Dual Stopwatch

The “Start both” button and the spacebar start both stopwatches at once: one timestamp is taken and given to both, so the difference between them starts from zero. The same button stops both.

Below the displays there is a difference line, and it appears once both counts are running. It shows the absolute value, so it does not matter which of the two is ahead. Stop one, and the difference freezes and shows the gap at that moment.

Separate laps for each

Start, Lap and Reset are separate for the first and the second stopwatch, and laps go into their own table. The best and the worst lap are marked, as in the regular stopwatch.

The screen stays on, a reload does not break anything

While at least one count is running, the page keeps the screen awake. Both times and all laps are stored in the browser: if you refresh the tab or the browser drops it from memory, the counts continue from the same point, and a running stopwatch gains whatever time passed by the device clock.

Keyboard keys

• Space: start or stop both
• 1: first stopwatch
• 2: second stopwatch
• R: reset both

Where it comes in handy

Two runners or two teams on the same course, two games of a board game running side by side, boiling and frying on neighboring burners, a talk and the questions after it. The page counts the gap between the two times, not just each of them.