Calculate Your One-Rep Max

Warm-up Working Max Effort PR Attempt

Your One-Rep Max Results

116.7
Intermediate

Training Max (90% of 1RM)

For Programming 105.0
Formula Used Epley
Accuracy Range ± 3-5%

Strength to Bodyweight Ratio

1.46x

Your 1RM is 1.46 times your body weight

Strength Standards (Male, 80kg)

Beginner 1.0x BW
Intermediate 1.5x BW
Advanced 2.0x BW
Elite 2.5x+ BW

Training Percentages Chart

5×5 Weight

87.5

3×3 Weight

99.0

10RM Estimate

88.3

Max Reps @70%

12-15

Next Cycle Goal

121.0

Weekly Volume

10-15 sets

Deload Every

6-8 weeks

Understanding One-Rep Maximum (1RM)

1RM is the maximum amount of weight you can lift for one repetition with proper form. It’s the gold standard for measuring absolute strength.

Why Calculate 1RM?

  • Training Prescription: Set appropriate weights for different rep ranges
  • Progress Tracking: Measure strength gains over time
  • Periodization: Structure training cycles effectively
  • Safety: Avoid attempting true 1RM too frequently
  • Goal Setting: Establish realistic strength targets
Rep Range % of 1RM Training Purpose
1-3 reps 90-100% Maximal strength, neural adaptation
4-6 reps 85-90% Strength, some hypertrophy
8-12 reps 67-85% Hypertrophy, muscle growth
12-15+ reps 60-67% Muscular endurance, conditioning
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Training Max Concept

Most programs use 90% of true 1RM for programming to account for daily fluctuations and ensure consistent progress.

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Strength Standards

Evaluate your strength relative to body weight. A 2x body weight squat is considered advanced for most lifters.

1RM Calculation Formulas

Different formulas provide slightly different estimates. The “Average” option combines multiple formulas for the most accurate prediction.

Formula Equation Best For Accuracy
Epley 1RM = w × (1 + r/30) General use, most popular ± 2.5%
Brzycki 1RM = w × (36/(37 – r)) Lower rep ranges (1-10) ± 3%
Lander 1RM = (100 × w)/(101.3 – 2.67123 × r) Powerlifting specificity ± 3.5%
Wathan 1RM = (100 × w)/(48.8 + 53.8 × e^(-0.075 × r)) All rep ranges ± 2%
Lombardi 1RM = w × r^0.1 Higher rep ranges ± 4%
Mayhew 1RM = (100 × w)/(52.2 + 41.9 × e^(-0.055 × r)) College athletes ± 3%
O’Conner 1RM = w × (1 + 0.025 × r) Simple calculation ± 5%

Example Calculation (Epley Formula)

If you lift 100kg for 5 reps:

1RM = 100 × (1 + 5/30) = 100 × 1.1667 = 116.7kg

Your estimated one-rep maximum is 116.7kg.

1

Formula Accuracy

Formulas are most accurate with 3-8 reps. Beyond 10 reps, accuracy decreases significantly.

2

Individual Variation

Some lifters are better at high reps, others at singles. Use the formula that matches your strength curve.

3

When to Test

Actual 1RM testing should be done sparingly (every 8-12 weeks) and only with proper preparation and spotters.

Programming with 1RM

Program Type % of 1RM Sets × Reps Frequency
Strength Focus 85-95% 5×5, 6×3, 8×2 2-3×/week
Hypertrophy 67-85% 3×8-12, 4×10 1-2×/week
Power/Peaking 75-85% 8×2, 10×1 1-2×/week
Maintenance 70-80% 3×5, 2×8 1×/week

Sample 6-Week Strength Cycle

  • Week 1-2 (Accumulation): 5×5 @ 75% → 5×5 @ 80%
  • Week 3-4 (Intensification): 4×4 @ 82.5% → 4×4 @ 85%
  • Week 5 (Peaking): 3×3 @ 87.5% → 2×2 @ 90%
  • Week 6 (Deload): 3×5 @ 70%
  • Week 7 (Test): Work up to new 1RM
1

RPE-Based Training

Combine percentages with RPE (Rate of Perceived Exertion). If @75% feels like RPE 9, adjust weight down.

2

Auto-Regulation

Adjust weights based on daily readiness. Some days you’ll be stronger than others.

3

Exercise Variation

Use different variations (paused, tempo, deficit) at slightly lower percentages to build strength.

Powerlifting Total Calculator

Total = Squat 1RM + Bench 1RM + Deadlift 1RM

Example: 180kg + 120kg + 220kg = 520kg total

Wilks Score (Strength Relative to Bodyweight)

Formula: Score = Total × 500 / (a + b × BW + c × BW² + d × BW³ + e × BW⁴ + f × BW⁵)

400+ = Advanced | 300-399 = Intermediate | 200-299 = Beginner

Safety Tips for 1RM Testing

1

Proper Warm-up

Spend 15-20 minutes warming up with dynamic stretches, light sets, and progressively heavier weights.

2

Use Spotters

Always have competent spotters for bench press and squat. For deadlifts, use bumper plates.

3

Know Your Limits

Stop if you feel joint pain, sharp muscle pain, or if form breaks down significantly.

4

Proper Equipment

Use power rack safety pins, bench with safeties, proper footwear, and weightlifting belt if needed.

5

Listen to Your Body

Don’t test 1RM if you’re fatigued, sick, or recovering from injury. Postpone for another day.

6

Gradual Increases

Increase weight in small increments (2.5-5kg) and take adequate rest between attempts (3-5 minutes).

1RM Testing Protocol

  1. Week Before: Light training, focus on recovery
  2. Test Day: Full rest, good nutrition, optimal time of day
  3. Warm-up: 10× empty bar, 5× 50%, 3× 70%, 1× 80%, 1× 90%
  4. Attempts: 95% (opener), 100% (second), 102.5% (third if feeling good)
  5. After: Light cooldown, proper nutrition, 2-3 days light training

Critical Safety Warning

1RM testing carries inherent risks. Always train with proper form, use appropriate equipment, and have qualified spotters. If you’re new to lifting, spend at least 6 months building a base before attempting 1RM testing. Consult with qualified strength coaches or trainers if unsure.