00:00
45-Second Timer
Forty-five seconds is the work half of the popular 45/15 interval format, where each round fits neatly into one minute. The timer below starts automatically.
45/15 circuit
Eight rounds of 45 seconds on and 15 seconds off — eight minutes, one exercise per minute.
Interval timer (work / rest rounds)
No active timers. Start one above or pick a preset.
Shortcuts: Space pause/resume · R reset · + add a minute · F fullscreen · Esc silence. They act on the timer that ends soonest.
45 seconds at a glance
- Started now, it ends at
- —
- In seconds
- 45
- In milliseconds
- 45,000
- In minutes
- 0.75
- Share of an hour
- 1.3%
- Share of a day
- 0.05%
- Back-to-back per hour
- 80
What a 45-second timer is good for
- 45/15 HIIT: 45 seconds of work, 15 seconds to switch exercises.
- Rest between sets of strength training, where 30–90 seconds is the usual range for moderate loads.
- A timed answer in interview or debate practice.
- Holding a yoga pose for several breaths.
45/15 circuit: the full routine
Eight rounds of 45 seconds on and 15 seconds off — eight minutes, one exercise per minute. Press Start 45/15 circuit above and the timer runs every step in order, with a short cue between steps and the current step in the browser tab title.
| # | Step | Length | Starts at |
|---|---|---|---|
| 1 | Work 1/8 | 45 s | 0:00 |
| 2 | Switch | 15 s | 0:45 |
| 3 | Work 2/8 | 45 s | 1:00 |
| 4 | Switch | 15 s | 1:45 |
| 5 | Work 3/8 | 45 s | 2:00 |
| 6 | Switch | 15 s | 2:45 |
| 7 | Work 4/8 | 45 s | 3:00 |
| 8 | Switch | 15 s | 3:45 |
| 9 | Work 5/8 | 45 s | 4:00 |
| 10 | Switch | 15 s | 4:45 |
| 11 | Work 6/8 | 45 s | 5:00 |
| 12 | Switch | 15 s | 5:45 |
| 13 | Work 7/8 | 45 s | 6:00 |
| 14 | Switch | 15 s | 6:45 |
| 15 | Work 8/8 | 45 s | 7:00 |
| Total | 7 min 45 s | ||
Need different lengths? Open Interval timer in the tool to set your own work, rest and round counts.
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