One rep max calculator (1RM)
Estimate your one-rep max (1RM) on bench press, squat or deadlift with the Epley, Brzycki and Lombardi formulas and see the weight for each percentage and rep count.
What is your one-rep max?
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One rep max calculator (1RM): what it is for
Enter the weight and how many reps you did with it. The calculator estimates your one-rep max from the average of three formulas and shows the weight for each percentage of 1RM, with the approximate number of reps, to plan your training.
How to use
- Type the weight lifted.
- Enter the reps done.
- Use the percentage chart in your training.
When to use it
- Plan strength and hypertrophy training.
- Track progress on bench press and squat.
- Avoid risky max tests.
Frequently asked questions
What is 1RM?
It is the heaviest weight you can lift a single time with correct form. It is used as a reference to build percentage-based programs, like 75% of 1RM for sets of 8 to 10 reps.
Which formula is most accurate?
They are all estimates and work best up to 10 reps. Epley and Brzycki give similar results between 2 and 10 reps; the calculator shows the average of the three.
Is it safe to test a true 1RM?
Max tests require warming up, good technique and a spotter. For most people, estimating 1RM from a set of 3 to 8 reps is safer.
Is it really free?
Yes, 100% free. No sign-up, no subscription and no usage limits. All Tools123 tools are free and run right in your browser.