital London; region Europe; subregion Northern Europe; population 69,281,437; area 244,376 km2; languages English; currency GBP British pound. GMT: Ivory Coast (CI); 183 mapped cities; zones Africa/Abidjan; city anchors Abidjan (Africa/Abidjan, pop 6,321,017), Abobo (Africa/Abidjan, pop 1,340,083), Bouaké (Africa/Abidjan, pop 832,371), Korhogo (Africa/Abidjan, pop 440,926); official Republic of Côte d'Ivoire; capital Yamoussoukro; region Africa; subregion Western Africa; population 31,719,275; area 322,463 km2; languages French; currency XOF West African CFA franc. GMT: Mali (ML); 59 mapped cities; zones Africa/Bamako; city anchors Bamako (Africa/Bamako, pop 4,227,569), Sikasso (Africa/Bamako, pop 349,324), Koutiala (Africa/Bamako, pop 218,031), Ségou (Africa/Bamako, pop 205,787); official Republic of Mali; capital Bamako; region Africa; subregion Western Africa; population 22,395,489; area 1,240,192 km2; languages French; currency XOF West African CFA franc. GMT: Senegal (SN); 70 mapped cities; zones Africa/Dakar; city anchors Dakar (Africa/Dakar, pop 2,646,503), Touba (Africa/Dakar, pop 1,120,824), Pikine (Africa/Dakar, pop 874,062), Guédiawaye (Africa/Dakar, pop 329,659); official Republic of Senegal; capital Dakar; region Africa; subregion Western Africa; population 18,593,258; area 196,722 km2; languages French; currency XOF West African CFA franc. GMT: Ghana (GH); 102 mapped cities; zones Africa/Accra; city anchors Kumasi (Africa/Accra, pop 2,544,530), Accra (Africa/Accra, pop 1,963,264), Tamale (Africa/Accra, pop 464,316), Takoradi (Africa/Accra, pop 389,114); official Republic of Ghana; capital Accra; region Africa; subregion Western Africa; population 33,742,380; area 238,533 km2; languages English; currency GHS Ghanaian cedi.
JST (jst) is not marked ambiguous in the abbreviation catalog. Meaning records: Japan Time at UTC+09:00; listed zones Asia/Tokyo; source label Japan Time - Tokyo, Yokohama, Osaka, Nagoya.
JST currently maps to 1 country footprint in the converter dataset: Japan (JP). The footprint spans 1 IANA zone across 10 city anchors.
JST city anchors in this indexed page family: Tokyo [tokyo-JP, JP, Asia/Tokyo, pop 9,733,276]; Yokohama [yokohama-JP, JP, Asia/Tokyo, pop 3,777,491]; Osaka [osaka-JP, JP, Asia/Tokyo, pop 2,753,862]; Nagoya [nagoya-JP, JP, Asia/Tokyo, pop 2,332,176]; Sapporo [sapporo-JP, JP, Asia/Tokyo, pop 1,973,832]; Fukuoka [fukuoka-JP, JP, Asia/Tokyo, pop 1,612,392]; Kawasaki [kawasaki-JP, JP, Asia/Tokyo, pop 1,538,262]; Kobe [kobe-JP, JP, Asia/Tokyo, pop 1,525,152]; Kyoto [kyoto-JP, JP, Asia/Tokyo, pop 1,463,723]; Saitama [saitama-JP, JP, Asia/Tokyo, pop 1,324,854].
JST: Japan (JP); 1296 mapped cities; zones Asia/Tokyo; city anchors Tokyo (Asia/Tokyo, pop 9,733,276), Yokohama (Asia/Tokyo, pop 3,777,491), Osaka (Asia/Tokyo, pop 2,753,862), Nagoya (Asia/Tokyo, pop 2,332,176); official Japan; capital Tokyo; region Asia; subregion Eastern Asia; population 123,210,000; area 377,930 km2; languages Japanese; currency JPY Japanese yen.
