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CalculatorsFitness & Training1RM Calculator
Verified Formula
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1RM Calculator

Calculate your one-rep maximum for any lift.

Biometric Inputs

Real-time clinical computation active

Awaiting Data
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Enter biometric metrics to generate report

This assessment provides statistical probability and mathematical interpretation based on validated clinical equations. It is not a diagnostic tool.

Scientific Context

Estimate the maximum weight you can lift for a single repetition based on sub-maximal performance.

Mathematical Formula

Brzycki Formula: Weight / (1.0278 - 0.0278 * Reps)

Behind the Math

The Brzycki formula, developed in 1993, is one of the most widely cited equations in exercise physiology for predicting 1RM when a true maximal lift is unsafe or impractical.

Expert Tip

The more reps you do, the less accurate the prediction becomes. For the best accuracy, try to perform a set of 3 to 5 reps with good form rather than a high-rep set (10+).

Primary Use
Health Screening
Standard
WHO Guidelines
Complexity
Clinical Grade

Frequently Asked Questions

Metric Recommendations

VO2 Max Estimator

Estimate your aerobic capacity (cardio fitness).

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Calculate daily protein needs for your activity level.

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Optimize protein, fat, and carb ratios.

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Total Daily Energy Expenditure based on activity.

Target Heart Rate

Ideal heart rate zones for exercise.

Calories Burned

Calories burned by activity and duration.

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