Pace-to-Watts Calculator
Instantly convert between rowing split, power, speed, and calories. See how the cubic relationship shapes your training.
Enter Any Value
Power Output
302W
1:45.0 / 500m
Split
Power
Speed
Speed
Calories
Power Impact of Split Changes
How much extra power each 5-second split change costs from your current 1:45.0 pace:
Split vs Watts Curve
The cubic relationship means small pace gains at fast splits cost far more watts than the same gain at slow splits.
What If? Slider
Drag to see how split changes affect power output in real time.
Quick Reference Table
| Split /500m | Watts | km/h | Cal/hr |
|---|---|---|---|
| 1:30.0 | 480 | 20.0 | 1950 |
| 1:35.0 | 408 | 18.9 | 1703 |
| 1:40.0 | 350 | 18.0 | 1503 |
| 1:45.0 | 302 | 17.1 | 1339 |
| 1:50.0 | 263 | 16.4 | 1204 |
| 1:55.0 | 230 | 15.7 | 1091 |
| 2:00.0 | 203 | 15.0 | 996 |
| 2:05.0 | 179 | 14.4 | 916 |
| 2:10.0 | 159 | 13.8 | 847 |
| 2:15.0 | 142 | 13.3 | 789 |
| 2:20.0 | 128 | 12.9 | 738 |
| 2:25.0 | 115 | 12.4 | 695 |
| 2:30.0 | 104 | 12.0 | 656 |
Understanding the Concept2 Power Formula
Every Concept2 rowing machine calculates power using one formula:
Watts = 2.80 ÷ pace³
where pace = split time in seconds ÷ 500
For example, a 2:00.0 split means each 500 m takes 120 seconds. The pace factor is 120 / 500 = 0.24. Cubing that gives 0.013824, so watts = 2.80 / 0.013824 ≈ 203 W.
Why Is It Cubic?
The erg flywheel resists movement through air drag, which increases with the cube of speed. This mirrors how a boat moves through water: doubling your speed requires roughly eight times the power. In practical terms, going from 2:00 to 1:55 per 500 m costs about 30 extra watts, but going from 1:35 to 1:30 costs over 60 extra watts—for the same 5-second improvement.
Calorie Calculation
The PM5 display uses this formula to estimate calories per hour:
cal/hr = 300 + (4 × watts ÷ 1.1639)
This assumes a rower weighing approximately 175 lb (80 kg). Your actual energy expenditure will differ based on body weight, fitness level, and rowing efficiency. For a weight-adjusted estimate, try our Calories Burned Calculator.
Common Split/Watts Benchmarks
| Level | Split /500m | Watts | Context |
|---|---|---|---|
| Beginner | 2:30.0 | 104 | First weeks on the erg |
| Recreational | 2:10.0 | 159 | Regular training, steady state |
| Intermediate | 1:55.0 | 230 | Consistent 2K training |
| Advanced | 1:42.0 | 330 | Club/collegiate level |
| Elite | 1:30.0 | 480 | National/international athletes |
Related Tools
- Rowing Time & Split Calculator — predict finish times for any distance
- Race Pace Calculator — plan your race splits and pacing strategy
- Calories Burned Calculator — weight-adjusted energy expenditure
- Pace Chart — full reference table at every split
References
- Concept2 Watts Calculator — official Concept2 pace-to-watts tool
- Concept2 Calorie Calculator — official calorie estimation methodology