What is TimeDifference.co?
TimeDifference.co is a suite of fourteen focused tools for working with time and dates: comparing time zones, calculating the difference between two dates, building shareable countdowns, tracking work hours, looking up Unix timestamps, finding meeting overlaps across continents, and more. Every tool is free, requires no sign-up, and runs entirely in your browser.
We built this site because the existing time-tool sites on the web were cluttered, slow, and over-engineered. We wanted something we'd actually want to use ourselves — clean, fast, and accurate, with thoughtful UX touches like shareable links, keyboard shortcuts, and a respectful dark mode.
What makes it different
Privacy first
Nothing is sent to a server. Calculations run entirely in your browser. Saved data (countdowns, recents) stays on your device.
Fast and lightweight
Pre-rendered static pages, no heavy frameworks or trackers. Loads in well under a second on Cloudflare's global network.
Accurate by design
Every tool uses the IANA timezone database via your browser's standard APIs — the same source operating systems rely on.
Free, forever
No paywalls, no premium tier, no email capture. Supported entirely by unobtrusive advertising so the tools can stay free.
Who is it for?
Anyone working across time zones: distributed and remote teams, freelancers with international clients, travellers, students, developers debugging timestamps, project managers tracking deadlines, parents counting down to school holidays, and people who simply need to know what time it is in another city.
Some tools — like the Unix Timestamp Converter and DST Checker — are oriented toward developers and operators. Others — like the Age Calculator and Countdown Timer — are useful for everyday personal use. The full set of tools is listed on the home page.
How it's built
The site is built as a single-page React application with TypeScript, pre-rendered to static HTML for every route. This means each page loads instantly from a CDN, and search engines can index the content without running JavaScript. It is hosted on Cloudflare Pages, which provides fast delivery to every region of the world.
Date and time calculations use modern browser APIs: Intl.DateTimeFormat for timezone formatting, Intl.supportedValuesOf for the complete IANA timezone list, and the standard Date object for arithmetic. No external time service is queried — your device's clock is the source of truth.
Frequently asked questions
Are the tools free to use?
Yes — every tool on TimeDifference.co is free, runs in your browser, and works without an account. There is no sign-up.
How accurate are the calculations?
All tools use the browser's built-in date and timezone APIs, backed by the IANA timezone database — the same standard used by operating systems. Results are accurate to the second.
Is my data private?
Yes. No calculations leave your device. Anything you save (recent tools, countdown events, work-hours entries) is stored in your browser's local storage and never sent to a server.
Can I share my work or settings with others?
For tools where it makes sense (Time Zone Converter, Meeting Planner, Countdown Timer), the configuration is encoded in the URL. Just copy the link and send it.
Do the tools work offline?
Once a page is loaded, most tools continue to work offline since they rely on the device clock and browser APIs.
Have feedback or a feature request?
We'd love to hear what tools are missing, what could work better, or just to say hello.
Get in touch