Online Stopwatch - Millisecond Precision
Time events with absolute precision. Our free online Stopwatch provides millisecond accuracy and lap tracking, running entirely offline in your local browser.
What is the Online Stopwatch?
Whether you are timing a sprint, measuring how long a specific script takes to execute, or managing a presentation, you need an accurate stopwatch. The built-in timers on mobile phones are great, but sometimes you need a large, visible digital display on your desktop monitor. This web-based Stopwatch utilizes your browser's high-resolution `performance.now()` API to guarantee millisecond precision. Because it relies entirely on client-side processing, there is zero network latency to skew your timing, and it works perfectly even if you lose your internet connection.
Why Use Our Stopwatch?
- Millisecond Precision: Uses advanced browser APIs for highly accurate timing.
- Lap Tracking: Easily record splits without stopping the main timer.
- Large Display: Perfect for projecting on a screen or viewing across a room.
- Offline Capable: Does not require an internet connection once loaded.
How to Use the Stopwatch
Click the large 'Start' button to begin timing.
Click 'Lap' to record a specific split time in the log below.
Click 'Stop' when the event concludes.
Click 'Reset' to clear the timer and lap history.
Frequently Asked Questions
Yes, if the operating system suspends the browser processes to save power, the timer will pause or lose accuracy. Keep the screen active for long timings.
No, all timing data is strictly temporary and exists only in your local browser memory.
Yes, the tool is optimized for keyboard accessibility for faster reaction times.
All file processing is performed locally in your web browser. We do not upload, store, or view your data.