00:0000

Laps you record will show up here.

Online Chronometer

A clean online stopwatch — start, lap and reset, accurate to a hundredth of a second. It runs entirely in your browser: nothing to install, no account, and the timer keeps correct time even if you switch tabs.

A free online chronometer, ready when you open the page

This is a full-screen online chronometer built for one job: measuring how long something takes, precisely, without getting in the way. Press start and the digits move immediately. There is no sign-up, no download and no app to keep updated — the entire stopwatch is a single web page, so the same link works on a laptop, a phone or a tablet, and it keeps working offline once the page has loaded.

People reach for a stopwatch online for very different reasons: timing intervals at the track, holding a plank, portioning a study session, checking how long a build takes, running a lab experiment, or keeping a presentation inside its slot. The chronometer treats them all the same way — a large, readable clock, three controls, and a record of every split you mark.

How to use the stopwatch

  1. Press Start — or tap Space — to begin timing.
  2. Press Lap to record a split without stopping the clock. The list marks your fastest lap in green and your slowest in red, so the session reads at a glance.
  3. Press Stop to pause and Resume to continue from the same reading — pausing never loses the time already banked.
  4. Use Export to download your laps as CSV for Excel or Google Sheets, as TSV, or as JSON.
  5. Reset appears once the chronometer is stopped, and asks first so a full session is never lost by accident.

What this online timer gives you

  • Hundredth-of-a-second precision read from the browser's high-resolution clock.
  • A lap timer that records splits and marks the fastest and slowest of them.
  • Renameable rows — count laps, sets, reps, rounds or strokes, whatever you are actually measuring.
  • Keyboard shortcuts for start, stop, lap and reset, so a desk session never needs the mouse.
  • Export to CSV, TSV or JSON when the numbers need to leave the page.
  • Light and dark, with the type size, corner style and accent colour following the site's appearance settings.

Chronometer or stopwatch?

In everyday use the two words mean the same thing: a device that measures elapsed time from zero. Strictly, a chronometer is a timekeeping instrument certified for accuracy, while a stopwatch is a handheld timer you start and stop. Search for an online chronometer, a digital stopwatch or a lap timer and you are looking for this page either way.

Frequently asked questions

What is an online chronometer?
An online chronometer is a stopwatch that runs in your browser. You open the page and start timing — there is nothing to install, and it works the same on a phone, a tablet or a desktop.
How accurate is this stopwatch?
It reads the browser's high-resolution clock and displays hundredths of a second. Because every reading is derived from real timestamps rather than counted frames, the elapsed time stays correct even if the page is busy or the tab goes to the background.
How do I use the lap timer?
Press Lap while the chronometer is running to record a split. Every lap is listed with its own time, and the fastest and slowest laps of the session are highlighted so you can compare them at a glance.
Are there keyboard shortcuts?
Yes. Space starts and stops the online stopwatch, L records a lap, and R resets everything back to zero.
Does the chronometer keep running if I switch tabs?
Yes. The timer is based on the clock, not on the page being visible, so switching tabs or locking your phone does not lose time — the correct reading appears as soon as you come back.
Is it free?
Completely. The online chronometer is free to use, needs no account, and stores nothing about you.