Online Stopwatch
Measure elapsed time, record split laps, and export timing records directly in your web browser.
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Free Online Stopwatch with Lap & Split Times
AlarmOnline.net provides a free online stopwatch designed for measuring elapsed time directly in your browser. Whether you are timing running laps, tracking workout intervals, rehearsing a presentation, or timing study sessions, you can start, pause, resume, capture split laps, and copy your lap history with a single click.
How to Use This Tool
- 1Start timing — Click the green "Start" button to begin measuring elapsed time.
- 2Record lap and split times — While the stopwatch is running, click the "Lap" button to log individual split intervals without stopping the overall timer.
- 3Pause and resume — Click "Pause" to temporarily freeze the elapsed time, then click "Resume" to continue timing whenever you are ready.
- 4Review lap performance — View recorded laps in the breakdown table, where your fastest and slowest laps are highlighted automatically.
- 5Copy or reset results — Click "Copy" to save your formatted lap table to your clipboard, or click "Reset" to clear all data and start fresh.
Key Features & Capabilities
Elapsed Time Measurement
Tracks elapsed hours, minutes, seconds, and hundredths of a second in real time.
Split & Lap Time Logging
Record multiple lap splits on the fly while the primary timer continues uninterrupted.
Automatic Lap Highlighting
Instantly flags your fastest lap in green and slowest lap in red for quick performance analysis.
One-Click Data Export
Copy your complete lap breakdown with individual durations and cumulative totals to your clipboard for spreadsheets or notes.
Pause, Resume & Clear
Flexible controls to pause intervals, resume seamlessly, or clear all recorded times with one click.
Integrated Time Tools
Need countdown or scheduled alarms? Use our Online Timer for interval countdowns, create a date-based Event Countdown, set clock-time alarms with our Online Alarm Clock, or check the full-screen Online Clock.
Popular Use Cases
Running & Track Splits
Measure 400m intervals, sprint times, track laps, and pacing during running sessions.
Workouts & Fitness Training
Time HIIT intervals, circuit training stations, plank holds, and rest intervals.
Study & Productivity Sprints
Track how long tasks, reading sessions, coding sprints, or problem-solving exercises take.
Presentations & Speeches
Rehearse speech pacing, slide transitions, and meeting presentation lengths.
Cooking & Process Timing
Time precise culinary steps like brewing coffee, searing steaks, or dough kneading.
Games & Competitions
Measure puzzle solving times, board game turns, speedcubing, and friendly challenges.
Frequently Asked Questions (FAQ)
How do I use the online stopwatch?
Click the green "Start" button to begin measuring elapsed time. While timing, click "Lap" to record individual split times. Click "Pause" to temporarily stop the clock, "Resume" to continue, or "Reset" to return to zero.
Is this online stopwatch free?
Yes. The online stopwatch on AlarmOnline.net is completely free to use with no fees, subscriptions, or account registration required.
Do I need to install anything?
No software installation or browser extension is needed. The stopwatch runs directly in any modern desktop, tablet, or mobile web browser.
Can I record lap or split times?
Yes. Whenever the stopwatch is running, click the "Lap" button to capture individual split times. The tool automatically displays the lap number, individual lap duration, and cumulative overall time.
Can I copy or export my lap times?
Yes. Click the "Copy" button in the lap history header to copy your formatted lap results table directly to your clipboard to paste into spreadsheets, documents, or notes.
Can I pause and resume the stopwatch?
Yes. Click "Pause" to freeze the elapsed time at any point. When you are ready to continue, click "Resume" to pick up exactly where you left off.
Will the stopwatch keep running if I switch browser tabs?
Yes. The stopwatch calculates elapsed time by comparing high-resolution system timestamps, ensuring your timing remains accurate when switching between browser tabs or minimizing the window.
Will it keep running if I close the browser?
No. Browser-based tools require the active browser tab or window to remain open. If you close the tab or quit the browser, the current stopwatch session will end.
How precise is the online stopwatch?
The stopwatch displays elapsed time with hundredths-of-a-second (0.01s) resolution. Internal elapsed calculations use the browser high-resolution timestamp API (performance.now()), though real-world manual timing is naturally subject to human click reaction time and display refresh cycles.