Half Marathon Pace Calculator

Calculate half marathon pace from a target finish time, including mile and kilometer paces and even cumulative splits.

Inputs and method

Enter finish time and choose split units. Pace and cumulative splits use the standard 21.0975 km half-marathon distance; calculations retain raw seconds and round split displays to the nearest second.

Interpreting the estimate

Use the result as a planning value and keep input precision consistent with the measurements or source data you have. Small displayed differences can come from final-place rounding; intermediate values are not rounded.

Assumptions and limits

Even pacing is an arithmetic plan, not a prediction or coaching prescription. Course measurement, terrain, weather, stops, and individual capacity affect actual splits.

Rejecting empty, invalid numeric, prohibited negative, zero-denominator, impossible, or unsupported inputs prevents the page from presenting a misleading numeric result.

Method basis

Pace and cumulative splits are publisher derivations from the stated 21.0975 km distance and entered finish time. The route does not provide race-day guidance.