How to time laps accurately.
Start the session, tap Lap at the same physical timing point, then compare each completed lap with your best or previous result.
Record a complete session
- Choose the sport mode. Select Circuit, Karting, Cycling or Running. The mode labels the session; the core stopwatch works the same way.
- Press Start session. Start at the exact point from which you want the first lap measured.
- Press Lap at every crossing. Use the same visible timing point each time. The completed lap is added instantly to Recent Laps.
- Pause when timing is finished. Pausing stops the clock without deleting the recorded laps.
- Save to Lap History. A saved session remains on this device until you delete it or clear browser data.
What each timing metric means
Current lap
The time elapsed since the session started or the last Lap press.
Last lap
The duration of the most recently completed lap.
Best lap
The shortest completed lap in the active session.
Average
The arithmetic mean of all completed lap durations.
Total time
The accumulated running time for the current session.
Relative pace
A visual bar comparing each recent lap with the fastest and slowest laps in that session.
How lap delta works
Lap delta shows how much faster or slower a completed lap was than a baseline. In Settings, choose whether that baseline is the best earlier lap or the immediately previous lap.
- Negative or green: the lap was faster than the comparison lap.
- Positive or red: the lap took longer than the comparison lap.
- Best: the shortest completed lap in the session.
Example: a delta of +0.207 means the lap was 0.207 seconds slower than the selected baseline.
Tips for consistent manual timing
- Stand where the start/finish point is clearly visible and use that exact point for every tap.
- Keep the device awake and the timer page in the foreground during the session.
- Use a stable connection for the first load; the installed web app can reuse cached resources afterward.
- Avoid switching apps while timing, because mobile operating systems can restrict background updates.
- Use dedicated transponder equipment when certified motorsport timing or safety-critical accuracy is required.
Racing LapTimer is a manual browser stopwatch. It does not claim the precision of a circuit transponder or sanctioning-body timing system.
One timer, four practical uses
Circuit
Time cars or motorcycles from a fixed start/finish point during practice or track days.
Karting
Compare short, closely matched laps and spot consistency across a run.
Cycling
Measure repeated circuits, training loops or individual efforts.
Running
Record track laps or repeated loops without creating an account.
Frequently asked questions
Does Racing LapTimer use GPS?
No. The current version is a manual lap timer and does not collect GPS positions or display a track map.
Are my lap times uploaded?
No. Saved sessions are stored locally in the browser on your device. Sharing occurs only when you choose the Share action.
Can I use it on a phone and computer?
Yes. The interface is responsive and works in modern browsers on phones, tablets and desktop computers.
What happens when I press Reset?
If the session contains laps, Racing LapTimer asks whether to save them before resetting. This prevents accidental loss.
Is Racing LapTimer free?
Yes. The browser-based timer can be used without a paid account.