One Rep Max Calculator

Estimate your one-rep max from a submaximal set, with training loads from 50% to 95%.

Estimated 1RM (Epley)

233.33


Estimated 1RM (Brzycki)

225

Most accurate under 10 reps

Training loads from your 1RM

% of 1RMWeightTypical reps
95%2202
90%2104
85%2006
80%1858
75%17510
70%16512
65%15015
60%14017
55%13020
50%11524

You don't need to grind a true one-rep max to program training percentages. A hard set of 3-8 reps predicts it accurately. This calculator uses the Epley and Brzycki formulas to estimate your max from a submaximal lift - the two agree at low reps and diverge past ~10 reps, which is why both are shown. Results are in whatever unit you lift in (pounds or kilograms), and training loads are rounded to the nearest 5 for plate math.

Epley: 1RM = w × (1 + reps ÷ 30); Brzycki: 1RM = w × 36 ÷ (37 − reps)

Examples

A hard set of 200 x 5 estimates to 233.33 lbs (Epley) or 225 lbs (Brzycki) - both reasonable predictions for a true max.

At 95% of that estimated max, you'd load 220 lbs for a double, a standard strength-training rep range.

FAQ

How accurate are one-rep max formulas?

These formulas are empirical estimates trained on lifting data. They're most accurate for reps in the 3-8 range; accuracy decreases beyond 10 reps. Always treat predictions as guides, not absolutes.

Epley or Brzycki - which should I use?

Both are defensible. Epley typically predicts slightly higher maxes at high rep counts, while Brzycki is more conservative. Use whichever matches your experience, or split the difference.

What percentage of my max should I train at?

Strength work is typically 85-95% (2-5 reps); hypertrophy is 65-85% (6-12 reps); endurance is 50-70% (15-20 reps). The table above shows typical rep ranges for each load percentage.

This calculator provides estimates for educational purposes only and is not medical advice.