One Rep Max Calculator
This one rep max calculator helps lifters estimate top strength and practical training loads from a challenging set.
Enter your numbers and review the live output
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Understand what this tool measures
It is built for lifters who want a practical estimate from a recent working set instead of testing a true max every time. The page adds rep-range equivalents so the result can support actual programming, not just a headline strength number.
Enter the weight lifted and reps completed to estimate one-rep max using the Epley formula, plus suggested equivalent weights for 2 through 10 reps.
What it measures
This calculator measures the core health or fitness estimate behind one rep max calculator and puts it into readable context.
What affects the result
Body size, activity, timing, and the chosen assumptions are usually what move the result the most.
How people use it
People use the output as a starting point for planning habits, nutrition, recovery, or training rather than as a perfect standalone verdict.
How to keep the result
This one rep max calculator supports shareable URL state, so the current inputs can be copied into a link and reopened later without re-entering the scenario.
What the result means
One Rep Max Calculator pairs the number with plain-language context so users can interpret the result more responsibly and use it as a starting point for planning.
How people use this calculator
Programming a top set
Estimate a likely one-rep max from a recent set of five.
The calculator converts the working set into a useful strength estimate.
Building rep targets
Use the rep table to pick approximate loads for higher-rep training.
You get a fast reference for 2-10 rep estimates.
Calculator feedback
Tell us if this calculator is working well
Use quick feedback if the result looks right or flag an issue if something seems off. Reports include the current calculator URL so the scenario can be reviewed.
Common questions
Which one-rep-max formula is used?
This calculator uses the Epley formula, one of the most common strength-estimation formulas for moderate rep ranges.
Is the one-rep-max estimate exact?
No. It is a useful estimate that can guide training, but fatigue, technique, and exercise selection all affect real-world max strength.
Why show 2-10 rep estimates too?
Because most training happens below a true max, so equivalent rep-range loads are often more useful than the 1RM number itself.
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