1 Rep Max Calculator

Calculate your One Rep Max using weight and reps based on the Epley formula.

Enter Lift Details

1RM = W × (1 + R/30)

Recent Calculations

See what others have calculated recently

Result

96 from epley
Weight:80
Reps:6
desktop12/25/2025

Result

  • Tool Name: 1RM Calculator
  • Result: 92.92 from brzycki
  • Weight: 80
  • Reps: 6
Weight:80
Reps:6
desktop12/25/2025

Result

  • Tool Name: 1RM Calculator
  • Result: 96 from epley
  • Weight: 80
  • Reps: 6
Weight:80
Reps:6
desktop12/25/2025

Result

96
Weight:80
Reps:6
desktop12/25/2025

Result

93.33
Weight:80
Reps:5
mobile12/16/2025

Result

116.67
Reps:5
Weight:100
desktop12/15/2025

About 1 Rep Max Calculator

The 1RM Calculator helps you estimate your One Rep Max (1RM) — the maximum weight you can lift for a single repetition of an exercise — based on the weight you lifted and the number of repetitions you performed. This tool uses widely accepted strength estimation formulas to provide a safe and practical strength assessment without requiring you to test your actual maximum lift.

Unlike attempting a true maximal lift, which can be risky and time-consuming, this calculator uses formulas like the Epley and Brzycki equations to predict the maximum weight you could lift for one repetition based on submaximal performances. This makes it ideal for planning training loads and tracking strength progress.

Why Use This Tool

The 1RM Calculator is built to help strength trainers, athletes, and fitness enthusiasts gauge their maximum strength levels and tailor their workouts accordingly. It provides a practical strength metric that is useful for setting training intensity and tracking improvements over time.

It is especially useful for:

  • Estimating your maximum strength safely without testing true 1RM
  • Planning training loads based on percentage of 1RM
  • Tracking strength progress over time
  • Comparing strength across different exercises or training phases

The 1RM Calculator is designed to be:

  • Fast and intuitive — simple inputs with immediate results
  • Formula-based — uses Epley and Brzycki strength estimation formulas
  • Supportive for training — helps inform workout intensity
  • Helpful for all levels — useful for beginners and experienced lifters alike

How It Works

Understanding the process behind the tool

The calculator applies commonly accepted equations, such as the Epley or Brzycki formula, which are designed to predict maximum strength based on sub-maximal efforts. These formulas take into account how strength decreases as the number of repetitions increases and use that relationship to estimate what your one-rep maximum would be

Steps to Use

1

Enter your height & weight

2

Click calculate button

3

View BMI result instantly

4

Track results over time

Frequently Asked Questions

Get answers to common questions

What is a 1RM (One Rep Max)?

A One Rep Max (1RM) is the maximum weight you can lift for one repetition of a specific exercise with proper form. It’s a common measure of strength used in training programs and strength assessments.

How does the 1RM Calculator work?

This tool uses established strength estimation formulas such as the Epley and Brzycki equations to predict your maximum lift based on the weight lifted and the number of repetitions performed.

Can I use this calculator for any exercise?

Yes, the 1RM Calculator can be used for most strength exercises such as bench press, squat, deadlift, and others where you know the weight and reps performed.

Is the estimated 1RM always accurate?

The estimate provides a useful approximation of your maximal strength, but it may vary slightly from your true 1RM due to individual factors like technique and fatigue.

Why not test my actual 1RM?

Testing your actual 1RM requires lifting maximal weight with proper form, which can be risky without supervision. Estimation via calculator helps reduce injury risk while giving actionable strength data.

Should I use this calculator regularly?

You can use the 1RM Calculator periodically to track strength progress and adjust training loads based on improvements.