Bench Press 1RM (Epley)
Estimates one-rep max (1RM) bench press by Epley formula.
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Epley 1RM: estimating bench press max
The Epley formula (1985) is the 1RM estimator most people reach for: 1RM = weight · (1 + reps/30). Example: 80 kg × 5 reps → 80 · (1 + 5/30) = 80 · 1.167 ≈ 93.3 kg. Brzycki, for the same set, gives 80 · 36/(37 − 5) = 90 kg, so Epley runs a little higher in the 4-10 rep range. Count on it between 1-10 reps; past 12 reps every formula starts overshooting. Progression: by following your projected 1RM across mesocycles you can see strength go up without ever forcing a true max-out, which on the bench is both draining and risky.
Applications: percentage training and periodization
It drives percentage-based programming (5/3/1, Sheiko, Westside), where every load is written as a %1RM, and it underpins linear periodization mesocycles that work their way up from 70% to 95% of 1RM. Apps such as Bench Press Pro, Strong and Hevy default to Epley when projecting a max from your working sets. Powerlifters lean on that projected 1RM when they pick their opener and second attempt.
FAQ
Why Epley and not Brzycki? Both hold up well to 10 reps. Epley is the simpler equation and reads a bit higher; Brzycki stays more conservative once you pass 6 reps. Whichever you choose, stay with it so your numbers track cleanly.
Does it work for any exercise? It shines on the big compounds (bench, squat, deadlift). On isolation lifts like curls or lateral raises, technique and fatigue throw the estimate off.
How many reps should I use? Aim for 3-8 reps with clean form for the most reliable projection. A set taken close to failure estimates better than one you cut off well short.
How often should I re-test? Every 4-6 weeks works, or sooner if the prescribed percentages start feeling clearly too light or too heavy.
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The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.