Mobile App
Seconds Interval Timer
The full Seconds experience — on iPhone, Apple Watch, and Android.
Stack multiple timers into a single multi-block session. Chain a warm-up flow, a strength circuit, and a HIIT finisher together with rest between blocks — the compound timer runs the whole stack as one workout.
A HIIT block followed by a circuit block, chained with a minute of rest. The compound timer runs every nested timer in order before looping the stack for the next cycle.
A four-station strength circuit followed by a short HIIT finisher. Build the work, then burn it out — a complete gym-day stack in under twenty minutes.
Three timers chained back-to-back: a mobility warm-up, a HIIT main block, and a stretching cooldown. One press, one continuous flow from prep to recovery.
Bike intervals straight into run intervals — the classic triathlete brick. Two HIIT blocks chained back-to-back to train the transition under fatigue.
A compound timer is a stack of complete interval timers run as one workout. Each block in the stack is a full timer in its own right — a circuit of stations, a HIIT block of work and rest rounds, a custom sequence of intervals — and the compound timer chains them together with a timed rest between blocks. Press start once and the session flows from the first block to the last without you touching the clock.
The stack itself can also cycle: set it to run more than once and the timer repeats the whole sequence of blocks, with a separate rest between cycles. Add a warmup before the first block and a cooldown after the last, and the entire session — prep, work, recovery — lives in a single timer.
A single circuit forces the whole workout into one shape: the same stations, the same rotation, the same rest pattern throughout. Most real sessions are not one shape. A gym day might be a paced strength circuit followed by a flat-out conditioning finisher; a class might be a mobility warmup, a main block, and a stretching cooldown. Each part wants its own structure, durations, and rest — which is exactly what a compound timer gives it.
The chaining matters as much as the structure. The transition between blocks is a timed rest, not a pause, so the next block starts automatically — the finisher you would normally skip begins before you can negotiate with it.
Think in blocks before intervals. Name the parts of your session — warmup, strength, conditioning, cooldown — then build each part as the timer type that fits it: a circuit for rotating stations, a HIIT block for a fixed work-to-rest ratio, a custom timer for a free-form sequence like a stretching flow.
Then set the rest between blocks to match the transition you actually need: long enough to rack the weights or change shoes, short enough that you do not go cold. Because each block stays a separate timer inside the stack, you can edit or replace one without touching the others.
If your whole workout is one rotation of stations, use a circuit timer. If it is one work-to-rest ratio repeated, use a HIIT timer. If it is a single free-form list of intervals, use a custom timer. Reach for the compound timer when the session has distinct parts with different shapes — that is the structure none of the single timers can express.
The presets above show the range: a strength circuit with a HIIT finisher, a warmup-work-cooldown frame, and a triathlon brick that chains bike intervals into run intervals. Start one as-is, or open it in the editor and stack your own blocks.
Fixed work/rest intervals, repeated for a set number of rounds.
Rotate through named exercises with optional breaks. Stations of any duration.
Back-to-back HIIT blocks — every round of one exercise, then on to the next.
Simple timed rounds with breaks. Boxing, MMA, sparring.
Build any interval sequence from scratch, one by one.
The full Seconds experience — on iPhone, Apple Watch, and Android.