One-Rep Max Calculator 2025: Know Your True Strength
Your one-rep max (1RM) is the maximum weight you can lift once with proper form. Testing it directly is risky, so our 1RM Calculator estimates it safely using Epley, Brzycki, and Lander formulas based on your multi-rep performance. Perfect for bench press, squat, deadlift, and more, this tool helps you plan workouts and track progress.
What Is One-Rep Max (1RM)?
1RM is the gold standard for measuring strength. It’s used to:
- Set training percentages (e.g., 70% of 1RM for hypertrophy)
- Track strength gains over time
- Compare against strength standards
1RM Formulas Explained
Epley: 1RM = Weight × (1 + Reps/30)
Most popular, good for 1–10 reps.
Brzycki: 1RM = Weight × (36 / (37 − Reps))
Slightly conservative, best for 4–12 reps.
Lander: 1RM = (100 × Weight) / (101.3 − 2.67123 × Reps)
Similar to Epley, slightly different curve.
Average: Combines all three for balanced estimate.
How to Use This Calculator
- Enter weight lifted (kg or lbs).
- Input reps performed (1–12).
- Select exercise for strength comparison.
- Choose formula (Epley recommended).
- Click "Calculate" to see 1RM and strength level.
Strength Standards (Bench Press, Male, 80kg)
| Level | 1RM (kg) | Description |
|---|---|---|
| Beginner | 60 | New to lifting |
| Novice | 80 | 6–12 months training |
| Intermediate | 100 | 1–2 years consistent |
| Advanced | 130 | 3–5 years dedicated |
| Elite | 160 | Top 1% lifters |
Example Calculation
Bench Press, 100 kg × 5 reps, Epley:
1RM = 100 × (1 + 5/30) = 116.7 kg
Strength Level: Intermediate (for 80kg male).
Training Percentages
Use your 1RM to set weights:
- Endurance: 50–70% (12–20 reps)
- Hypertrophy: 70–85% (6–12 reps)
- Strength: 85–100% (1–5 reps)
Common Mistakes
- Using high reps (>12) — less accurate
- Poor form during test lifts
- Not warming up properly
- Ignoring bodyweight differences in standards
Pro Tips
- Test 3–6 reps for best accuracy
- Retest every 4–8 weeks
- Use with Calorie Burn Calculator for nutrition
- Follow a program (e.g., 5/3/1, StrongLifts)
FAQs
Is 1RM testing safe? Estimating via calculator is safer than maxing out.
How often should I test? Every 4–8 weeks, or after a strength cycle.
Do women use the same standards? No — women’s 1RM is typically 60–80% of men’s for same bodyweight.
Conclusion
Our One-Rep Max Calculator takes the guesswork out of strength training. Use it to find your 1RM, set smart training loads, and track your progress like a pro. Pair with TDEE for nutrition planning.
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