Where does the %1RM-to-reps table come from?

It is the NSCA/Baechle "Essentials of Strength Training and Conditioning" reference table, widely cited in resistance-training literature since the 1990s.

Why does my squat give different rep ranges than my bench at the same %1RM?

Larger compound lifts (squat, deadlift) usually allow 1–2 more reps at the same percentage than smaller lifts (bench, overhead press). Use the table as a starting point and adjust per exercise.

Should I always lift to failure?

No. Most evidence-based programs leave 1–3 reps in reserve on most sets. Reps-to-failure mode here is for occasional benchmark sets, not every workout.

How accurate is the Epley reverse 1RM?

Within about ±5% for sets of 1–6 reps. Past 10 reps, endurance limits the set more than strength does, and the estimate becomes less reliable.

Can I use this table for women, beginners, or older lifters?

Yes — the percentages are remarkably consistent across populations for compound barbell lifts. Beginners may see more variance because skill acquisition shifts week to week.

Workout Reps Calculator

Convert between %1RM, working weight, and reps using NSCA and Epley reverse 1RM.

Written by Golam Rabbani, Founder & Lead Engineer

This interactive tool requires JavaScript. Read the formula and worked example below; you can compute the result by hand.

How to use this workout reps calculator

Pick a mode: "Reps & weight from %1RM" (NSCA training table) or "Estimate 1RM from reps-to-failure" (Epley reverse).
Choose kg or lb. Switching converts any value already entered.
For NSCA mode, enter your 1RM. For Epley mode, enter the weight you lifted and how many reps you reached failure at.
Click Calculate to see the rep-to-percent table or the reverse 1RM estimate.
Copy the table for your training log or Reset to switch modes.

About this workout reps calculator

The Workout Reps Calculator converts between %1RM, working weight, and reps using the NSCA/Baechle reference table: 100%/1 rep, 95%/2, 93%/3, 90%/4, 87%/5, 85%/6, 83%/7, 80%/8, 77%/9, 75%/10, 70%/11, 67%/12, 65%/15. In Epley reverse mode it computes 1RM = weight × (1 + reps / 30) and tells you what percentage of that 1RM your set represented. As a worked example, with a 100 kg bench-press 1RM, the calculator says 85% (≈ 6 reps) is 85 kg and 75% (≈ 10 reps) is 75 kg — the standard NSCA hypertrophy and strength ranges. In Epley mode, 70 kg × 6 reps to failure estimates a 84 kg 1RM, meaning your set was 83% of 1RM. The %1RM ↔ reps mapping is a population average; individual rep maxes shift by 1–2 reps depending on muscle fiber type, exercise selection, and training history. This tool is for general fitness education and is not medical advice — consult a qualified strength professional before training to failure, especially with prior injuries.

FAQ

Where does the %1RM-to-reps table come from?: It is the NSCA/Baechle "Essentials of Strength Training and Conditioning" reference table, widely cited in resistance-training literature since the 1990s.
Why does my squat give different rep ranges than my bench at the same %1RM?: Larger compound lifts (squat, deadlift) usually allow 1–2 more reps at the same percentage than smaller lifts (bench, overhead press). Use the table as a starting point and adjust per exercise.
Should I always lift to failure?: No. Most evidence-based programs leave 1–3 reps in reserve on most sets. Reps-to-failure mode here is for occasional benchmark sets, not every workout.
How accurate is the Epley reverse 1RM?: Within about ±5% for sets of 1–6 reps. Past 10 reps, endurance limits the set more than strength does, and the estimate becomes less reliable.
Can I use this table for women, beginners, or older lifters?: Yes — the percentages are remarkably consistent across populations for compound barbell lifts. Beginners may see more variance because skill acquisition shifts week to week.