Open Pace Dataset
The whole pace-to-finish-time matrix as one file, free to reuse with attribution.
Two files, 73 rows each, covering every pace from 3:00 to 9:00 min/km in 5-second steps. Each row gives the pace per mile, the speed in kph and mph, and the finish time over twelve distances from 1500m to the marathon. Licensed CC BY 4.0: use it anywhere, keep the credit to paceslab.com.
What is in the file
| Column | Meaning |
|---|---|
| pace_min_km | Pace as M:SS per kilometre, the row key. |
| pace_seconds_per_km | The same pace as an integer number of seconds, for machine use. |
| pace_min_mile | Equivalent pace per mile, converted at exactly 1.609344 km per mile. |
| speed_kph, speed_mph | Average speed at that pace, to four decimal places. |
| 1500m through marathon | Twelve finish-time columns: 1500m, 1 mile, 3000m, 5K, 8K, 10K, 12K, 15K, 10 mile, half marathon, 30K and marathon. |
Licence and attribution
Creative Commons Attribution 4.0. You may copy, redistribute, adapt and build on this file, including commercially, provided you credit PaceLab (paceslab.com). A link is the easiest way to do that. No permission request is needed and no key is issued, because there is nothing to authenticate against.
Reproducing it yourself
The whole file is two multiplications, and that is the point: the numbers are checkable. Finish time in seconds equals the pace in seconds per kilometre times the distance in kilometres. Speed in kph equals 3600 divided by the pace in seconds per kilometre. Pace per mile equals pace per kilometre times 1.609344. The generator that produces the published file lives in the repository as scripts/gen-dataset.mjs, and the constants and rounding rules are set out on the methodology page.
Why a file and not an API
PaceLab is a static site. Nothing you type into a calculator is sent anywhere, because there is nowhere to send it, and that is a promise worth more than a query endpoint. A static dataset keeps that property intact while still giving developers, coaches and race organisers something to build on. If you want the calculator itself on your own site rather than the numbers, the embed page has copy-paste code.
Frequently asked questions
Is there an API?
No, and there is not going to be one. PaceLab is a fully static site with no backend, which is what lets it make the privacy promise it makes. A downloadable file gives you the same numbers, works offline, and can be checked and re-hosted, which a query string cannot.
Can I use this dataset commercially?
Yes, under CC BY 4.0. Keep the attribution to PaceLab (paceslab.com) and you are done. No permission request needed.
How were these numbers produced?
Finish time is the pace in seconds per kilometre multiplied by the distance in kilometres. Speeds are 3600 divided by the pace in seconds per kilometre. Miles convert at exactly 1.609344 km. There is no estimation or modelling anywhere in this file.
Why does the file stop at 9:00 min/km?
Because past that the arithmetic is trivially extendable and the file is not the interesting part any more. If you need a wider range, the method above reproduces any row in one line of code.
Last reviewed . Formulas, constants and sources: methodology. Changes to any calculation are logged in the changelog.