How accurate are the sunrise / sunset times?

Within roughly one minute for cities in mid-latitudes (most of the populated world). Accuracy degrades at extreme latitudes — above the Arctic Circle, the rapidly-changing sun angle can put real values 5-10 minutes off our approximation. For pinpoint accuracy at high latitudes, use a national meteorological service rather than this curve.

Why does Reykjavík show 0 hours in deep winter?

Because at 64 degrees north the sun barely clears the horizon for a few hours in late December, and our refraction model rounds those marginal cases down. In reality Reykjavík does see roughly 4 hours of dim daylight on the shortest day. The curve is correct in shape (massive seasonal swing) but conservative in the exact minimum.

Are the times in local time or UTC?

Daylight totals (in minutes) are timezone-invariant — they're just sunset minus sunrise. The displayed daily totals are computed for each calendar date in the city's civil time, so DST shifts don't cause artefacts in the curve.

Does this account for elevation or atmospheric refraction?

It accounts for standard atmospheric refraction (the reason the sun appears 0.833° above the geometric horizon at sunrise). It does not account for elevation or terrain; if you're at the bottom of a deep valley your effective sunrise is later than what's shown. For mountain or maritime calculations, use a dedicated solar-position library.

Daylight

A year of daylight

Each city gets a year-long daylight curve. Solstices are the peaks and troughs, equinoxes are the crossings. Pick a city below.

Last updated recently. The sun hub is a curated daylight-pattern index, not a full city sitemap. City pages use deterministic solar calculations from latitude, longitude, timezone, and date.

Daylight pattern map

Why these cities are in the daylight index

Hemisphere contrast

29 northern and 9 southern cities make the seasonal inversion visible instead of showing one repeated northern pattern.

Tropical baseline

8 low-latitude cities show the flatter daylight profile that makes Singapore, Lagos, Nairobi, and Lima different from London or Stockholm.

High-latitude swing

10 high-latitude cities show large summer/winter differences without relying only on polar examples.

Polar edge cases

Tromsø anchor midnight-sun and polar-night style searches where normal sunrise/sunset intuition breaks.

Questions

FAQ

How accurate are the sunrise / sunset times?: Within roughly one minute for cities in mid-latitudes (most of the populated world). Accuracy degrades at extreme latitudes — above the Arctic Circle, the rapidly-changing sun angle can put real values 5-10 minutes off our approximation. For pinpoint accuracy at high latitudes, use a national meteorological service rather than this curve.
Why does Reykjavík show 0 hours in deep winter?: Because at 64 degrees north the sun barely clears the horizon for a few hours in late December, and our refraction model rounds those marginal cases down. In reality Reykjavík does see roughly 4 hours of dim daylight on the shortest day. The curve is correct in shape (massive seasonal swing) but conservative in the exact minimum.
Are the times in local time or UTC?: Daylight totals (in minutes) are timezone-invariant — they're just sunset minus sunrise. The displayed daily totals are computed for each calendar date in the city's civil time, so DST shifts don't cause artefacts in the curve.
Does this account for elevation or atmospheric refraction?: It accounts for standard atmospheric refraction (the reason the sun appears 0.833° above the geometric horizon at sunrise). It does not account for elevation or terrain; if you're at the bottom of a deep valley your effective sunrise is later than what's shown. For mountain or maritime calculations, use a dedicated solar-position library.

A year of daylight

Why these cities are in the daylight index

FAQ

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A year of daylight

Why these cities are in the daylight index

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