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.

Personal work stays in your browser

The personal task lists, focus history, habits and planners save your work in your browser. These tools do not upload that work to a server. There is no account or cross-device backup: clearing site data removes saved work, and another browser starts with its own separate storage. Export or copy anything you need to keep. The privacy policy explains which tools save data and what leaves your device.

Shared rooms send data to a server

Planning poker, retros, meeting polls and the other live collaboration rooms send participants' names, identifiers and shared content to Cloudflare so the room can stay in sync. Anyone with its link can join. Rooms expire after inactivity, but they are not private storage or a substitute for a confidential team channel.

Pages that actually tell you something

The tool guides explain how to read results, work through examples and recognise limitations. The longer articles discuss the methods behind the tools and link to further reading so you can choose an approach that suits your work.

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 and circulates through interviews and secondary writing instead; the measured figure, about 10 to 15 minutes to get back to focused work, comes from a different paper altogether, Iqbal and Horvitz (2007). 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. Personal saved work goes to localStorage; shared rooms use Cloudflare Durable Objects. Advertising is not currently enabled, and there is no Google Analytics, tag manager or tracking pixel. Cloudflare Web Analytics is on: the host adds a cookieless beacon that reports page views and page-speed measurements, with no fingerprinting and no tracking across sites, and only aggregate figures come back. The privacy policy covers it, and any future advertising setup will be described there before it is enabled.

The expanded city directory uses location data from GeoNames, retrieved through the Open-Meteo geocoding service on 6 September 2026, under the Creative Commons Attribution 4.0 licence. We select the locations, adapt some display names and assign stable identifiers. Coordinates represent city centres; population figures help order search results and are approximate. Searches use the directory bundled with the site.