Free Tool · Strength Training
Progressive Overload Calculator
Enter every set from your last workout. We estimate your 1RM with Epley's formula and the RPE chart method, then generate your next session with precise weights, reps, and RPE targets.
Example: Set 1: 175 lbs × 8 reps, Set 2: 185 lbs × 6 reps, Set 3: 180 lbs × 7 reps @ RIR 2 on the last set.
How this works
Enter every set from your workout. We calculate 1RM for each set:
- All sets: Epley's formula = weight × (1 + reps / 30). Does not use RIR or RPE.
- Last set (optional): If RIR is provided, uses the RPE chart instead of Epley's.
- Result: The highest 1RM across all sets is used for recommendations.
| Set | Weight (lbs) | Reps | RIR | |
|---|---|---|---|---|
| 1 | · | |||
| 2 | · | |||
| 3 |
How it works
Two estimates, highest wins
Every set you log is converted into a 1RM estimate using Epley's formula: 1RM = weight × (1 + reps / 30). If you provide RIR on your final set, we also calculate an RPE-based 1RM using a standard RPE-to-percent-1RM lookup table.
We take the highest of these estimates and treat it as your working 1RM. That figure is multiplied by your goal-appropriate percentage to prescribe the weight, reps, RPE, and sets for your next session. Rounding drops to the nearest 2.5 pound increment for loadable gym plates.
This combination of Epley plus RPE is more reliable than either method alone. Epley handles most submaximal sets well but ignores proximity to failure; RPE captures proximity to failure but breaks down at high rep ranges. Taking the higher estimate prevents regression when either signal under-reports your capacity.
Training zones
Pick the zone that fits your goal
Strength
85 to 100% 1RM
1 to 5 reps. Neural adaptations and maximal force production. Long rest.
Hypertrophy
65 to 85% 1RM
6 to 12 reps. Muscle growth and work capacity. Moderate rest.
Endurance
50 to 65% 1RM
12 to 20+ reps. Muscular stamina and metabolic conditioning.
Frequently asked questions
Questions we hear a lot
One-Rep Max (1RM) is the maximum weight you can lift for a single repetition with proper form. Most lifters never test a true 1RM. Instead, they estimate it from submaximal sets. This calculator uses both Epley's formula and the RPE chart method to generate two independent estimates, then uses the higher value for progressive overload programming.
Epley's formula is accurate within about 3 percent for sets in the 2 to 10 rep range. Accuracy drops for higher rep ranges (15+) and for sets taken short of failure. For best results, enter sets that are within 2 reps of failure (RIR 0 to 2) and your baseline 1RM will be reliable week over week.
Reps In Reserve (RIR) is how many more reps you could have done before failing. RIR 2 means you stopped with two reps left in the tank. RIR captures effort more precisely than just weight and reps, which is why we layer in an RPE-based 1RM estimate for your last set when you log it.
Add weight when you hit the top of your target rep range on every prescribed set with your target RIR. For hypertrophy goals (6 to 12 reps), expect to add 2.5 to 5 pounds per lift every one to two weeks in the first year of training. For strength (1 to 5 reps), progression is slower and more volume-sensitive.
Choose Strength for maximum force production at 1 to 5 reps per set at 85 to 100 percent of 1RM. Choose Hypertrophy for muscle size at 6 to 12 reps at 65 to 85 percent. Choose Endurance for muscular stamina at 12 to 20+ reps at 50 to 65 percent. Most general lifters should default to Hypertrophy.
Yes. The Sculpt AI progressive overload calculator is free and requires no account. The Sculpt AI app extends this with continuous programming that auto-adjusts every session based on how you actually performed.