Runs fully in your browser. Inputs stay on your device. See recent fixes on changelog.
Online Stopwatch
Precise stopwatch with lap times and split tracking.
FreeRuns in browseronline stopwatchstopwatch
Cmd/Ctrl+Enter Primary actionCmd/Ctrl+Shift+L Load sampleCmd/Ctrl+Shift+X Clear/resetCmd/Ctrl+Shift+C Copy result
About Online Stopwatch
Precise stopwatch with lap times and split tracking. Use a precise online stopwatch for free. Features lap time recording, split tracking, and millisecond accuracy for timing workouts, tasks, and experiments. Produces high-quality output using configurable parameters and the browser's native random number APIs. Includes options for customizing format, length, and character sets. Everything runs client-side in your browser for maximum speed and privacy — no data is sent to any server, and no signup is required.
Related tools: Online Timer, Pomodoro Timer, Time Addition Calculator
How to Use Online Stopwatch
- Configure the options and parameters as needed.
- Click Generate to produce the output.
- Copy or download the generated result.
Frequently Asked Questions
What is Online Stopwatch?
Use a precise online stopwatch for free. Features lap time recording, split tracking, and millisecond accuracy for timing workouts, tasks, and experiments.
Are generated values truly random?
The tool uses the browser's built-in cryptographic random number generator (crypto.getRandomValues) when security matters, and high-quality pseudo-random algorithms for general-purpose generation. This ensures unpredictable, non-repeating output.
Can I customize the output?
Yes, the generator provides controls such as sliders, toggles, and selection menus to fine-tune the output to your exact requirements. Adjust length, character sets, formats, and other parameters before generating.
How are random values generated?
Values are generated entirely in your browser using JavaScript's native APIs. No external service or server call is involved, which means generation is instant and your output is never transmitted anywhere.
Is Online Stopwatch free to use?
Yes, this generator is free to use with no limits on how many values you can create. No signup or account is needed.
Is my data safe when using Online Stopwatch?
Yes, all generation happens in your browser. Nothing is sent to a server, and no generated values are stored or tracked.