Elapsed Time Calculator
How long since — counting up, live
Pick a moment and watch the time since it climb, second by second. The page keeps ticking, so it works as a running clock on anything you have started.
Questions people ask
The things that come up about elapsed time calculators, answered plainly.
Does it keep counting if I leave the tab?
Yes. The elapsed time is computed from the clock each tick rather than accumulated, so a backgrounded or throttled tab catches up correctly the moment you return.
How is this different from a stopwatch?
A stopwatch starts when you press it. This measures from a moment you name, which can be in the past — when a service last deployed, when a record was set, when you last had a cigarette.
Related tools
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Countdown TimerSet a duration or a target time and let it run, with a sound and a title flash when it finishes. Nothing is installed and nothing is uploaded — the timer is the page.
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Time Difference CalculatorTwo clock times or two full timestamps, and the difference in hours, minutes and seconds — including the overnight case, where the end time is smaller than the start.