Features: time zones in Gmail and Chrome

Timehint is a time zone Chrome extension for Gmail. Its features fall into two groups: the ones that work on the email you read and write, and the ones that live in the browser side panel beside it. This page is a tour of all of them, with a link to the page that explains each in full. Everything described here is in Timehint 5.0, the version we're preparing for release, and everything is free during early access.

Time zone features in Gmail

Timehint runs on Gmail on the web, in Chrome and Brave on desktop. It changes three moments: opening a message, saving a new sender, and writing a time into a draft.

The sender's local time

Open a message from someone you've saved with a time zone and a chip appears on the message's recipient line: 4:35 PM there · Sent at 5:30 PM. The first value is their clock right now, the second is their clock when they wrote. Hover for their city, how far ahead or behind you they are, and both moments in your own time. If their clock matches yours, the chip reads Same timezone as you instead of repeating your time back at you.

Add timezone

Senders you haven't saved get an Add timezone chip with Add and Dismiss. Add opens a dialog with the sender's name, their address and a time zone field. When the message holds a usable clue (a location line in the signature, a phone number's country code, or a single time zone the sender wrote), the field is filled in for you, with the exact text the suggestion came from. You confirm or change it, and nothing is saved until you do.

Use their time, while you write

Type a time with a zone in a draft to a saved contact, such as "Can we meet at 5pm IST tomorrow?", and a chip offers their time: 5pm IST is 8:30pm JST for Kenji. Click Use their time and the draft changes; ignore it and nothing does. When the conversion lands on another date, the chip says "next day" or "previous day". In messages you receive, a time written with a zone gets your local time beside it.

Time zone features in the side panel

The side panel opens from the Timehint toolbar icon and sits beside whatever tab you're on, Gmail or not.

Your cast, with live local times

Your own clock is at the top. Below it are the people and places you've saved (your cast), each with their local time, how far ahead or behind they are (including half-hour zones, such as "9½ h ahead"), and a plain time-of-day label: Early morning, Morning, Afternoon, Evening or Late night. People are listed before places. You can pin a row to the top, hide rows you rarely need, and sort by name or by time.

The timeline and overlap windows

Today in your cast draws a 24-hour band for you and for everyone you've saved, split into work, fringe and off hours on their own clock. Overlap windows lists up to three stretches of the day when at least two of you are inside working hours, and marks the best one. You can look at any day from today to two weeks ahead, which is how you check the week of a clock change before it arrives.

How Timehint reads times and time zones

Under all of the above is one parser. It recognizes times the way people write them ("5pm IST", "17:00 CET", "1700 hrs IST", "noon in Singapore", "3pm Pacific Time", "5pm in Mumbai", "UTC+5:30") and resolves each to a real time zone before converting anything. Offsets come from that zone on the date in question, so daylight saving time is handled without a setting. Abbreviations that name more than one place have stated defaults, and a time written with no zone at all is left exactly as it is.

Where Timehint works, and where it doesn't

Being clear about the edges is part of the product:

Gmail on the web only. The chips, the Add timezone prompt and Use their time appear in Gmail in Chrome or Brave on desktop, version 114 or later. The side panel opens next to any tab, but Timehint doesn't add anything to other websites.
No phones or tablets. There is no mobile version, and the browser extension doesn't run in the Gmail mobile app.
It doesn't send or schedule email. Timehint shows times and offers conversions; your email client still does the sending.
One working-hours setting. Your working day applies to everyone in your cast. Timehint doesn't keep separate hours per person.
Contacts export, but don't import. You can download your contacts as a file from Settings; this version can't read one back in. To move them to another browser, sign in to the optional free account there and they sync.

Frequently asked questions

No. Every feature works without an account. Your saved contacts live in the browser profile you installed Timehint in, and you can download a copy from Settings at any time. A free account is optional: sign in to back up your contacts and keep them in sync across your browsers.

The sender chip and Use their time both need a contact saved with a time zone; neither guesses. The Add timezone prompt, converted times in messages you receive, the side panel and the timeline work without a saved contact, though the panel is empty until you add someone.

Yes. Every feature is free during early access, and there are no paid plans.

It isn't on the Chrome Web Store yet. Join the waitlist and we'll email you when it can be installed; an early-access link may reach you before the public launch.

For step-by-step instructions on each screen, read the full guide to using Timehint, or see why Timehint exists.

Timehint features: a time zone Chrome extension for Gmail