How to use
- Enter the inputs.
- Sanity-check the outputs.
- Use the result as a planning anchor, not a promise.
Jump to
Tool
Inputs → outputs
This page is intentionally practical: get numbers first, then read the how-to.
Inputs
- • Distance (km/mi)
- • Finish time (hh:mm:ss)
- • Split every (km/mi) (optional)
Outputs
- • Pace per km
- • Pace per mile
- • Split table
Export
Print or share the tool
Useful outputs beat generic SEO copy. Print a PDF or share this page before race week.
Tip: print or save as PDF for race week.
Example presets
Prefill with a realistic scenario
Pick an example to prefill the calculator, then tweak inputs for your own training week.
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Quick answers
The 60-second version
Snippet-ready answers to common questions. Use the calculator above for the numbers.
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.
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
What can break it
- • 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.
Related
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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.
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