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Deadlift one rep max calculator

Enter your deadlift weight and rep count to estimate your one rep max and see a full training percentage table. Works for conventional, sumo, and Romanian deadlifts, the formula applies to any variation where you are lifting a maximal load.

Exercise

How it works

Two formulas are used and averaged. The Epley formula (1985): 1RM = weight × (1 + 0.0333 × reps). The Brzycki formula (1993): 1RM = weight × 36 / (37 − reps). Both assume a near-maximal set of 1–12 reps. The percentage table divides the estimated 1RM by each percentage to give your working weight for that intensity zone. All arithmetic runs locally in your browser.

Processing runs in your browser

All calculations happen locally using pure JavaScript. Our servers are not involved at any point.

Technical specification

The Epley formula was published by Boyd Epley (1985) and remains the most widely used 1RM estimator in strength and conditioning. The Brzycki formula was published by Matt Brzycki in Strength & Conditioning Journal (1993). Both are population-average models with a standard error of approximately ±3–5 kg on sets of 3–5 reps. Accuracy decreases above 10 reps as aerobic capacity increasingly influences performance.

Epley formula
weight × (1 + 0.0333 × reps)
Brzycki formula
weight × 36 / (37 − reps)
Valid rep range
1–12 reps (accuracy decreases above 8)
Browser API
Pure JavaScript arithmetic. No library

Related operations

For estimating daily energy needs for a training plan, try the calorie calculator. To track fat-free mass between training blocks, use the lean body mass calculator. For setting cardio targets alongside strength work, see the heart rate calculator.

Frequently asked questions

Why does the deadlift 1RM sometimes feel different from the calculated value?
The deadlift has a high demand on grip, posterior chain fatigue, and breathing mechanics at maximal loads. These factors mean some lifters perform better at lower rep ranges than the formula predicts, and vice versa.
What is a good deadlift 1RM for my bodyweight?
General strength standards: 1.0× bodyweight is beginner, 1.5× is intermediate, 2.0× is advanced, and 2.5×+ is elite. These vary by sex, age, and training age.
Can I use this for trap bar or Romanian deadlift?
Yes. The formula is load-agnostic, enter the weight and reps for any deadlift variation and the estimated 1RM will apply to that specific movement.
Is my data sent to a server?
All calculations are pure JavaScript running in your browser. Our servers are not involved at any point.

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