Set the timer to 170 seconds

How to use the online timer

Rest periods matter as much as the work itself, and 170 seconds is a common gap between rounds in a lot of interval training. Start it the moment you finish a set, use the time to catch your breath and grab some water, and get ready to go again as soon as it counts down to zero. Watching a clock never feels as precise as letting the timer call it.

There's no setup beyond pressing Start, and the countdown handles the rest on its own from that point. Since it runs inside the browser, keep the tab open for the timer to keep an accurate count; you can switch to other tabs in the meantime, but closing this one out resets things. When the countdown hits zero, a sound plays so you're not stuck staring at the numbers.

A phone timer works fine until a call comes in or a notification steals the screen at the worst moment. Running it in a browser tab keeps it separate from all that, ticking away quietly in the background of your computer or phone without competing for attention until it's done. There's nothing to install and nothing to sign up for, just a page that does one job well. Set a timer for 170 seconds, set the timer to 170 seconds, start a 170 seconds timer — it is the same countdown either way.