About Just a Timer

Just a Timer is run by a single independent builder as five free timers -- an online timer, a countdown to any date, a stopwatch, a Pomodoro timer and an interval timer -- built around one idea: a countdown that stays exact no matter what the browser is doing around it. Every timer states how it keeps time, works entirely on your device, and never sends anything you type anywhere.

How the timers stay accurate

Every countdown on this site -- the Online Timer, the Countdown Timer, the Pomodoro Timer and the Interval Timer -- works the same way underneath: instead of counting down one second at a time, it records the exact timestamp the countdown should reach zero and recomputes the time remaining from that fixed target on every screen update. A browser tab that's backgrounded, minimized, or throttled to save battery doesn't cost any accuracy, because there's no running tick count to fall behind on. The Stopwatch uses the mirror image of the same idea: elapsed time is the current time minus the moment it was started, not an accumulating counter. Every timing function is checked against a hand-derived expected value in the site's own test suite before it ships.

What runs where

Every calculation, every countdown, and the alarm sound itself (synthesized live with the Web Audio API, not an audio file) run entirely in your browser. The site remembers your last-used duration, your mute preference and your alarm tone in your browser's local storage so they carry over next time -- nothing is sent to a server, and there are no accounts. If you turn on the optional "browser notification" setting on the Online Timer, your browser will ask for permission once; nothing is requested until you opt in.

What it doesn't do

These timers aren't a substitute for a certified stopwatch or a safety-critical timing device, and Just a Timer isn't affiliated with any fitness brand, productivity method, or organization named on this site. See Terms.

Every timer

• Online Timer -- Set a countdown in hours, minutes and seconds and start it instantly: a huge display, an audible alarm, an optional browser notification, and a duration that stays exact even in a background tab.
• Countdown Timer -- Count down to any date and time -- a deadline, a launch, an event -- shown in days, hours, minutes and seconds, with a shareable link and the same alarm as the main timer.
• Stopwatch -- Start, stop, lap and reset a precise stopwatch that keeps counting accurately even if the tab is backgrounded, with a lap table showing split and total time and one-tap copy.
• Pomodoro Timer -- The classic 25-minute focus session with a 5-minute break and a longer break every 4 sessions -- every interval is editable, with auto-advance and a session counter.
• Interval Timer -- Set a work time, a rest time and a number of rounds -- with HIIT and Tabata presets -- and get an audible cue at every transition, hands-free.

Corrections

If something on this site is wrong or out of date, email hello@justatimer.com.