Laps and splits on a stopwatch, and how precise it is.
What the lap and split buttons record, how to read fastest and slowest laps, and why your reaction time matters more than hundredths.
By Suraj Kumar3 min read
A stopwatch has one more button than people use: the lap. Here is what it records.
Lap and total.
Press Lap and the stopwatch keeps running while it notes the time. The lap time is the time since the last press; the total, often called the split, is the time since the start. The stopwatch shows both, and marks the fastest and slowest lap.
Hundredths, and your thumb.
The stopwatch shows hundredths of a second, worked out from the moments you pressed. A person takes about a fifth of a second to react, so hand timing is far less precise than the digits; use them to compare laps timed the same way.
Keys and copying.
Space starts and stops it and L takes a lap, so you can time without the mouse. Copy puts the laps in a table you can paste into a spreadsheet.
Further reading
Topics: stopwatch · stopwatch with laps · lap vs split · online stopwatch · lap timer · split time
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