Health & Fitness
One Rep Max Calculator
Use this one-rep max calculator to estimate max strength without testing a true maximal lift.
Estimated 1RM
—
- Epley
- —
- Brzycki
- —
Student quick launch
Grade planning, algebra checks, and formulas students reach for most.
Study path
Use this calculator with
Follow these when you want the formula behind the answer, a short lesson, or nearby tools in the same topic.
What the one rep max calculator solves
Use this one-rep max calculator to estimate max strength without testing a true maximal lift.
Formula
How to use it
- Enter the weight lifted.
- Enter reps completed with good form.
- Use the estimate for training percentages, not ego lifting.
How to read the answer
The estimate is most useful for programming submaximal training loads.
Common mistakes and edge cases
- Do not max out without safe setup and experience.
- High-rep sets are less precise.
- Different lifts and athletes vary.
Worked examples
Five-rep set
Estimated 1RM
212
Single rep
Estimated 1RM
225
Frequently asked questions
Which 1RM formula is best?+
No formula is perfect. Epley and Brzycki are common and usually close for lower reps.
Can beginners use this?+
Yes for rough planning, but technique and safety matter more than max estimates.
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Last updated: May 8, 2026