StrengthCalc

Bench Press 1RM Calculator

Estimate your bench press max from a set you have already done — no max attempt needed. Enter the weight and the clean reps you completed.

Last reviewed · How we calculate

Bench press 1RM calculator

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How to estimate your bench press max

Bench a weight you can lift for 3–6 clean reps, stop when the next rep would be a grind or a miss, and enter the weight and reps above. The calculator returns six formula estimates and their average — for example, 185 lb × 5 estimates a bench max of roughly 208–220 lb.

The bench press is the lift most 1RM equations were built around. Mayhew’s formula was fitted to bench-press data from college men and women, and later studies that compared equations against tested maxes almost always included the bench (LeSuer et al., 1997; Reynolds et al., 2006). That makes it the lift where formula estimates have been checked most.

What counts as a clean bench rep

  • Touch the chest every rep. Stopping a few inches short shortens the range of motion and inflates the estimate.
  • No bouncing. Bouncing the bar off the chest adds momentum the formulas do not account for. A brief touch is fine; a pause is stricter still.
  • Hips stay on the bench. Lifting the hips changes the pressing angle and makes reps easier than they should be.
  • Same grip and setup as your heavy sets. A narrower or wider grip than usual will give a different number.

If you compete or test with a paused bench, estimate from paused reps too. Touch-and-go reps are usually stronger than paused ones, so an estimate from touch-and-go sets can read high for a paused max.

Bench press safety for heavy sets

  • Use a spotter who knows when to take the bar, or bench inside a rack with safety arms set just below chest height.
  • Use a full grip with the thumb wrapped around the bar — a thumbless grip lets the bar roll out of your hands.
  • For a true max attempt, follow a structured protocol: see how to test your 1RM safely.

Using your bench estimate in training

Bench strength usually moves in small steps, so percentages matter. A 5% change on a 225 lb bench is only about 11 lb. The percentage calculatorrounds every working weight down to a loadable 5 lb or 2.5 kg step, and the plate loader in your results shows exactly what goes on each side.

Worked example

Worked example: Bench press, 185 lb × 5 reps
FormulaEstimated 1RM
Epley215.8 lb
Brzycki208.1 lb
Lombardi217.3 lb
Mayhew220.2 lb
O'Conner208.1 lb
Wathan215.7 lb
Average Estimate214.2 lb

The six formulas put this set between 208.1 and 220.2 lb— a 5.8% spread — with an Average Estimate of 214.2 lb.

Use the range, not just the middle number: plan training from the Average Estimate or lower, and treat the top of the range as optimistic.

Sources

  1. Mayhew, J. L., Ball, T. E., Arnold, M. D., & Bowen, J. C. (1992). Relative muscular endurance performance as a predictor of bench press strength in college men and women. Journal of Applied Sport Science Research, 6(4), 200–206.
  2. LeSuer, D. A., McCormick, J. H., Mayhew, J. L., Wasserstein, R. L., & Arnold, M. D. (1997). The accuracy of prediction equations for estimating 1-RM performance in the bench press, squat, and deadlift. Journal of Strength and Conditioning Research, 11(4), 211–213.
  3. Reynolds, J. M., Gordon, T. J., & Robergs, R. A. (2006). Prediction of one repetition maximum strength from multiple repetition maximum testing and anthropometry. Journal of Strength and Conditioning Research, 20(3), 584–592. Link
  4. Human Performance Resources by CHAMP (HPRC), Uniformed Services University. What is a one-rep max? Link