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Critical Swim Speed Pace Calculator

CALCULATE YOUR CSS PACE

Enter your recent 200 and 400 time trial times to compute your CSS pace per 100.

Not sure how to test? See the steps ↓

HOW TO TEST YOUR CSS PACE

1
Warm up properly.
Get your body ready to swim fast with a good warm up.
2
Swim your 400 time trial.
Start from a push (not a dive) and give it your best sustained effort. Record your time.
3
Rest completely.
Take as much time as you need to fully recover. You should feel fresh and ready for the 200.
4
Swim your 200 time trial.
Start from a push and go all out! This should be faster than your 400. Record your time.
5
Calculate your CSS pace.
Take your 400 and 200 times and plug them into the calculator.