Online Stopwatch
Millisecond precision · Lap recording
Quick guide
What can Stopwatch / Timer help you do?
Free online stopwatch. Millisecond precision, lap recording, CSV export. Perfect for sports, study, cooking.
Best for
Use this to measure an activity duration and compare successive segments, such as rehearsals, demonstrations or repeated steps. It supports pausing, resuming and exporting laps, but does not provide cloud records or a calibrated timing system for official competition results.
How to use it
Start the timer and record laps as needed, pausing and resuming between active periods. Export downloads a CSV only when laps exist. Reset clears both time and laps; Clear Laps keeps the total timer but makes the next split start from the overall timing origin.
How to read the result
The main display shows hours, minutes, seconds and three millisecond digits. Each lap includes its split since the previous recorded lap and the cumulative total, excluding pauses. Newest laps appear first onscreen; the CSV reverses them into chronological order with Lap, Split and Total columns.
Privacy and limits
The widget uses browser high-resolution timing and keeps lap records in page memory, without uploading them or automatically saving them. CSV export creates a local download containing lap numbers and durations. Sharing that file exposes those records to its recipients, even though it contains no activity name.
Millisecond digits describe formatting, not guaranteed millisecond accuracy for manual actions. Screen updates depend on refresh and tab state, and device sleep behavior can affect long measurements. Export needed laps before leaving or refreshing; this widget does not promise to restore a previous timing session.
Frequently Asked Questions
Can I record laps?
Yes, click Lap during a run to mark a split. Export as CSV for analysis.
Will it persist after close?
No, history is not stored. Use Export CSV to save.
How precise?
Uses performance.now(), millisecond precision.