Max Bench Calculator
Estimate max bench press from weight lifted and repetitions.
Enter the weight successfully lifted for the rep set.
Use a whole number from 1 to 30. Lower-rep sets are usually more reliable.
Status: initial
Results
Awaiting calculation
Introduction
The Max Bench Calculator estimates bench press one-rep max from a set weight and rep count.
Purpose
Use this calculator for strength-training estimates and to compare training percentages with clear fitness assumptions.
One-rep max method
The calculator supports common 1RM formulas such as Epley, Brzycki, Lombardi, O'Conner, and an average of those estimates.
Variable explanations
The load successfully lifted for the full set.
The number of completed reps with proper range and control.
Choose pounds or kilograms. Results stay in the same unit.
The selected equation used to estimate one-rep max.
A suggested load based on a percentage of estimated 1RM.
Formula guide
Epley
1RM = weight x (1 + reps / 30)
- Weight is the completed set load.
- Reps are completed repetitions.
A common simple estimate for moderate rep ranges.
Brzycki
1RM = weight x 36 / (37 - reps)
- Best used for rep counts below 30.
A classic one-rep max equation used in many calculators.
Lombardi
1RM = weight x reps ^ 0.10
- Uses an exponent for rep adjustment.
Provides another perspective on rep-to-max conversion.
Worked examples
Bench press example
- Weight lifted: 225 lb.
- Repetitions: 5.
- Using Epley, estimated 1RM = 225 x (1 + 5 / 30) = 262.5 lb.
Kilogram example
- Weight lifted: 100 kg.
- Repetitions: 3.
- Using Epley, estimated 1RM = 110 kg.
Training percentage example
- If estimated 1RM is 200 lb, 80% is 160 lb.
- Training percentages help plan submaximal working sets.
Common mistakes
Treating an estimate as a guarantee
One-rep max formulas estimate strength and can be wrong for individual lifters.
Using very high rep sets
Higher rep counts tend to make 1RM estimates less reliable.
Ignoring technique
Only use reps completed with consistent range, control, and form.
Testing maxes too aggressively
Use conservative loading, proper warmups, and qualified supervision.
FAQs
What does this Strength Calculator do?
What is one-rep max?
Which formula should I use?
Is the result exact?
Can I use kilograms?
Can I use pounds?
Why limit reps to 30?
What is the Epley formula?
What is the Brzycki formula?
What is the Lombardi formula?
What is the O'Conner formula?
What are training percentages?
Can this calculator replace coaching?
Should beginners test one-rep max?
Why do different formulas give different results?
References
Related calculators
Last updated and version history
Last updated: 2026-07-10
- 1.0.0 (2026-07-10): Initial max bench calculator page using the verified strength engine.