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One Rep Max Calculator

Calculate your estimated one rep max (1RM) for any lift. Enter the weight you lifted and how many reps you completed to get your strength benchmark.

Select lift

Weight lifted (kg)

Reps completed

What is 1RM?

Your one rep max is the maximum weight you can lift for a single repetition with proper form. It's the universal benchmark for measuring strength.

Formula used

We use the Epley formula — the most widely used 1RM estimation method:

Weight × (1 + Reps ÷ 30)

How to use your 1RM

90-95%Heavy singles and doubles — strength peaking

75-85%Main work sets — strength and hypertrophy

60-75%Volume work and technique refinement

Note: This is an estimate. Actual 1RM varies by lift, fatigue level, and technique. Never attempt a true 1RM without a spotter.

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