About TimeZoneSimple

TimeZoneSimple started as a small side project: a one-page timezone converter with no sign-up, no clutter, and no dark patterns. That's still the core of the site — but a bare converter with nothing around it isn't much use to anyone who wants to actually understand timezones, not just plug numbers into a form. So alongside the tool, the site now includes plain-English guides on daylight saving time, UTC, and how to actually pick a meeting time that doesn't wreck someone's morning.

How the conversions work

Every conversion runs on the IANA Time Zone Database (also called tz database or zoneinfo) — the same dataset browsers, phones, and most server software use internally. Rather than storing a fixed UTC offset per city, it stores the actual historical and future daylight saving rules for each region, so a conversion for a date next December is calculated using the correct rules for that specific date, not just "add 5 hours" regardless of season. That matters more than people expect: two cities can be 8 hours apart in July and 9 hours apart in January purely because one observes daylight saving and the other doesn't.

What the site doesn't do

• No account or login is required to use the converter.
• No location data is sent anywhere — timezone detection happens entirely in your browser using the standard Intl API, and nothing is logged server-side.
• No push notifications, no email capture, no "download our app" interstitials.

Who it's for

Remote teams scheduling across regions, people coordinating travel plans, anyone with family or friends abroad, and anyone who's ever typed "what time is it in Tokyo right now" into a search bar and wanted a faster answer than scrolling through ads to find it.

Questions, corrections, or a city missing from the list? Get in touch.