About ChronoClock

ChronoClock is a collection of small, focused tools for working with time: a world clock and time zone converter, a Pomodoro timer and a set of other timers, a task manager, a GTD workflow, daily and weekly planners, a habit tracker, calculators, printable templates, long-form guides, and real-time rooms for team rituals like planning poker, retros and meeting polls.

All of it is free and open in the browser. There is nothing to install, no account to create, and no trial that ends. Open a page, use the tool, close the tab.

Your data is yours, physically

Most productivity apps want an account so your data lives on their servers. This one takes the opposite approach: your tasks, sessions, habits, plans and settings are written to your own browser and never sent anywhere. That means no sign-up, no password, no export request, and nothing for anyone to lose in a breach. The trade-off is real and stated plainly in the privacy policy: nothing syncs between devices, and clearing your browser data deletes it for good.

Pages that actually tell you something

Every tool page carries real instructions for using the method it implements, not a paragraph of filler under the widget. If a page explains a technique, it explains where the technique came from and what it is good for.

A lot of productivity writing repeats claims that did not survive checking. The guides here say so instead, even when the honest version is less satisfying.

Ego depletion, the idea that willpower is a fuel tank that drains as you use it, failed two large multi-lab replications with over 5,600 participants combined. The widely quoted claim that it takes 23 minutes and 15 seconds to refocus after an interruption appears in none of Gloria Mark's published papers; her studies found 11 to 16 minutes, and the number came from a press interview. The 25-minute Pomodoro has no scientific derivation at all: Francesco Cirillo tried intervals between roughly 5 and 30 minutes as a student and kept 25 because it suited him and his kitchen timer.

The time guide goes through the evidence in more detail, including the techniques that do hold up.

The individual tools work on their own, but they are built to chain into one loop:

1. Capture everything on your mind in the GTD inbox so you are not holding it in your head, then triage it into next actions.
2. Estimate each task in focus sessions on the task list, which forces a size rather than a vague intention.
3. Run the block with the Pomodoro timer or a Flowtime session if a fixed interval gets in the way.
4. Review what actually happened in focus stats, then use those real numbers for the next round of estimates.

The planners, habit tracker and calculators hang off the same loop, and the team rooms cover the parts of the week that involve other people.

ChronoClock is a Next.js app running on Cloudflare Workers. Time zone handling uses the IANA database already present in your browser rather than a bundled copy, so the rules stay current with your system. Sunrise, sunset and moon phases are computed locally in the browser. Saved work goes to localStorage. There is no analytics script, no tag manager and no tracking pixel anywhere on the site.

Bug reports, corrections to a guide and requests for a tool that is missing are all welcome at hello@chronoclock.app. If you found an error in a research claim, a source link is the most useful thing you can send.