One Rep Max (1RM) Calculator
Calculator ToolsEstimate your max lift and training weights
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History
All history →One Rep Max (1RM) Calculator — at a glance
Find your estimated max lift without testing it.
80 kg × 6 reps
Calculate 1RM
Estimated 1RM
How to use it — step by step
The weight you lifted and how many reps you did (up to 12 is most accurate).
1
Enter your values
Fill in the fields. Default numbers are shown so you can see how it works.
2
Press Calculate 1RM
The answer appears at once as large result cards.
3
Copy or share
Copy the result, or share a link that opens with your numbers filled in.
Pro tips
Small things that make the result better.
✦Results are most accurate for 10 reps or fewer.
✦Use a spotter when you test heavy lifts.
✦Percent rows help plan sets.
Quick facts
Freeno signup
Privateruns in your browser
Instantresult in a second
No limituse it as often as you like
Frequently Asked Questions
Which formula is best?+
They give close results at low reps. The average of three is shown first.
Is it safe to test my max?+
Only with good form and a spotter. The estimate lets you avoid maxing out.
Is my data safe?+
Yes. Everything runs inside your own browser. Your text, files and images are never uploaded to any server.
Is this tool really free?+
Yes — completely free, no signup, no watermark and no usage limit.
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