One-Rep Max Calculator
Enter the weight you lifted and how many reps you completed to estimate your 1RM and generate a full training table.
The Formulas Explained
Two widely-used formulas estimate 1RM from a submaximal lift:
For example, a 225 lb bench press for 5 reps: Epley = 225 × (1 + 0.0333 × 5) = 262 lbs. Brzycki = 225 × 36 / 32 = 253 lbs.
Average Strength Standards (Barbell Back Squat)
| Level | Men (1RM) | Women (1RM) |
|---|---|---|
| Beginner | ≈ 135 lbs | ≈ 65 lbs |
| Novice | ≈ 205 lbs | ≈ 105 lbs |
| Intermediate | ≈ 270 lbs | ≈ 145 lbs |
| Advanced | ≈ 345 lbs | ≈ 190 lbs |
| Elite | ≈ 435+ lbs | ≈ 245+ lbs |
Standards based on a 198 lb / 90 kg male and 148 lb / 67 kg female. Source: Symmetric Strength / ExRx.net.
Frequently Asked Questions
What is a one-rep max (1RM)?
A one-rep max is the maximum weight you can lift for a single complete repetition with proper form for a given exercise. It is the gold standard for measuring absolute strength and is used to program training loads — for example, performing 4 sets of 6 reps at 80% of 1RM.
Which formula is more accurate — Epley or Brzycki?
Both are widely used and produce similar results at low rep counts. The Epley formula tends to overestimate at very high reps (15+), while Brzycki becomes unreliable above ~10 reps. For best accuracy, test with a weight you can lift for 1–5 reps. The average of both formulas is often used in practice.
Is it safe to test my actual 1RM?
Testing true 1RM carries injury risk, especially for beginners and in exercises with complex movement patterns (e.g., Olympic lifts). Using a calculator from a 3–5 rep effort is a safer and often more practical approach. If you do test your 1RM, use a spotter, warm up thoroughly, and don't attempt a true max more than a few times per year.
How do I use 1RM percentages for training?
Common strength training protocols use percentage-based loading: 90–95% for max strength (1–3 reps), 80–85% for hypertrophy strength (4–6 reps), 70–75% for hypertrophy volume (8–12 reps), and 50–65% for power or endurance work. Periodization programs like 5/3/1, Westside, and linear progression all use 1RM-based percentages.