Fitness & Health

One Rep Max Calculator

Estimate one-rep max and a practical training max.

Inputs

Adjust the assumptions to match your scenario. Results update instantly.

Weight liftedWorking weight used for the set that you completed.RepetitionsNumber of repetitions completed with the working weight.Training maxPercentage of estimated one-rep max used for a training max.

Results

Primary outputs and comparison insights are built from the current inputs.

Estimated 1RM

116.67

Estimated one-rep max based on the working set.

Training max

105

Conservative training max based on the selected percentage.

Rep set load

85.71%

Working weight shown as a percentage of the estimated one-rep max.

How this calculator works

The One Rep Max Calculator estimates your one-rep max from a working set and also gives you a practical training max for programming. Enter weight lifted, repetitions, and training max to estimate estimated 1rm, training max, and rep set load. The calculator updates instantly and adds a comparison table plus chart so you can test the sensitivity of the result before you use it in a decision.

Quick guide

Jump straight to the section you need, then return to the calculator.

Inputs Outputs Assumptions Tips Formulas Examples Reference table Visual breakdown References

Inputs

Working weight used for the set that you completed.
Number of repetitions completed with the working weight.
Percentage of estimated one-rep max used for a training max.

Outputs

Estimated one-rep max based on the working set.
Conservative training max based on the selected percentage.
Working weight shown as a percentage of the estimated one-rep max.

Assumptions

The estimate uses the Epley-style rep formula.
The working set is performed with good technique and near-max intent.

Tips

Use training max for programming if you want a more sustainable starting number.
Do not chase exactness from very high-rep sets or sloppy reps.

Formula guide

Use these formulas to audit the output or explain it to someone else.

2 formulas

Estimated 1RM = Weight × (1 + Reps ÷ 30)

Training Max = Estimated 1RM × Training Max %

Usage examples

Review a ready-made scenario, copy it, then tweak inputs to match your case.

Example

3 inputs3 outputs

Bench press estimate

Inputs

Example input Weight lifted: 85
Example input Repetitions: 6
Example input Training max: 90%

Outputs

Example result Estimated 1RM: 102
Example result Training max: 91.8
Example result Rep set load: 83.33%

Estimated 1RM formulas are most useful for planning and trend tracking rather than for declaring a perfect absolute max.

Estimated 1RM by reps

5 of 5 rows

Repetitions	Estimated 1RM	Training max
3	110	99
4	113.33	102
5	116.67	105
6	120	108
7	123.33	111

Rep-based 1RM formulas get less reliable as reps get high or technique breaks down, so stay in a realistic rep range.

Strength estimate by rep count

Highest: 7 (123.33)Lowest: 3 (110)

Sort

RepetitionsEstimated 1RM

Focus point

110

Position

#1 of 5

Original order

Share of total

18.86%

Total: 583.33

PositiveNegative

Rep-based 1RM formulas get less reliable as reps get high or technique breaks down, so stay in a realistic rep range.

References

Common one-rep max estimation formulas
Strength training programming with training maxes

FAQ

Common questions

What does the One Rep Max Calculator do?

What inputs do I need?

Typical inputs include Working weight used for the set that you completed., Number of repetitions completed with the working weight., Percentage of estimated one-rep max used for a training max..

How are the results calculated?

We follow the formulas and assumptions outlined in the "How this calculator works" section. You will see outputs like Estimated one-rep max based on the working set., Conservative training max based on the selected percentage., Working weight shown as a percentage of the estimated one-rep max..