Développeurs

Time Zone Converter

Compare up to four time zones side-by-side with a live 24-hour grid. Search by city, country, IANA ID, or abbreviation (GMT, NPT, IST, EST…), star favorites, and pick a meeting time that works everywhere.

Résumé de l'outil

Cet outil accepte une entrée structurée et renvoie une sortie déterministe dans le navigateur, sans envoi au serveur.

Nom de l'outil: Time Zone Converter
Intention d'entrée: Fournissez le contenu source à transformer, valider ou analyser.
Intention de sortie: Recevez une sortie normalisée prête à être copiée, réutilisée ou déboguée.
Entrée d'exemple: GMT ↔ NPT
Sortie d'exemple: GMT 09:00 → NPT 14:45 (same day)

Introduction à l'outil

Vue d'ensemble de l'outil

The time zone converter helps you plan calls, releases, and travel across regions without doing the math in your head. Type Kathmandu, Nepal, NPT, or Asia/Kathmandu — they all resolve to the same zone. Add up to four cities and the tool draws a 24-hour strip for each one, anchored to the reference zone's local day. Click any hour cell to mark a meeting time and instantly see what it lands on in every other zone (and whether it crosses a day boundary). Everything is computed in your browser using the IANA database via the standard Intl APIs, so daylight-saving transitions are handled correctly and no data leaves your device. Favorite cities, your home zone, your last comparison, and your 12h/24h preference are saved in your browser on this device. You can also save named comparisons — keep one set for NPT–EST–EAT and another for a different team — and share any comparison with a link. Sign in and your saved comparisons sync across devices and show up on your account page.

Cas d'usage

Schedule a meeting between teammates in Kathmandu (NPT) and London (GMT/BST).
Coordinate a release window across IST and EST without arithmetic.
Plan a call that respects working hours in three or four offices at once.
Quickly check what time it is in any major city before sending a message.

Exemples d'entrée/sortie

Nepal is UTC+5:45, an unusual 45-minute offset.

Intention d'entrée

GMT ↔ NPT

Intention de sortie

GMT 09:00 → NPT 14:45 (same day)

India is UTC+5:30; New York is UTC−5 (or UTC−4 during DST).

Intention d'entrée

IST ↔ EST

Intention de sortie

IST 21:00 → EST 10:30 (same day)

Many Sydney mornings are still the previous calendar day in New York.

Intention d'entrée

Sydney ↔ New York

Intention de sortie

Sydney Mon 09:00 → New York Sun 17:00

Questions fréquentes

Does it handle daylight saving time?+

Yes. Offsets and abbreviations come from the IANA tz database via the browser's Intl API, which knows DST rules and historical changes for every supported zone.

Why does an hour sometimes show '+1d' or '−1d'?+

When a zone is far enough ahead or behind the reference zone, the same instant falls on the next or previous calendar day. The day badge tells you so you do not book Monday in one city and accidentally land on Tuesday in another.

Where are my saved comparisons and favorites stored?+

On this device, in your browser's local storage — nothing leaves your device by default. If you sign in, your saved comparisons also sync to your account so you see the same ones on every device, and they appear on your account page.

Can I compare more than four zones?+

Four is the cap to keep rows readable on phones and laptops. Remove a zone first if you want to swap one in.

What does the 'reference' label mean?+

The top zone defines which local day the 24-hour grid is anchored to. Reorder rows with the up/down arrows to make a different zone the reference.