acalculator

What is my rowing split and watts?

Type any two of distance, time and split per 500 m. The rowing calculator works out the third with the indoor rower formulas, plus the average watts and the calories the monitor would show.

Your numbers

Units
Type up to two parts, for example 7 min 20 s.
For example 1 min 50 s.
Split
1:50.0 /500 m

Your split is 1:50.0 /500 m, 263 watts, finishing in 7:20.0.

Time
7.333 min
Finish time
7:20.0
Average watts
263
Calories per hour
1,204
Calories
147

Split: 1:50.0 /500 m. Your split is 1:50.0 /500 m, 263 watts, finishing in 7:20.0.

How to calculate

Computes an indoor rowing split per 500 m, finish time or distance from the other two, with Concept2’s formulas, plus the average watts and calories.

Example with the default inputs (Distance 2,000 m, Split per 500 m 1.83333333333333 min): Your split is 1:50.0 /500 m, 263 watts, finishing in 7:20.0.

Formula: split = 500 × time ÷ distance; watts = 2.80 ÷ (split ÷ 500)³ (split in seconds); calories per hour = 4 × watts ÷ 1.1639 + 300.

  • The formulas are Concept2’s for its indoor rowers; other machines may show other numbers for the same effort.
  • Calories use the monitor’s formula, built on a 175 lb rower with a resting rate of 300 Cal per hour.

Machine-readable copies: Markdown, JSON.

Worked examples

Each example is checked against the calculator on every build.

  1. Distance 2,000 m, Split per 500 m 1.833 min gives Time 7.333 min, Finish time 7:20.0, Split 1:50.0 /500 m, Average watts 262.96018.Source: 2,000 m at a 1:50 split is 7:20, https://www.concept2.com/training/pace-calculator (retrieved 2026-10-18)
  2. Distance 500 m, Time 2.083 min gives Split per 500 m 2.083 min, Average watts 179.2, Calories per hour 915.860469, Calories 31.800711.Source: A 2:05 split is 0.25 s/m and 179.2 watts, https://www.concept2.com/training/watts-calculator (retrieved 2026-10-18); Concept2, How To Use Your PM2/PM2+: Calories = (4 × average watts ÷ 1.1639) + 300 Cal/hour × time rowed in hours, https://www.concept2.com/support/monitors/pm2/how-to-use (retrieved 2026-10-18)
  3. Distance 6,000 m, Time 30 min gives Split per 500 m 2.5 min, Split 2:30.0 /500 m, Average watts 103.703704.Source: 2,000 m at a 1:50 split is 7:20, https://www.concept2.com/training/pace-calculator (retrieved 2026-10-18)

How it works

Type any two of the three boxes; the page fills the third. Times are in seconds inside the formulas, distances in meters.

  • Split (seconds per 500 m) = 500 × time ÷ distance
  • Time = split × distance ÷ 500
  • Distance = 500 × time ÷ split
  • Watts = 2.80 ÷ (split ÷ 500)³
  • Calories per hour = 4 × watts ÷ 1.1639 + 300
  • Calories = calories per hour × time ÷ 3,600

Rounding. The split and finish time show as m:ss.t (h:mm:ss.t from an hour up), rounded to the tenth of a second, halves up. Watts show with at most 1 decimal, trailing zeros left off; calories per hour and calories as whole numbers.

Assumptions

  • The formulas are Concept2's for its indoor rowers (RowErg).
  • The calorie rate assumes a 175 lb rower with a resting rate of 300 Cal per hour, as the monitor does.
  • The distance is 1 m to 1,000 km; the time 1 s to 240 hours; the split 30 s to 1 hour.

Worked examples by hand

2,000 m at a 1:50 split. Time = 110 × 2,000 ÷ 500 = 440 s = 7:20.0. Watts = 2.80 ÷ (110 ÷ 500)³ = 2.80 ÷ 0.010648 = 262.96, shown as 263 W.

500 m in 2:05. Split = 500 × 125 ÷ 500 = 125 s (2:05.0). Watts = 2.80 ÷ 0.25³ = 179.2 W. Calories per hour = 4 × 179.2 ÷ 1.1639 + 300 = 916; for 125 s that is 915.86 × 125 ÷ 3,600 = 32 Cal.

6,000 m in 30 minutes. Split = 500 × 1,800 ÷ 6,000 = 150 s (2:30.0). Watts = 2.80 ÷ (150 ÷ 500)³ = 2.80 ÷ 0.027 = 103.7 W.

Other questions people ask

How do I calculate my rowing split?

Divide the time by the distance and multiply by 500. 2,000 m in 7:20 (440 seconds) is 440 ÷ 2,000 × 500 = 110 seconds, a split of 1:50 per 500 m.

What is a 2k split calculator?

It turns a target 2,000 m time into the split to hold, or a split into a finish time. A 1:50 split for 2,000 m finishes in 1:50 × 4 = 7:20. Type 2,000 m and either the time or the split.

How are watts worked out from the split?

Concept2 uses watts = 2.80 ÷ pace³, where pace is the split in seconds divided by 500 (seconds per meter). A 2:05 split is 0.25 s/m, so 2.80 ÷ 0.25³ = 179.2 watts.

Why does a small change in split mean a big change in watts?

Watts go with the cube of speed. Rowing 10% faster takes about 33% more power, because water and air drag grow fast with speed. Dropping from a 2:00 to a 1:50 split takes about 30% more watts.

How are rowing calories calculated?

The monitor uses Calories per hour = 4 × watts ÷ 1.1639 + 300. The 300 is a resting rate for a 175 lb rower, so it is the same for everyone. At 179.2 watts that is 916 Cal per hour.

Do these numbers work for other rowing machines?

The formulas are Concept2’s, for its indoor rowers. Other machines measure power their own way, so the same effort can show a different split there.