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kg
The weight you actually lifted for all reps
Enter weight lifted (1–500 kg or lbs).
reps
Best accuracy: 1–10 reps. Above 15 reps reduces accuracy.
Enter reps between 1 and 30.
kg
Optional — used to show strength-to-weight standards
Estimated 1 Rep Max
0 kg
Based on Epley formula
⚠️ Disclaimer: 1RM calculators are estimates within approximately 5-10% for 1-10 rep sets. Accuracy decreases with reps above 10. Never attempt a true 1RM without proper warm-up, spotters, and safety equipment. These results are for training planning purposes only and do not constitute medical or fitness advice.
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Sources & Methodology
All 7 formulas sourced from peer-reviewed publications in the Journal of Strength and Conditioning Research. Strength standards from Symmetric Strength and NSCA training guidelines.
LeSuer DA, McCormick JH, Mayhew JL, et al. (1997). The accuracy of prediction equations for estimating 1-RM performance in the bench press. Journal of Strength and Conditioning Research, 11(4), 211-213.
Comparative validation study of multiple 1RM prediction equations including Epley, Brzycki, Lombardi, Mayhew, O'Conner, Wathan, and Lander formulas. This is the primary reference for the 7 formulas used in this calculator. Found Epley and Brzycki to be most accurate for the 2-10 rep range.
Mayhew JL, Ball TE, Arnold MD, Bowen JC. (1992). Relative muscular endurance performance as a predictor of bench press strength in college men and women. Journal of Applied Sport Science Research, 6(4), 200-206.
Original publication introducing the Mayhew et al. formula: 1RM = 100 x Weight / (52.2 + 41.9 x e^(-0.055 x Reps)). Validated for use with bench press prediction from submaximal efforts. Used in this calculator as one of 7 available formula options.
🧮 1RM Prediction Formulas — All 7 (Verified)
Epley (1985): 1RM = Weight x (1 + Reps / 30)
Brzycki (1993): 1RM = Weight x 36 / (37 - Reps)
Lombardi (1989): 1RM = Weight x Reps^0.10
Mayhew (1992): 1RM = 100 x W / (52.2 + 41.9 x e^(-0.055 x R))
O'Conner (1989): 1RM = Weight x (1 + 0.025 x Reps)
Wathan (1994): 1RM = 100 x W / (48.8 + 53.8 x e^(-0.075 x R))
Lander (1985): 1RM = 100 x W / (101.3 - 2.67123 x R)
For reps = 1, all formulas return exact weight. Best accuracy: Epley and Brzycki for 2-10 reps (LeSuer et al. 1997). Accuracy decreases with reps above 10.
✓ All formulas verified against original publications — Last reviewed April 2026
Bench Press Calculator — 1RM, Training Percentages & Strength Standards
The bench press is the most popular upper body strength exercise and the most commonly tested lift in gym settings worldwide. Knowing your estimated one-rep maximum (1RM) unlocks your ability to structure training percentages, track progress over time, and compare your performance to established strength standards without the injury risk of true maximal attempts.
The Epley and Brzycki Formulas — Which Is Most Accurate?
Two formulas dominate 1RM prediction research: Epley (1985) and Brzycki (1993). The landmark comparison study by LeSuer et al. (1997) in the Journal of Strength and Conditioning Research tested all seven major prediction equations and found Epley and Brzycki to be consistently most accurate for the bench press in the 2-10 rep range, with errors typically under 5%.
For very low reps (1-3), the difference between formulas is minimal because actual performance approximates true 1RM directly. For higher rep sets (8-12), Brzycki tends to give slightly more conservative (lower) estimates which research suggests are more realistic. Above 15 reps, all formulas become increasingly inaccurate because muscular endurance and cardiovascular factors begin to limit performance rather than maximal strength.
Bench Press Strength Standards by Bodyweight
| Level | Males (ratio to BW) | Females (ratio to BW) | Example (80 kg male) |
|---|---|---|---|
| Beginner | 0.5x BW | 0.35x BW | 40 kg |
| Novice | 0.75x BW | 0.50x BW | 60 kg |
| Intermediate | 1.0x BW | 0.65x BW | 80 kg |
| Advanced | 1.25x BW | 0.80x BW | 100 kg |
| Elite | 1.50x BW | 1.00x BW | 120 kg |
| World Class | 2.0x+ BW | 1.35x+ BW | 160 kg+ |
How to Use Training Percentages for Bench Press Programming
Training percentages derived from your 1RM are the foundation of structured programming. Different percentage zones produce different physiological adaptations:
- 50-65% 1RM (Speed/technique): 15-20 reps. Builds movement quality, speed-strength, and serves as warm-up range. Used in dynamic effort training.
- 65-75% 1RM (Hypertrophy): 10-15 reps. Primary range for muscle size development. Sufficient mechanical tension and metabolic stress for growth.
- 75-85% 1RM (Strength-hypertrophy): 6-10 reps. Crossover zone for both strength and size gains. Most general program work sets fall here (Starting Strength, 5/3/1).
- 85-95% 1RM (Strength): 2-5 reps. High neural demand, significant strength gains with proper recovery between sessions.
