Boxing Timer Create a custom interval timer for HIIT on iPhone
When none of the built-in formats matches a 45/15 interval, Custom Timer covers it. Tap Setup > Custom Timer, set Rounds, Round (work), Rest and Prep, choose a Warning, then tap Use Once or Save & Use. 45 seconds of work and 15 of rest for 10 rounds comes to 9:55 with a 10-second prep.
When a custom interval timer makes sense
The ready presets cover the common formats fine, but circuits, conditioning finishers and whatever a coach wrote on the whiteboard today rarely line up exactly. A custom timer lets you type in the work and rest your plan actually asks for, and still get the bell, the warning and the Lock Screen countdown — same features, just your own numbers.
How to create a custom interval timer
- Tap the list icon at the top left to open Setup and scroll to Custom Timer, the last row.
- Under Name, type a name or keep My Timer.
- Set Rounds from 1 to 99. Set 0 for unlimited rounds that run until you tap Stop.
- Under Durations, set Round (your work time), Rest and Prep. They move in 5-second steps.
- Under Warning, choose how many seconds before the end of each round the clacker sounds (0 to 30, in 1-second steps; 0 turns it off).
- Tap Use Once to start with it without saving, or Save & Use to keep it under My Presets at the top of Setup.
- Close the sheet and tap Play.
Worked examples: 40/20, 45/15 and 3 minutes with 30 seconds rest
Total time is prep + rounds x work + (rounds - 1) x rest, because there is no rest after the last round. These are computed with the app's own rule.
| Timer | Rounds | Work / rest | Prep | Total |
|---|---|---|---|---|
| HIIT 40/20 (built-in) | 12 | 0:40 / 0:20 | 5 s | 11:45 |
| HIIT 30/30 (built-in) | 16 | 0:30 / 0:30 | 5 s | 15:35 |
| 45/15 custom | 10 | 0:45 / 0:15 | 10 s | 9:55 |
| 3 minutes on, 30 s rest | 6 | 3:00 / 0:30 | 10 s | 20:40 |
| CF Intervals (built-in) | 10 | 1:00 / 0:30 | 5 s | 14:35 |
The 40/20 and 30/30 formats are already built in under the HIIT chip, so you only need Custom Timer for other values, such as a 30/15 or 45/15.
Ranges and limits
| Setting | Range | Step |
|---|---|---|
| Rounds | 0 (unlimited) to 99 | 1 |
| Round | 10 s to 30:00 | 5 s |
| Rest | 0 to 10:00 | 5 s |
| Prep | 0 to 60 s | 5 s |
| Warning | 0 to 30 s | 1 s |
- Every round has the same length, and every rest too: no pyramids, ladders or different exercises with different times in one timer.
- Prep runs only once, before round 1.
- Saved presets can't be edited. To change one, build it again and delete the old one (long-press > Delete). Each time you open Custom Timer it starts from the defaults: 3 rounds, 3:00, 1:00 rest, 10 s prep, 10 s warning.
- The free version keeps one saved preset; saving a second one needs Pro. Use Once stays free and unlimited.
- With Rest at 0, the end-of-round bell and the next round's bell ring back to back.
Tips
- Short intervals: a 5-second warning is plenty; on 3-minute rounds, 10 seconds works well.
- Want to know what you did this week? Each session is saved with its active time in History.
Questions and answers
Can I save more than one custom interval timer for free?
Can I set 3 minute intervals with 30 second rest?
Can I have a different rest after some rounds?
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