Training estimates

One Rep Max Calculator

Estimate one-rep max strength from weight lifted and repetitions. Use this Fitness and training tool to enter your numbers, review the result, and understand the key assumptions before making the next decision.

What you get
A focused calculator, clear explanation, common questions, and useful next tools.
Quick intro
Calculator
Result
Explanation
Common questions
Related tools

Calculator tool

How this calculator works
The result depends on the numbers you enter and the assumptions shown below.

The estimate uses a common strength formula based on weight and repetitions performed.

Review the inputs carefully and treat the output as an estimate. For decisions involving money, taxes, health, law, or security, compare the result with trusted professional guidance when needed.

Frequently asked questions

Is one-rep max exact?

No. It is an estimate and can vary based on form, fatigue, and training experience.

Should beginners test max lifts?

Beginners should avoid unsafe max testing and use conservative estimates.