How focus timer works
Run a local countdown with start, pause, and reset controls.
Formula and convention
Uses a fixed finish timestamp rather than subtracting one second per interval. Pause preserves the remaining duration.A worked example
A 25-minute session counts down to zero. Choose a shorter block whenever that is easier to protect.
Scope and precision
Runs while the page is open and resets on reload. Sleeping devices may delay display updates; no alarm permission is requested.
Displayed results may be rounded. Inputs are processed locally and are not stored by this site. Keep the original values if you need to reproduce the result.
Why might another tool give a different result?
Compare unit definitions, rounding, period assumptions, and input values. This page states the convention used by this calculator.