- 95-100% 1RM (Peaking): 1-2 reps. Competition preparation, personal record attempts, peak neural activation.
The 1RM test vs calculated 1RM: For most training purposes, a calculated 1RM from a 3-5 rep set is safer and nearly as accurate as a true 1RM test. True maximal lifts carry injury risk from momentary form breakdown, and the nervous system cost of a true 1RM can affect training for 3-5 days. Use a 3-5 rep max performance every 4-6 weeks as your testing method, and calculate 1RM from that effort. This approach is standard practice in evidence-based strength programming.
Frequently Asked Questions
The Epley formula: 1RM = Weight x (1 + Reps/30). Example: 100 kg for 5 reps = 100 x (1 + 5/30) = 100 x 1.167 = 116.7 kg. The Brzycki formula: 1RM = Weight x 36 / (37 - Reps). For 100 kg x 5 reps = 100 x 36 / 32 = 112.5 kg. Both are within 5% for 2-10 rep sets per LeSuer et al. (1997). Use the calculator above to get results from all 7 validated formulas simultaneously.
Strength standards for men: Beginner = 0.5x bodyweight. Novice = 0.75x BW. Intermediate = 1.0x BW (bodyweight bench). Advanced = 1.25x BW. Elite = 1.5x BW. World class = 2.0x+ BW. For women, multiply by approximately 0.65-0.70. A bodyweight bench press is the most common intermediate milestone. Enter your bodyweight in the calculator above to see exactly which level your 1RM falls into.
Within 5-10% for 1-10 rep sets (LeSuer et al. 1997 validation study). Accuracy decreases with higher reps: 10-rep max estimates have 8-12% error; 15-rep max estimates can have 15-20% error. Best accuracy comes from 3-6 rep maximum efforts where fatigue effects are minimal. The calculator is unsuitable for estimating from 20+ rep endurance sets.
Epley formula (Boyd Epley, University of Nebraska, 1985): 1RM = Weight x (1 + Reps / 30). It is the most widely used 1RM prediction equation in strength and conditioning. One of 7 formulas available in our calculator. Most common in fitness apps, strength trackers, and academic research. Tends to slightly overestimate for high rep sets (above 15).
50-65% = Speed/technique work (15-20 reps). 65-75% = Hypertrophy (10-15 reps). 75-85% = Strength-hypertrophy hybrid (6-10 reps, most common training zone). 85-95% = Strength focus (2-5 reps). 95-100% = Peaking/competition prep (1-2 reps). The calculator generates your full percentage table from 50% to 100% so you can load any set without manual calculation.
Primary: Pectoralis major (chest). Secondary: Anterior deltoid (front shoulder), triceps brachii. Stabilizers: Rotator cuff, serratus anterior, rhomboids, mid-trapezius. Grip width affects emphasis: wider grip increases pectoral recruitment; narrower grip shifts load to triceps. Incline press targets upper chest and anterior delts more; decline press hits lower pecs.
Limit true 1RM testing to 3-4 times per year, typically at the end of a training cycle. Instead, use 3-5 rep max sets every 4-6 weeks and calculate 1RM using this tool. Frequent true maximal testing is hard on the nervous system and joints, and increases injury risk. Calculated 1RM from heavy submaximal sets gives reliable progress tracking without the fatigue cost.
The 225-lb (approximately 102 kg) rep test is used at the NFL Scouting Combine. Players perform maximum reps at that weight. Elite results: 30+ reps exceptional. Offensive linemen average 25-30 reps. Skill positions (WR, CB) average 10-20 reps. World record: Justin Ernest, 51 reps (2000). Enter 225 lbs and your estimated reps in our calculator to find your equivalent 1RM for comparison.
Evidence-based methods: 1) Bench 2-3 times per week. 2) Strengthen supporting muscles: triceps (close-grip bench, skull crushers), upper back (rows, face pulls — prevents shoulder impingement). 3) Improve technique: scapular retraction and depression, leg drive, slight arch in upper back. 4) Periodize intensity. 5) Eat adequate protein (1.6-2.2g/kg BW). Most intermediates can add 20-40 lbs over 3-6 months of focused work.
Raw bench press uses minimal equipment (belt, optionally wrist wraps). Equipped bench press uses a bench shirt — a tight, elastic garment that stores energy during the descent and adds 30-100+ lbs to the lift. World equipped records significantly exceed raw records. All standards in this calculator and most gym programs use raw standards. USAPL and IPF maintain separate raw and equipped competition divisions.
Raw bench press world record: Jimmy Kolb, 355 kg (783 lbs), IPF World Championship. Equipped world record: Over 500 kg (1,102+ lbs) in multiply powerlifting federations. These are achieved by elite powerlifters under competition conditions with years of specialized training. The all-time heaviest confirmed raw bench press in competition exceeds 700 lbs.
Standard protocol: Empty bar x 10-15. Then 40-50% of working weight x 8. Then 60-65% x 5. Then 75-80% x 3. Then 90% x 1. Then working sets. Adequate warm-up reduces injury risk and typically allows slightly better performance on working sets. Total time: 10-15 minutes. Use the training percentage table from our calculator to identify your exact warm-up weights.
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