How to use the online timer
Second-based timers suit anything short enough that a minute would be too coarse a unit — brief, intense workout intervals, a quick breathing exercise, or the seconds-long stages inside a longer routine like the rest between exercises in a circuit. When the difference between fifteen and twenty seconds actually changes the outcome, rounding up to the nearest minute defeats the purpose.
Precision matters more at this scale because these durations are frequently short by design — a Tabata round's twenty seconds of work, or the fifteen-second transition in a circuit, is meant to be tight, and stretching it even slightly changes the character of the exercise. A second-based timer keeps that tightness accurate rather than approximate.
Set the exact duration you need, whether that's a single short interval or a countdown to mark a brief pause, and let it run precisely rather than eyeballing a stopwatch or guessing at a rough feel for how long a handful of seconds actually takes.