Free tool

1RM calculator

Estimate your one-rep max (1RM) from weight and reps using the Epley formula. Same approach as Refyuel Health OS strength tracking. Educational only.

Enter the weight you lifted and how many reps you completed. The Epley formula estimates your 1RM; it is most reliable for roughly 1-10 reps.

Estimated 1RM

e1RM = weight × (1 + reps / 30). Not a substitute for a true max test.

Estimated 1RM: 116.7 kg

Training weights at reps

5 reps~100 kg
8 reps~92.1 kg
10 reps~87.5 kg

Track sets, reps, and strength PRs in Refyuel Health OS.

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Educational estimate only - not medical or dietetic advice. Consult a qualified professional before changing diet or exercise. See our health disclaimer.

Related guides

Beginner Gym Plan for Your First 30 Days
How to Log Workouts for Progress (Without Overthinking It)
Progressive Overload and PR Tracking - A Simple Guide
Full Body vs PPL: Which Workout Split Fits Your Week?
Training Volume for Muscle Gain: Sets, Reps, and When to Add More

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