GMT started as Greenwich Mean Time and now lives a double life: a civil-time label still used by the UK and parts of West Africa in winter, and a casual synonym for UTC in broadcasting and public schedules. The two roles overlap most of the time, but precise work treats them as distinct. The busiest cities using GMT in the current catalog are London, Abidjan, Bamako, Dakar, and Kumasi. The lead live reference on this page is London (Europe/London), currently at +00:00 (GMT+0). Those cities are what give GMT its actual feel rather than the abstract offset. GMT has a local identity beyond its offset: Greenwich, UK winter civil time, Iceland, Atlantic islands, and West African zero-offset countries. Calendar signals such as UK bank holidays, Irish public holidays, West African national calendars, and Icelandic no-DST scheduling and operational signals such as broadcast timestamps, public event listings, shipping and aviation-adjacent notices, and release notes written for a general audience are why this abbreviation should not be flattened into a same-offset neighbor. GMT currently shows +00:00, but Europe/London observes seasonal clock changes — the next transition is around March 28, 2027. That means the offset on this page is a snapshot, not a permanent fact, so long-range scheduling should pin the underlying IANA zone instead of the abbreviation.
GMT is not heavily split in the current catalog, but the short label still hides the underlying IANA zone and any future policy change. The safe pattern is to write the abbreviation for humans and the zone for machines. GMT behaves as a civil label in several places and as a public shorthand for UTC elsewhere; systems should store UTC or an IANA zone when the distinction matters. Not the same as GST, HKT, or SGT: GMT is a zero-offset reference family, not a Gulf, Hong Kong, or Singapore civil calendar. Europe/London has an upcoming offset change on March 28, 2027. After that point, GMT on this page will read a different UTC offset until the next transition, so any saved timestamp should anchor to the IANA zone rather than the abbreviation. GMT remains common in public schedules and broadcasting, while software teams almost always prefer UTC or an explicit IANA zone. The two are not technically identical (GMT is a civil-time label observed in winter; UTC is a continuously-corrected atomic standard), but they are close enough that mixing them rarely breaks anything in practice.
GMT should not be blindly swapped with nearby labels. Adjacent references in the catalog: UTC (+00:00, Often compared as a zero-offset reference); BST (+06:00, Shares the greenwich time family); WEST (+00:00, Currently sits on the same UTC offset); WET (+00:00, Currently sits on the same UTC offset); AZOST (-01:00, Runs on a nearby UTC offset); AZOT (-01:00, Runs on a nearby UTC offset).
GMT has 1 meaning record, offset range UTC+00:00 to UTC+02:00, labels Greenwich Mean Time, and 22 country footprints across 22 IANA zones.
JST is an Asian civil-time label, currently 9h ahead of UTC at +09:00. The lead reference is Tokyo, and the wider grouping reaches 1 country through 1 IANA zone. The busiest cities using JST in the current catalog are Tokyo, Yokohama, Osaka, Nagoya, and Sapporo. The lead live reference on this page is Tokyo (Asia/Tokyo), currently at +09:00 (GMT+9). Those cities are what give JST its actual feel rather than the abstract offset. JST is stable on Asia/Tokyo year-round, with no seasonal clock changes in the next year. That makes it a low-friction choice for recurring meetings and broadcast schedules — but software still prefers the IANA zone because governments can change civil-time rules independently of the short code.
JST resolves cleanly here, but Asian labels often share letters with American or European ones — IST is shared between India and Israel, for instance. Pinning Asia/Tokyo avoids that whole class of confusion. Asia/Tokyo does not show an offset change in the next year, which makes JST predictable for short-term scheduling. Predictable is not the same as permanent — civil-time rules still get changed by governments on relatively short notice. For precise work, the safest equivalent of JST is the exact IANA zone used by your city or system. Asia/Tokyo sits at +09:00, ahead of UTC, which means daily logs in this zone reach a new calendar date before UTC does — a small detail that breaks date-based reporting if missed.
JST should not be blindly swapped with nearby labels. Adjacent references in the catalog: GMT+9 (+09:00, Currently sits on the same UTC offset); KST (+09:00, Currently sits on the same UTC offset); PWT (+09:00, Currently sits on the same UTC offset); WIT (+09:00, Currently sits on the same UTC offset); YAKT (+09:00, Currently sits on the same UTC offset); ACWST (+08:45, Runs on a nearby UTC offset).
JST has 1 meaning record, offset range UTC+09:00, labels Japan Time, and 1 country footprint across 1 IANA zone.
GMT country anchor United Kingdom: The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in northwestern Europe, off the coast of the continental mainland. It comprises England, Scotland, Wales and Northern Ireland, with a population of over 69 million in 2024. The UK includes the island of Great Britain, the north-eastern part of the island of Ireland, and most of the smaller islands within the British Isles, covering 94,354 square miles (244,376 km2). It shares a land border with the Republic of Ireland and is surrounded by the Atlantic Ocean, the North Sea, the English Channel, the Celtic Sea and the Irish Sea, while maintaining sovereignty over the Crown Dependencies and the British Overseas Territories. The capital and largest city of England and the UK is London; Edinburgh, Cardiff and Belfast are the national capitals of Scotland, Wales and Northern Ireland. Source: Wikipedia.
