Time zone guides
Telling and translating time across the world, explained simply.
Everything about reading and translating time across the world: how time zones and UTC offsets work, why daylight saving quietly shifts your recurring meetings, what the abbreviations like EST, CET and IST actually mean, and the best windows to call or meet between specific cities and countries.
How to use multiple time zones in Apple Calendar
Apple Calendar hides time zone support in Settings. How to turn it on, what Floating means, and where it stops.
Time Zone GuidesHow to show multiple time zones in your Mac menu bar
macOS shows one time zone in the menu bar. How to add more, what the built-in Clock app does instead, and how many clocks actually fit.
Time Zone GuidesHow to schedule a meeting across time zones
Find the overlap, respect working hours, and dodge the daylight-saving traps - a repeatable way to schedule across zones.
Time Zone GuidesUTC vs GMT: what's the difference?
They show the same time, but one is a time zone and the other a time standard. Which to use for scheduling, and why it matters.
Time Zone GuidesDST 2026: every country's clock-change dates
When the clocks change in 2026, country by country, and why the US and Europe don't switch on the same day.
Time Zone GuidesBest time to call India from the USA
India is half a day ahead, so call in your morning to catch their evening. Exact windows for the East, Central and West coasts.
Time Zone GuidesHow many time zones are there in the world?
24 in theory, about 38 in practice. Why half-hour and 45-minute offsets push the real count past two dozen.
Time Zone GuidesWhat is UTC? A plain-English guide for scheduling
UTC is the single clock the world agrees on, and every time zone is just an offset from it. Why it matters for scheduling.
Time Zone GuidesWhy some time zones are 30 or 45 minutes off
India runs on UTC+5:30 and Nepal on UTC+5:45. Why a few countries use half-hour and quarter-hour offsets.
Time Zone GuidesWhat do PST, EST, and CET mean? Abbreviations explained
PST, EST, CET and the rest decoded, why the same letters mean different offsets worldwide, and what to use instead.
Time Zone GuidesEST vs EDT: why the abbreviation changes twice a year
EST is winter (UTC-5), EDT is summer (UTC-4): same place, one hour apart. Which is in effect, and when to write ET.
Time Zone GuidesWhat is IST (India Standard Time)?
IST is UTC+5:30: one fixed clock for all of India and Sri Lanka, with no daylight saving.
Time Zone GuidesWhat is EST (Eastern Standard Time)?
EST is UTC-5, the winter clock of the US East Coast. Who uses it and how it differs from EDT and ET.
Time Zone GuidesWhat is PST (Pacific Standard Time)?
PST is UTC-8, the winter clock of the US and Canada West Coast. How it differs from PDT and PT.
Time Zone GuidesWhat is CET (Central European Time)?
CET is UTC+1, the winter clock for most of continental Europe. In summer it shifts to CEST (UTC+2).
Time Zone Guides12-hour vs 24-hour time: how to avoid mix-ups
One clock uses AM and PM, the other runs 00:00 to 23:59. How to convert, and dodge 12 AM / 12 PM mix-ups.
Time Zone GuidesDoes daylight saving time affect my meetings?
Yes, and the riskiest weeks are late March and late October, when recurring cross-border calls silently drift.
Time Zone GuidesWhy New York and London are 4 hours apart every March
Usually 5 hours apart, but for three weeks each March daylight saving falls out of sync and the gap drops to 4.
Time Zone GuidesSpring forward, fall back: what it means for global teams
The daylight saving mnemonic explained, plus why teams lose their overlap for a few weeks twice a year.
Time Zone GuidesWhich countries don't observe daylight saving time?
Most of the world skips it. Asia, Africa, the Middle East, Hawaii, Arizona and much of Australia stay on one clock.
Time Zone GuidesHow to schedule recurring meetings that survive daylight saving
Recurring international calls drift when one country changes clocks before the other. Three ways to anchor them.
Time Zone GuidesBest time to call the Philippines from the USA
The Philippines is 12-16 hours ahead of the US. Call early in your morning to reach Manila in the evening, with windows for every coast.
Time Zone GuidesBest time to call the USA from India
The US is 9.5-13.5 hours behind India. Call around 6-9 PM IST to catch the US morning.
Time Zone GuidesBest time to call the UK from the USA
The UK is 5 hours ahead of US Eastern and 8 ahead of Pacific. Call in your morning to catch the UK afternoon.
