Set the timer to 21 minutes

How to use the online timer

A sauce that needs to reduce properly wants 21 minutes of gentle simmering, not a rolling boil that scorches the pan while you're not looking. Set the timer once it's bubbling nicely, give it the odd stir, and use the last stretch to taste and adjust the seasoning rather than walking off. A timer tracking it frees you up to get the rest of dinner sorted at the same time.

Press Start and away it goes, counting down on its own without needing you to babysit it every few seconds. The only real rule is keeping this browser tab open, since the countdown pauses along with the page if you close it or shut the browser down entirely. Right at zero, a sound plays to let you know time's up, clear enough to hear from the next room over.

A kitchen timer only works in the kitchen, and a phone timer competes with texts, calls, and every other app fighting for your attention. Keeping the countdown in a browser tab sidesteps both problems: it goes wherever your laptop or phone goes, and it isn't trying to notify you about anything else. Minimise it, work on something else, and it'll be counting when you check back. Set a timer for 21 minutes, set the timer to 21 minutes, start a 21 minutes timer — it is the same countdown either way.