JST country anchor Japan: Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asian mainland, it is bordered to the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea in the south. The Japanese archipelago consists of four major islands alongside 14,121 smaller islands. Japan is divided into 47 administrative prefectures and eight traditional regions, and around 75% of its terrain is mountainous and heavily forested, concentrating its agriculture and highly urbanized population along its eastern coastal plains. With a population of almost 123 million as of 2026, it is the world's 11th most populous country. Tokyo is the country's capital and largest city. Source: Wikipedia.
GMT is not just a country clock. In this dataset it spans London, Dublin, Reykjavik, West Africa, Atlantic islands, and reference-style public schedules. It is commonly used as a source label in broadcasts, aviation-adjacent notices, release notes, and public event listings, but software and contracts often prefer UTC or a precise IANA zone.
For UK-facing planning, GMT needs a seasonal caveat: Europe/London can display British Summer Time while a sender still casually writes GMT. That is why converter pages using GMT should keep the exact reference zone visible instead of pretending the three-letter label is always enough.
JST is Japan civil time, centered on Tokyo, Yokohama, Osaka, Nagoya, Sapporo, Fukuoka, and the rest of the Japanese domestic timetable. The useful context is Japan's no-DST posture, yen-denominated business cycles, Tokyo Stock Exchange timing, rail and aviation punctuality, anime/game/media release schedules, and holiday clusters such as Golden Week and year-end closures.
A JST conversion is often searched by teams coordinating with Japan specifically, not merely UTC+9. Product launches, live streams, travel arrivals, and support handoffs should account for Japanese business etiquette, local public holidays, and the difference between Japan's stable clock and regions where daylight saving changes the counterpart offset.
GMT/JST uses Europe/London -> Asia/Tokyo, offset delta +9h, overlap 0h, route /convert/gmt/jst/, and live abbreviation readings GMT+0/GMT+9.
GMT coverage on this page is led by London, United Kingdom, Abidjan, Ivory Coast, Bamako, Mali, and Dakar, Senegal, with 2 more in the live dataset. That mix is what makes GMT feel anchored to European working-day rhythms in practice rather than just an abbreviation on a chart. Local signals include broadcast timestamps, public event listings, and shipping and aviation-adjacent notices.
JST coverage is led by Tokyo, Japan, Yokohama, Japan, Osaka, Japan, and Nagoya, Japan, with 2 more anchoring the wider label family. Combined with the GMT side, this conversion ends up describing Europe-to-Asia trade calls, manufacturing supply-chain coordination, and joint-venture standups.
Adjust the time. Digits roll like an odometer, and the swap button flips the zones.
Same day in both places.
Quick conversions for 9 AM, noon, 3 PM, 6 PM, and 9 PM based on today's local calendar.
| GMT | JST | Day relation |
|---|---|---|
| 9:00 AM | 6:00 PMThu, Nov 5 | same day |
| 12:00 PM | 9:00 PMThu, Nov 5 | same day |
| 3:00 PM | 12:00 AMFri, Nov 6 | next day |
| 6:00 PM | 3:00 AMFri, Nov 6 | next day |
| 9:00 PM | 6:00 AMFri, Nov 6 | next day |
Quick conversions for 9 AM, noon, 3 PM, 6 PM, and 9 PM based on today's local calendar.
| JST | GMT | Day relation |
|---|---|---|
| 9:00 AM | 12:00 AMFri, Nov 6 | same day |
| 12:00 PM | 3:00 AMFri, Nov 6 | same day |
| 3:00 PM | 6:00 AMFri, Nov 6 | same day |
| 6:00 PM | 9:00 AMFri, Nov 6 | same day |
| 9:00 PM | 12:00 PMFri, Nov 6 | same day |
GMT to JST ranges from GMT 9:00 AM (which lands at JST 6:00 PM) through GMT 9:00 PM (JST 6:00 AM). Most of those slots fall on a different calendar day on the JST side, which is why this direction always needs explicit dates in invites and ticket comments — the time alone is not enough.
