A Telegram timezone bot that converts one time for everyone in the chat

Scheduling across zones fails in a specific way: somebody writes a time, everybody else silently assumes it is theirs, and one person joins an hour early. Posting UTC helps and nobody does it, because converting in your head is exactly the friction that caused the problem.

WhenIsItBot removes the conversion step from the conversation. Each member runs /tz once. After that, any time written into the chat can be expanded into a card showing that same moment in every zone the group actually contains, plus UTC, in one message everyone reads the same way.

Where the zones come from

The zone list is not configured, it is discovered. Whoever has run /tz in that chat contributes their zone, duplicates are collapsed, and the card shows the distinct set, up to twelve, with UTC alongside. A group of nine people spread over four countries produces a four-line card, not a nine-line one.

Daylight saving is computed at the moment you ask, through the platform's own timezone database, not stored as a fixed offset. That matters twice a year, when a hardcoded offset quietly becomes wrong for half the participants and nobody notices until somebody misses a call.

Zones can be given as IANA names (Europe/Warsaw, America/New_York), as the common abbreviations (UTC, GMT, CET, CEST, EST, EDT, PST, PDT, IST, JST, AEST), or as a plain offset like +2 or -5:30.

Inline mode works in any chat, including ones the bot has never been added to: type the bot's username followed by a time and it posts a one-off conversion card there.

Getting a group onto it

1. Add the bot. No admin rights required. It only answers its own commands.
2. Everyone runs /tz once. /tz Europe/Warsaw, or /tz CET, or /tz +2. This is per person and carries across every group the bot is in.
3. Ask a question. /when 3pm tomorrow returns the card. /now does the same for the current moment.
4. Save the zones you keep reusing. /preset add Asia/Tokyo keeps a zone under your account. Free holds three.
5. Or use it without adding it. Type the bot's username and a time in any chat for a one-off conversion, with no membership and no setup.

Command reference

Free and Pro

Pro is per person, one-time 150 Stars. Free presets are saved but not pulled into inline results; that connection is the Pro part.

What it stores

• Your saved zone and preset zones, under your user id.
• Named /team sets, stored against the group, for Pro groups.
• No message content. Nothing is stored except the zone names or offsets you explicitly save, and the DST offsets are computed live rather than kept.

Questions

How many zones fit on one card?

Every distinct zone set by members of that chat, deduplicated, capped at twelve, plus UTC.

What does it do in a private chat?

It shows your own zone only. The multi-zone card needs a group, because the group is where the other zones come from.

Is daylight saving handled?

Yes, and live. Offsets are resolved at the time of the query rather than stored, so a card is correct on both sides of a clock change.

Can I use it in a chat where the bot is not a member?

Yes. Inline mode posts a one-off card into any chat. A guest has no saved zone, so it reads as UTC plus a small default set.

What is /team for?

A recurring set of zones that is not the same as the group's membership: a client's hours, or three offices you always schedule against.

Other Telegram bots in this set

• Telegram Countdown Bot One pinned-worthy message, edited in place, never a second notification.
• Telegram Secret Santa Bot The group sees the Join button. Nobody sees the pairings.
• Telegram Birthday Bot Self-service dates, an automatic greeting, and a list of what is coming.

All of them are listed alongside the rest of Zovo's free online tools, and the browser-side half of the catalogue is under Chrome extensions.

Want the step-by-step walkthrough? Read Time zones across a distributed team: the full guide on tg.zovo.one.