Time Zone GuidesBest time to call Australia from the USA
Sydney is about 14 hours ahead of US Eastern, so the best time to call is your afternoon, their next morning.
Time Zone GuidesBest time to call India from the UK
India is 4.5 hours ahead of the UK in summer, 5.5 in winter. Call in your morning to reach their afternoon.
Time Zone GuidesBest time to call Australia from the UK
Sydney is 9-11 hours ahead of the UK. Call around 7-9 AM to catch the Sydney evening.
Time Zone GuidesLondon to New York time difference
London is 5 hours ahead of New York most of the year. Offset tables, best meeting windows, and the brief 4-hour DST gap.
Time Zone GuidesNew York to Tokyo time difference
Tokyo runs 13 hours ahead of New York in summer, 14 in winter. Worked conversions and the one window that works.
Time Zone GuidesSan Francisco to London time difference
London runs 8 hours ahead of San Francisco, so your morning lines up with London's late afternoon for a clean daily window.
Time Zone GuidesSydney to London time difference
Sydney is 9-11 hours ahead of London, swinging with opposite-season daylight saving. The reliable overlap is the day's edges.
Time Zone GuidesLos Angeles to London time difference
London runs 8 hours ahead of Los Angeles, so an LA morning meets a London afternoon. Exact conversions and the spring catch.
Time Zone GuidesDubai to London time difference
Dubai is 4 hours ahead of London in winter, 3 in summer. Offset tables, worked conversions and the best meeting window.
Time Zone GuidesEST to IST converter: what time is it in India?
India runs 10.5 hours ahead of EST, so 9 AM EST is 7:30 PM in India. Convert any Eastern hour to IST instantly.
Time Zone GuidesEST to PST converter: Eastern to Pacific time
US Eastern is always 3 hours ahead of Pacific. The exact conversions and the best coast-to-coast meeting window.
Time Zone GuidesGMT to EST converter: UK to US Eastern time
GMT runs 5 hours ahead of US Eastern, so noon in the UK is 7:00 AM EST. Conversion tables, best overlap, and the DST catch.
Time Zone GuidesCET to EST converter: Central European to US Eastern
CET is 6 hours ahead of EST: noon CET is 6 AM EST. Conversion tables and the best European-afternoon overlap.
Time Zone GuidesPST to IST converter: US Pacific to India time
India is 13.5 hours ahead of US Pacific (12.5 in summer). 9 AM PST is 10:30 PM IST, with full conversion tables.
Time Zone GuidesGMT to IST converter: UK to India time
India runs 5.5 hours ahead of GMT, so noon in London is 5:30 PM in India. Offset and conversion tables.
Time Zone GuidesUSA-India time zone difference (overlap windows)
India runs 9.5-13.5 hours ahead of the US, so a remote team gets one overlap: your morning, India's evening.
Time Zone GuidesUSA-Philippines time zone difference
The Philippines is 12-13 hours ahead of US Eastern and 15-16 ahead of Pacific, with one narrow early-morning overlap.
Time Zone GuidesUSA-Mexico time zone difference
Mexico City matches US Central in winter and sits an hour behind in summer, giving a near-full shared working day.
Time Zone GuidesUSA-UK time zone difference
The UK is 5 hours ahead of US Eastern and 8 ahead of Pacific most of the year, with worked conversions and the best window.
Time Zone GuidesEurope-Australia time zone difference (and how to meet anyway)
Central Europe sits 8-10 hours behind eastern Australia, with almost no shared workday. The offsets and the two usable windows.
Time Zone GuidesUSA-Colombia time zone difference
Colombia matches US Eastern in winter and runs an hour behind in summer, giving US teams a nearly complete shared workday.
Time Zone GuidesUSA-Germany time zone difference
Germany runs 6 to 9 hours ahead of the US depending on your coast. The exact gap and the best shared meeting window.
Time Zone GuidesUSA-Japan time zone difference
Japan runs 13 to 17 hours ahead of the US, one of the hardest pairs to find a live overlap for, and what to do instead.
Time Zone GuidesUSA-Canada time zone difference
For most of the border there's no difference at all, Canada shares US time zones. The real exceptions worth knowing.
Time Zone GuidesWhy doesn't Arizona observe daylight saving time?
Arizona skips DST entirely, except the Navajo Nation, which skips the exception again on the Hopi Reservation.
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