JST to GMT ranges from JST 9:00 AM (which lands at GMT 12:00 AM) through JST 9:00 PM (GMT 12:00 PM). With no clean 9-to-5 overlap between JST and GMT, both ends of this range push outside standard hours — useful for recorded standups and async work, awkward for live calls.
These direct answers are here for the exact-intent searches people actually use, like “10 AM GMT to JST” or “4 PM GMT in JST”.
8 AM GMT = 5:00 PM JST (17:00). On today's live calendar that lands on Thu, Nov 5 in JST, which means the answer is a same day conversion rather than a static offset lookup.
9 AM GMT = 6:00 PM JST (18:00). On today's live calendar that lands on Thu, Nov 5 in JST, which means the answer is a same day conversion rather than a static offset lookup.
10 AM GMT = 7:00 PM JST (19:00). On today's live calendar that lands on Thu, Nov 5 in JST, which means the answer is a same day conversion rather than a static offset lookup.
11 AM GMT = 8:00 PM JST (20:00). On today's live calendar that lands on Thu, Nov 5 in JST, which means the answer is a same day conversion rather than a static offset lookup.
12 PM GMT = 9:00 PM JST (21:00). On today's live calendar that lands on Thu, Nov 5 in JST, which means the answer is a same day conversion rather than a static offset lookup.
1 PM GMT = 10:00 PM JST (22:00). On today's live calendar that lands on Thu, Nov 5 in JST, which means the answer is a same day conversion rather than a static offset lookup.
2 PM GMT = 11:00 PM JST (23:00). On today's live calendar that lands on Thu, Nov 5 in JST, which means the answer is a same day conversion rather than a static offset lookup.
3 PM GMT = 12:00 AM JST (00:00). On today's live calendar that lands on Fri, Nov 6 in JST, which means the answer is a next day conversion rather than a static offset lookup.
4 PM GMT = 1:00 AM JST (01:00). On today's live calendar that lands on Fri, Nov 6 in JST, which means the answer is a next day conversion rather than a static offset lookup.
5 PM GMT = 2:00 AM JST (02:00). On today's live calendar that lands on Fri, Nov 6 in JST, which means the answer is a next day conversion rather than a static offset lookup.
6 PM GMT = 3:00 AM JST (03:00). On today's live calendar that lands on Fri, Nov 6 in JST, which means the answer is a next day conversion rather than a static offset lookup.
9 PM GMT = 6:00 AM JST (06:00). On today's live calendar that lands on Fri, Nov 6 in JST, which means the answer is a next day conversion rather than a static offset lookup.
The live gap is +9h right now, based on Europe/London at +00:00 and Asia/Tokyo at +09:00. Europe/London changes offset on March 28, 2027, so the gap moves to +8h after that transition.
There is no strict 9 AM to 5 PM overlap right now, so this pair is better for handoffs, travel planning, or async coordination than for midday meetings.
Europe/London
GMT+0 · +00:00
Asia/Tokyo
GMT+9 · +09:00
These are the busiest live references selected from the abbreviation families on this page.
| GMT | JST |
|---|---|
| 00:00 | 09:00 |
| 01:00 | 10:00 |
| 02:00 | 11:00 |
| 03:00 | 12:00 |
| 04:00 | 13:00 |
| 05:00 | 14:00 |
| 06:00 | 15:00 |
| 07:00 | 16:00 |
| 08:00 | 17:00 |
| 09:00 | 18:00 |
| 10:00 | 19:00 |
| 11:00 | 20:00 |
| 12:00 | 21:00 |
| 13:00 | 22:00 |
| 14:00 | 23:00 |
| 15:00 | 00:00 |
| 16:00 | 01:00 |
| 17:00 | 02:00 |
| 18:00 | 03:00 |
| 19:00 | 04:00 |
| 20:00 | 05:00 |
| 21:00 | 06:00 |
| 22:00 | 07:00 |
| 23:00 | 08:00 |
Countries represented here include United Kingdom, Ivory Coast, and Mali.
Countries represented here include Japan.
Once a conversion pair matters, people usually need a city page, compare page, or a broader browse surface next.
Interactive converter
Move from this static pair into the full timezone converter with more cities and abbreviations.
Compare city pairs
Use compare pages when the practical question is overlap, not just offset arithmetic.
World clock
Open live city clocks after narrowing the timezone pair you care about.
Browse city pages
Jump into the strongest city pages when you want location-specific timezone context.
