Bench Press Max Calculator

The bench press is the lift most people mean when they ask what someone can lift. It is also the lift where a genuine max attempt costs the most if it goes wrong. Estimate instead: enter the weight and reps from a controlled set. Values are in kilograms — 185 lb goes in as 84 kg.

Worked example

185 lb (84 kg) for 5 clean reps:

• Epley: 84 × (1 + 5 ÷ 30) = 98.0 kg, about 216 lb
• Brzycki: 84 × 36 ÷ (37 − 5) = 94.5 kg, about 208 lb
• Average of the two: 96.3 kg, about 212 lb

An 8 lb spread between the two formulas at this rep count is normal, and it is smaller than the week-to-week noise in your own performance.

The lift the equations were actually built on

This matters more than it sounds. Almost every classic 1RM equation was derived from bench press data — Mayhew’s 2008 comparison of 14 formulas, one of the few that tested them against measured maxes, used the bench press in 103 college women before and after 12 weeks of training. So of all the lifts you might apply these formulas to, the bench is the one where they are closest to home, and even here the best equations matched the real max within 2.3 kg for only 58% of lifters.

Failing safely

Resistance training injuries concentrate in the shoulder, which accounts for somewhere between 10.5% and 50% of reported cases depending on the study. The bench press adds a specific mechanism: with the arms abducted and internally rotated under load, a fatigued or asymmetric rep is how pectoralis major ruptures happen. Before you take a set anywhere near failure:

• Use a spotter, or set the rack pins at chest height so a failed rep lands on steel.
• Keep your thumbs wrapped around the bar. The thumbless “suicide grip” has exactly one failure mode and it ends on your sternum.
• Stop the reference set one or two reps early. You are estimating the max, not testing it — the last grinding rep adds risk and almost nothing to the number.

The same set, other lifts

• Squat max calculator
• Deadlift max calculator
• Overhead press max calculator
• Bicep curl max calculator

Turn the estimate into working loads with the 1RM percentage chart, or read how the equations differ on the one rep max calculator. This content is informational and does not replace coaching or medical advice.