How to use
- Enter the inputs.
- Sanity-check the outputs.
- Use the result as a planning anchor, not a promise.
On this page
Your path
Perform on the day
The decision this page helps you make
Use pace as a visible planning anchor, then adjust it for terrain, conditions, fatigue, and the evidence from training.
Loading pace calculator…
Example presets
Prefill with a realistic scenario
Pick an example to prefill the calculator, then tweak inputs for your own training week.
Tool
What you enter and what you get
Enter a few details to get your result. The guide below explains how to use it.
You enter
- • Distance (km/mi)
- • Finish time (hh:mm:ss)
- • Split every (km/mi) (optional)
You get
- • Pace per km
- • Pace per mile
- • Split table
Assumptions
What this tool assumes
- • You run at a steady average pace (real races have pacing variation).
- • Splits are calculated on flat ground with no wind/terrain adjustments.
Limitations
When this estimate may be less reliable
- • Does not adjust for heat, hills, wind, crowding, or fatigue drift.
- • Race-day execution is effort-driven; use splits as a planning guide, not a rigid script.
Adaptive AI coach for iPhone
Meet your adaptive AI coach.
Tell your coach what you are training for. It builds the plan, follows the work you complete, and adapts upcoming training when recovery, your schedule, or real life changes.
FAQs
Should I pace evenly or negative split?
For most runners, a gentle negative split works best: start controlled, settle, then accelerate only if effort stays stable after 30K.
What pace should I use in training?
Train by effort zones and purpose: easy runs easy, workouts controlled, long runs mostly easy. Use this tool to translate goals into splits.
Why do my race splits drift?
Heat, hills, crowding, and fatigue drift all compound. Plan with splits, execute by effort and hydration/fueling.
Keep going
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