How much can you lift for one rep? This 1RM calculator estimates your one-rep max from the weight you lifted and the reps you finished. Enter 100 kg for 5 reps and the Epley formula gives about 117 kg. The page also shows six more formulas and your training weights at 67–100% of your max.
Estimated 1RM from 7 formulas (Epley 1985, Brzycki 1993, Lander 1985, Lombardi 1989, O'Conner 1989, Mayhew 1992, Wathen 1994).
These are estimates for general information only, not medical advice.
find your max, then set weights as a share of it.
retest the same lift and compare your max over time.
estimate your max from a hard set without lifting it.
Epley, Brzycki and five more, side by side.
your weights at 67–100% of your max.
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Epley (1985): 1RM = w × (1 + r ÷ 30)
Brzycki (1993): 1RM = w × 36 ÷ (37 − r)
Lander (1985): 1RM = 100w ÷ (101.3 − 2.67123 × r)
Lombardi (1989): 1RM = w × r^0.10
O'Conner (1989): 1RM = w × (1 + 0.025 × r)
Mayhew et al. (1992): 1RM = 100w ÷ (52.2 + 41.9 × e^(−0.055r))
Wathen (1994): 1RM = 100w ÷ (48.8 + 53.8 × e^(−0.075r))
w is the weight you lifted.
r is the reps you finished.
Estimates are most reliable from 2–10 reps.
All seven formulas disagree by a few percent.
That spread is normal.
Do not test a true one-rep max alone.
Use a spotter and safety bars.
Epley B (1985), Poundage Chart. Brzycki M (1993), Strength testing — predicting a one-rep max from reps-to-fatigue.
Lombardi VP (1989), Beginning Weight Training. O'Conner B, Simmons J, O'Shea P (1989), Weight Training Today.
Mayhew JL et al. (1992), bench press strength prediction. Lander J (1985), maximum based on reps.
Wathen D (1994), Load assignment, in Essentials of Strength Training and Conditioning (NSCA).
How much can you lift for one rep? This 1RM calculator estimates your one-rep max from the weight you lifted and the reps you finished. Enter 100 kg for 5 reps and the Epley formula gives about 117 kg. The page also shows six more formulas and your training weights at 67–100% of your max.
Epley is the most common default. Brzycki runs a little lower. Check the full table and use the middle of the range.
Use a hard set of 2–10 reps taken close to failure. Sets above 10 reps give rough estimates only.
Each formula was fitted to a different group of lifters. A spread of a few percent is normal, not an error.
A true max test is hard on your body and carries injury risk. Use a spotter, warm up well, and use safety bars. This calculator estimates your max so you can skip the test.
WorkoutPlanMaker is built by an independent maker, not a clinic. Calculations use published formulas (Mifflin-St Jeor 1990 for BMR, U.S. Navy method for body fat, WHO ranges for BMI). Results are estimates for general information only, not medical advice. Talk to a healthcare professional before starting a new diet or exercise program.
