Updated: August 2026 • Verified v1.2
Online Stopwatch & Countdown Timer
Fun & DecisionPopularHigh-precision millisecond stopwatch with lap recording and customizable countdown alarm with Web Audio beeper alerts.
Local Browser Execution: Your input is processed locally in your browser and is not sent to UTL servers.
t_elapsed = Date.now() - t_startWas this calculation helpful?
Understanding Your Results
Provides large high-contrast digits with milliseconds display, lap history records, and audio buzzer alarm upon completion.
Practical Guidance & Next Steps
Use quick preset buttons (5 min, 15 min, 25 min Pomodoro) to launch countdowns with 1 click.
What is this?
A high-precision millisecond stopwatch and countdown alarm timer with customizable lap recording.
How does it work?
1. Click Start to track elapsed time with millisecond precision.
2. Record lap splits with 1 click.
3. Switch to Countdown mode for Pomodoro and work sprints with audio alerts.
Why use it?
Clean, distraction-free timing without popup ads or battery-draining apps.
Technical Scope & Calculation Limitations
Timers run while the browser tab is open. If your computer goes to sleep, the timer will pause until wake.
Frequently Asked Questions
Yes, it generates a clear synthesized audio beep using the Web Audio API.
Windows Desktop & Widget Options
All Windows widgets Want this capability on your Windows desktop?
Windows 11 Widget
9.5/10
Windows Clock & Focus Sessions
Built-in Windows 11 Focus timer and clock widget with Spotify audio and Microsoft To-Do sync.
FreeEasy InstallLow RAM
By Microsoft CorporationView Widget
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