Introduction
The Ultimate Erg Calculator (UEC) attempts to combine as many useful erging calculations in one place. As you enter values and move from one cell to another additional values are calculated wherever possible.
For example, enter a distance and a split and the UEC will show time (and watts); enter a split and time and the UEC will show distance. Similarly, if you have entered a distance and time the average split and watts will be shown. If you then enter a stroke rate, distance per stroke (DPS) and stroke power index (SPI) are calculated. And so on.
If you have entered values for distance and time a split is calculated. If you then edit the split UEC doesn't know whether you want to modify distance or time, i.e., predict a new time for that distance or predict a new distance for that time! For this reason nothing happens when you edit the split until you click in either the distance or time field.
If you need any guidance or have ideas about improving the UEC please feel free to email me: walt(at)brookhouse(dot)co(uk).
Watt %ages
If you want to know what the split is for a percentage of a given wattage, enter a value in the Watts box like so: 300%70. The corresponding split is shown in the Split box.
To calculate a time for a different distance based on a watt percentage enter a value in the watt field in the form 300%70. This will update the split value. Enter a new value in the distance field and the time field will then be updated.
Predictors
Everyone loves a predictor! As we all know, the best predictor is rowing the distance as hard as you can. Sometimes, though, you need a guide to pace based on a known performance at a different distance.
The bottom tier of the UEC includes two predictors: a) a 2K prediction based on a 30r20; and b) Paul's Law.
30r20
It is generally held that a 30R20 can be completed at 70% of 2K watts. If you enter a 30R20 result in time/distance, and rate 20, the UEC will show your predicted 2K time.
Paul's Law
(Thanks to Paul Smith www.ps-sport.net)
Paul's Law says that if you double the distance the 500m split increases by five seconds for a rowing athlete with balanced speed/endurance capability. Strictly speaking, Paul's Law isn't a predictor but rather serves to highlight whether you need to work on speed or endurance.
Enter a known time and distance in the UEC, and select a different distance from the Paul's Law dropdown. The UEC will update to show the time and split/watts for that distance that conforms to Paul's Law.
To get a table of Paul's Law results from the current time/distance click the 
more arrow next to the "Paul's Law" label.
Lactate Training Band (LTB) Spreadsheet
The LTB spreadsheet is another useful predictor base on watt %ages of a current 2K time. My own comparison shows that Paul's Law and the LTB spreadsheet yield equivalent
predictions to a fraction of 1%. If you click the more arrow next to Watts
you can see the percentage figures that the LTB spreadsheet uses for various distances.
Note: the LTB percentages are relative to a current 2K so keep that in mind.