What this result means
1K repeats sit on the track or the road. This page locks work distance at 1.000 km. Pace, reps, rest. The interval workout calculator is the generic version.
1500m pace is a race clock, not a repeat set. Training-pace VDOT interval bands can suggest the pace you type here.
6 × 1K at 3:50/km with 2:00 rest: 3:50 each, work 23:00, rest 10:00, session 33:00, work 6 km.
Cruise 1Ks at threshold are slower than 400m repeat pace. Enter the pace you mean.
5 × 1K at 4:00/km with 90 s rest is 4:00 per rep, 20:00 of running, 6:00 of rest, and 5.0 km of work. A kilometre is 2.5 laps of 400 m.
Calculation method
Work time = 1 km × seconds per km. Session totals use rest × (reps − 1).
Exact arithmetic.
A “1K” on a short GPS loop is not 1000 m. A track 1000 m is 2.5 laps from a measured start.
Frequently asked questions
How many laps is a 1K?
Two and a half laps of 400 m.
What is 5 × 1K at 4:00/km with 90s rest?
4:00 each, 20:00 work, 6:00 rest, 26:00 session, 5 km work.
Can I use mile pace?
Yes. Switch the header to miles and enter min/mile. Internally the work is still 1.000 km.
Should I use the interval workout calculator instead?
Use that page when the work distance is not 1 km. This page locks 1.000 km so a 1K repeat session has its own landing. 1500 m race pace is a different tool.