Online Stopwatch

What the online stopwatch does

This is a plain stopwatch that counts up from zero. Press start and it begins ticking, showing minutes, seconds, and hundredths of a second, with stop and reset whenever you need them. It answers the question "how long did that take," which is the opposite of a countdown. No setup, no duration to enter, just start it when something begins and stop it when it ends.

How to use it

1. Start. Begins counting up from where the display sits.
2. Stop. Freezes the time so you can read it.
3. Reset. Clears the display back to zero.

Pressing Start again after a Stop picks up from the frozen time rather than starting over, so you can time something in stages.

How it works

When you press start, it notes the moment and then updates the display very frequently, about a hundred times a second, working out how much time has passed and showing it as minutes, seconds, and hundredths. Stop simply pauses that updating and leaves the number on screen. Because Start continues from where you stopped, you can pause and resume to add up several stretches, while Reset wipes it clean for a fresh run.

Stopwatch or timer

The two get mixed up, so here is the simple split. A stopwatch counts up from zero and tells you how long something took, when you do not know the length in advance. A countdown timer starts from a set duration and counts down to zero, telling you when a known length of time is up. If you are measuring how long a task runs, use the stopwatch. If you want to be alerted after a fixed amount of time, use a timer. This page is the count-up one.

What the hundredths are good for

The display goes down to hundredths of a second, which is finer than most everyday timing needs but nice to have. It is plenty for timing a practice run, a lap, a task, or a quick benchmark where you want a bit more than whole seconds. Worth being realistic, though: a stopwatch in a browser is at the mercy of how busy your device is, so for casual timing the hundredths are spot on, but it is not a lab instrument measuring to the millisecond. For anything where a hundredth of a second genuinely decides the outcome, dedicated timing equipment is the right call.

Where it fits

Timing things where you do not know how long they will take. How long a chore actually takes, a rehearsal or a speech run-through, a workout set, how long something needs on the stove, or a simple speed test of one approach against another. The pause-and-resume makes it handy for adding up time across stop-start activities, like totalling the time you actually spent on a task through the day.

Questions people ask

How is this different from a countdown timer?

A stopwatch counts up from zero to measure how long something takes. A timer counts down from a set duration to tell you when time is up. This one counts up.

Does Start continue after I Stop, or start over?

It continues from where you stopped, so you can pause and resume to time something in stages. Use Reset when you want to start from zero.

How precise is it?

It shows hundredths of a second, which is fine for everyday timing. Browser timing depends on how busy your device is, so it is not lab-grade to the millisecond, but it is plenty for practice runs and quick benchmarks.

Does it show hours?

It counts in minutes, seconds, and hundredths, so the minutes simply keep climbing past 60 for longer sessions rather than rolling over into an hours field.