How to use the rowing split calculator
- Choose Total time to start from a split, or 500 m split to start from a total time.
- Enter the split per 500 m like 2:00, or the total time like 8:00, and the distance in meters.
- Open Advanced options if you need to change the watts constant.
- Read the split, total time, power in watts and speed, and the table of times at other distances.
Formula
Total time = split / 500 x distance. Split = total time / distance x 500
Pace = split / 500 (seconds per meter). Speed = 500 / split (meters per second)
Watts = constant / pace cubed, with the constant 2.8 unless you change it
Times are shown to a tenth of a second, rounded half up. Speed in km/h is m/s x 3.6, and in mph it is km/h / 1.609344.
A 2:00 split over 2,000 meters
A split of 2:00 is 120 seconds per 500 m. Over 2,000 m that is 120 / 500 x 2,000 = 480 seconds, or 8:00.0. The speed is 500 / 120 = 4.17 m/s, which is 9.32 mph.
The pace is 120 / 500 = 0.24 seconds per meter and 0.24 cubed is 0.013824, so with the constant 2.8 the power is 2.8 / 0.013824 = 202.5, shown as 203 W. A faster 1:45 split over 5,000 m takes 105 / 500 x 5,000 = 1,050 seconds, or 17:30.0, at about 302 W.
The power formula
Indoor rowing machines show power in watts from the pace, using the fact that the work needed to move a boat grows with the cube of the speed. A commonly quoted form of the formula is watts = 2.80 divided by the pace in seconds per meter, cubed. The constant 2.8 is an input here, not a fact this page can vouch for, so if your machine documents another value, enter it under Advanced options.
Because speed is cubed, small changes in split make large changes in power. Going from 2:00 to 1:55 is about 4% faster in speed but is roughly 14% more power by this formula. Do not expect the same numbers on a rowing machine of another brand.
Splits and total times
A split is the time for 500 meters at your current pace, and the total time is the split scaled to the distance. The calculation assumes a steady pace over the whole distance, which is rare in a real piece, so use it to set a target split and then compare with your results. Times are accepted as m:ss, m:ss.t, h:mm:ss or plain seconds, and the tool shows a table of common distances for the split you chose.
This page is arithmetic only and is not training or health advice. Related tools include the pace calculator, the power to weight ratio calculator, the time calculator and the average calculator.
Assumptions and limits
- The pace is steady over the whole distance.
- Watts are worked out with the constant you enter, 2.8 by default, which you can change in Advanced options.
- Distance is in meters, and 500 m splits are used.
- Times are rounded half up to a tenth of a second.
Frequently asked questions
How do you calculate a 500 m rowing split?
Divide the total time by the distance in meters and multiply by 500. An 8:00 time over 2,000 m is a 2:00 split.
How are watts worked out from the split?
The tool divides a constant, 2.8 by default, by the pace in seconds per meter cubed. A 2:00 split gives about 203 W.
Why change the watts constant?
Machines can use different constants. If the maker of your rowing machine states another value, enter it so the watts match the display.
What format does the time accept?
Use m:ss like 2:00, m:ss.t like 1:58.5, h:mm:ss like 1:05:00, or plain seconds.