10K Erg Time Predictor
By the Watta Team · Updated
Enter a recent result at a shorter distance and get a 10K prediction using Paul's Law. A 7:00 2K predicts a 10K of about 38:52; a 19:30 5K predicts 40:40.
10K Time Predictor
Paul's Law: about 5 seconds per 500m slower for every doubling of distance. A rule of thumb for trained rowers — your own aerobic/anaerobic balance can move the result by several seconds per 500m.
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The 10K a 2K result predicts
Computed with the same functions as the calculator above, so the two cannot disagree.
| 2K time | Predicted 10K | 10K split |
|---|---|---|
| 6:30 | 36:22 | 1:49.1 |
| 7:00 | 38:52 | 1:56.6 |
| 7:30 | 41:22 | 2:04.1 |
| 8:00 | 43:52 | 2:11.6 |
| 8:30 | 46:22 | 2:19.1 |
Over a doubling this far from the tested distance the estimate widens: treat it as a starting pace to hold and adjust, not a target to chase from the first stroke.
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About This Calculator
The 10K erg time predictor estimates your 10,000-metre rowing ergometer performance from a shorter distance result using Paul's Law. The 10K is one of the most popular endurance tests on the Concept2, taking 35–45 minutes at competitive levels and relying heavily on aerobic capacity. Paul's Law says the sustainable /500m split slows by about 5 seconds for every doubling of distance: from 2K to 10K is 2.32 doublings, so a 7:00 2K (1:45.0 split) predicts a 10K split of about 1:56.6. Predictions from 5K or 6K results carry less uncertainty than predictions from a 2K, because those distances share the 10K's energy-system profile.
How This Works
Enter a known distance and your time for it. The calculator converts the result to a /500m split, adds 5 seconds per 500m for every doubling of distance up to 10,000m (Paul's Law), and converts the predicted split back to a total time. Every doubling adds the same 5 seconds, so the slowdown from 2K to 10K is about 11.6 seconds per 500m.
Formula
Examples
A rower with a 7:00 2K time
Predicted 10K time is approximately 38:52, with an average split of about 1:56.6/500m.
A rower with a 19:30 5K time
Predicted 10K time is approximately 40:40, with an average split of about 2:02.0/500m — one doubling, so 5 seconds per 500m slower than the 5K split of 1:57.0.
An elite rower with a 6:00 2K time
Predicted 10K time is approximately 33:52, with an average split of about 1:41.6/500m.
Worked examples are generated from the same formulas as the calculator above.
Benchmarks
| Level | Value |
|---|---|
| Elite male | Sub-31:00 (1:33.0 split) |
| Collegiate male | 32:00–35:00 (1:36.0–1:45.0 split) |
| Club male | 35:00–40:00 (1:45.0–2:00.0 split) |
| Elite female | Sub-35:00 (1:45.0 split) |
| Recreational | 40:00–50:00+ (2:00.0–2:30.0 split) |
More reference tables — 2K, 5K and 500m standards, watts by level, stroke rates and a split-to-watts table — are on the Stats & Benchmarks page.
In the Watta App
Watta keeps a 10K personal best per machine and shows each attempt against your previous one, so a prediction from this page can be checked against the real piece.
Frequently Asked Questions
How accurate is a 10K prediction from a 2K time?
What is a good 10K erg time?
Should I pace a 10K differently to a 2K?
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