Compare calculators

Both calculators run independently — change the inputs on either side to compare results.

One Rep Max Calculator

Estimate the maximum weight you can lift for a single rep from a sub-maximal set. Use it to set training zones, track strength progress, or compare lifts across exercises.

Weight Lifted (lbs)

Repetitions Performed (reps)

Calculation Formula

Fill in the required fields to see your result.

Sports

Marathon Time Predictor

Predict your full marathon finish time using your recent 10K result and training level. Useful for race-day pacing plans and training block goal-setting.

Reference Race Distance

Race Time (Hours) (h)

Race Time (Minutes) (min)

Race Time (Seconds) (sec)

Weekly Training Mileage (km)

Marathon Experience

Fill in the required fields to see your result.

Key differences

	One Rep Max Calculator	Marathon Time Predictor
Category	Sports	Sports
Inputs required	3	6
Result	Estimated 1RM (lbs)	Predicted Marathon Time (minutes)
What it does	Estimate the maximum weight you can lift for a single rep from a sub-maximal set. Use it to set training zones, track strength progress, or compare lifts across exercises.	Predict your full marathon finish time using your recent 10K result and training level. Useful for race-day pacing plans and training block goal-setting.