Calculator Inputs
Example Data Table
| Lifter | Weight Lifted | Reps | RPE | Estimated 1RM | Unit |
|---|---|---|---|---|---|
| Athlete A | 70 | 8 | 9 | 89.7 | kg |
| Athlete B | 185 | 5 | 9.5 | 214.8 | lb |
| Athlete C | 82.5 | 3 | 10 | 90.8 | kg |
| Athlete D | 135 | 10 | 8.5 | 172.4 | lb |
Formula Used
Epley: 1RM = Weight × (1 + Effective Reps ÷ 30)
Brzycki: 1RM = Weight × 36 ÷ (37 − Effective Reps)
Lombardi: 1RM = Weight × Reps0.10
O'Conner: 1RM = Weight × (1 + 0.025 × Effective Reps)
Mayhew: 1RM = 100 × Weight ÷ (52.2 + 41.9 × e−0.055 × Effective Reps)
Wathan: 1RM = 100 × Weight ÷ (48.8 + 53.8 × e−0.075 × Effective Reps)
RPE adjustment: Effective Reps = Completed Reps + Reps in Reserve, where Reps in Reserve = 10 − RPE.
Using several formulas helps compare aggressive and conservative estimates. The average option smooths out outlier predictions and is useful for programming incline bench progressions.
How to Use This Calculator
- Enter the load you pressed on the incline bench.
- Input the repetitions completed with sound technique.
- Set your RPE to reflect effort honestly.
- Add bodyweight if you want strength ratio analysis.
- Choose your preferred prediction formula or the average.
- Adjust training max, rounding, bar weight, and plate size.
- Press the calculate button to view results above the form.
- Review the 1RM estimate, warm-ups, plate loads, and rep chart.
- Use CSV or PDF export for workout logs and coaching notes.
FAQs
1. What is an incline bench 1RM?
It is the maximum load you could likely press once on an incline bench with proper technique. This calculator estimates that value from a submaximal set.
2. Why use RPE in the estimate?
RPE adjusts the prediction for how close the set was to failure. A set of five at RPE 8 usually suggests more reserve than five at RPE 10.
3. Which formula should I choose?
Use the average option for balanced planning. If you prefer one method from prior testing, choose that formula and compare its output against your actual performance.
4. Are incline and flat bench 1RM values the same?
No. Most lifters press less on the incline bench because the shoulder angle changes leverage and increases upper chest and front delt demand.
5. What rep range gives the best estimate?
Sets from 1 to 10 reps usually work best. Lower reps often give tighter estimates, while high-rep fatigue can make predictions less precise.
6. What is training max?
Training max is a reduced percentage of your estimated 1RM, often 85% to 95%. It helps manage fatigue and improves programming consistency.
7. Can beginners use this calculator?
Yes. Beginners can use it to avoid frequent maximal attempts. Consistent technique and honest effort ratings improve the estimate over time.
8. Why do rounded loads matter?
Real gyms use fixed plate sizes, so exact calculated values are rarely loadable. Rounding converts theory into weights you can actually place on the bar.