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Pace calculator + age-grade

Enter a recent time and get your training paces, race predictions, and age-graded performance — instantly, in your browser.

1 · Your runEnter the details of a recent effort
Race distance
Your time

h

min

s

Sex

Total ascent of the run in meters. Leave 0 for flat.

Computed locally, nothing is stored or sent to a server.

2 · Your resultsUpdates live as you type — no button to press

Estimated VMA

13.5 km/h

Your age-grade score

100% = the age-graded world record for your age and sex at this distance. Not a population percentile — a comparison to the best possible.

506070809054.0%
Average club50–59%

Computed locally via a polynomial approximation of the WMA road tables (±1.5%).

Your training paces

min/km — use these as your daily training targets

  • Recovery6:49 – 7:23
  • Easy5:55 – 6:31
  • Tempo5:02 – 5:24
  • Intervals4:13 – 4:40

Race predictions

What you could run on a flat course at the same fitness level (Riegel extrapolation).

  • 5K23:59
  • 10K(Your time)50:00
  • Half Marathon1:50:19
  • Marathon3:50:01

For the predictions below — adjusts times for a hilly target.

Want a full adaptive plan?

Coach Alex turns these paces into a personalized training plan, delivered on WhatsApp. Adaptive, deterministic, free during beta.

Start free trial →

Frequently asked questions

How is VMA calculated?

We extrapolate from your entered time using the Riegel formula (T2 = T1 × (D2/D1)^1.06) to estimate the pace you could sustain for a 6-minute maximal effort. That is your VMA. The value is clamped between 5 and 28 km/h.

What does the age-grade score mean?

100% equals the world-record-equivalent for your exact age and sex at this distance, based on the World Masters Athletics road tables. It is NOT a population percentile — there is no implied "you are faster than X% of runners". It is purely a comparison to the best possible performance.

How precise is the elevation correction?

We use the Minetti energy-cost polynomial to convert your D+ into a flat-equivalent time. The model only knows the total ascent of your run, not the full course profile, so it is an estimate. A 10K with 500m D+ on rolling terrain will read a few percent off compared to a GPX-based analysis. GPX upload is planned for V2.

Is my data stored?

No. Everything you type into the calculator stays in your browser. The math runs locally; there is no API call. The only thing sent to a server is the page request itself.

Why do the pace zones look different from my watch?

Watches use heart-rate zones derived from your tested or estimated HRmax/HRrest. We derive pace zones from your VMA — a fitness-anchored measure. The two are complementary: VMA-based paces tell you what speed to run at; HR zones tell you how hard your body is working. Use them together.