Time Zone Converter

Planning a call across three or four countries usually means running the same conversion over and over, once per teammate, then holding all those numbers in your head while you pick a time nobody hates. This puts the whole thing in one view. Enter the moment you're thinking about, tell it which zone that clock belongs to, and every city you care about lines up below it, each showing its own local time for that exact instant. It's free, it runs entirely in your browser, and it colors each card so you can see who would be at their desk and who would be fast asleep.

That last part is the piece most single from-to converters skip. They'll happily tell you 4pm in New York is 9pm in London, then leave you to work out on your own that 9pm is a lousy time to ask a Londoner onto a call. Here the London card glows amber, Tokyo goes dark for the middle of the night, and anyone sitting in normal work hours turns green. You read the good slot off the board instead of reasoning it out one person at a time.

And because the whole board sits behind a share link, you can hand the exact setup to the group. One URL, and everyone opens the same board, no screenshot, no retyping.

1. Set the meeting time. Type or pick the date and time, or hit Now to drop in the current moment. Whatever you enter is the wall-clock time in the base zone, so 9:00 AM with New York as the base means 9am in New York.
2. Choose the base zone in "Read this time as." This is the zone the time you typed belongs to. A colleague says "let's say 2pm my time" and they're in Berlin? Set the base to Berlin.
3. Add the places you're comparing. Use "Add a place to compare" and pick a city. Add as many as you need, the whole team, a client, family in another country. Each one appears as its own card.
4. Read the colors. Green means that city is in normal working hours for the instant you chose, amber means early morning or evening, gray means the middle of the night. Scan the row and the workable time is obvious.
5. Re-anchor if you want. Hit "Set as base" on any card to view the same real moment from that city's point of view, handy when you switch whose 9am you're building around. The ✕ on a card drops a zone you no longer need.
6. Share or copy. "Copy all zones" grabs a clean text block for a message or a calendar note. The Share button copies a link that reopens this exact board for whoever you send it to.

No convert button, no reload. Change the time, swap a city, flip between 12 and 24 hour, and every card updates as you go. A small line under the board shows the same instant in plain UTC too, a neutral reference to paste when a team is so spread out that no single local clock feels official.

A raw conversion answers "what time is it there." The harder question, the one you actually have when scheduling, is whether that's a reasonable time to make someone show up. So each card carries a colored dot and a short label. Roughly 9 to 5 shows as working hours. The edges either side of that are marked early or late, and the deep night is flagged as asleep. Those bands are loose on purpose, someone's real day might open at 8 or run to 7, so treat the colors as a guide rather than gospel. What they mainly do is save you time, so instead of squinting at "11pm" and mentally deciding whether that's cruel, you see the card is gray and nudge the meeting.

This is where planning across five zones stops being a slog. Push the time forward an hour at a time, watch the colors shift, and when the greens overlap for everyone, or come as close as a spread-out team ever gets, that's your slot.

Most converters quietly use whatever offset is in effect right now, which is fine for a call today and wrong the second you schedule across a daylight saving switch. Take a standing meeting between London and New York. Most of the year they're five hours apart. But the US springs forward in early March and Europe waits until the end of the month, so for two or three weeks every spring the real gap is four hours, not five. Book that March call off today's offset and someone ends up alone on the line wondering where everyone went.

This tool converts for the date you pick, not for today, so the offset you see is the one that'll genuinely be in force. That's the whole reason you enter a date and not just a time.

Then there's the quieter version. A place that never touches its clocks still isn't a fixed distance from you. Arizona and most of Asia hold one offset all year, which sounds simpler, and for them it is. But Phoenix standing still doesn't stop the gap between Phoenix and New York from moving twice a year, because New York moves. "They don't do daylight saving" and "the difference never changes" are two separate claims, and confusing them is how a call ends up an hour off even though neither side changed a clock.

Abbreviations feel convenient and cause quiet trouble. Someone writes "3pm EST" in July meaning East Coast time, but EST is Eastern Standard Time, the winter offset, and from March to November the East Coast actually runs on EDT, an hour off from what they meant. A few abbreviations are outright reused, too. "CST" is Central Standard Time in Chicago and China Standard Time in Shanghai, the same three letters for two clocks fourteen hours apart.

So this tool works from IANA zone names like America/New_York and Asia/Tokyo, the same set your phone already trusts. A name like that isn't a single offset, it's the full rulebook: one offset in winter, another in summer, and the exact dates it flips. When you propose a time to people, name the city, "9am Los Angeles," rather than "9am PST," since a city name points to exactly one clock.

Half-hour zones belong here too, since they're where mental math falls apart. India runs on UTC+5:30, Nepal on +5:45, parts of Australia on +9:30. Guess "India's about ten and a half hours ahead" and you're right only if you keep that stray half hour, the exact bit people drop. The board carries the odd fractions for you, so Kathmandu comes back on the 45 rather than rounded to something clean and wrong.