Estimate 1-Rep Max (Epley)

Excel Formulas › Fitness & Gym

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One-rep max (1RM) estimates the most you could lift once from a set you did for several reps. The Epley formula — weight × (1 + reps/30) — is the common standard.


Quick formula: 1RM from weight and reps (Epley):
=weight * (1 + reps / 30)
Weight times one plus reps over 30 estimates a single-rep maximum from a multi-rep set.

The example

185 lb for 5 reps.

AB
1ItemValue
2185 × (1+5/30)—
31RM→ 216 lb

The formula

The formula:

=B2 * (1 + reps / 30) // weight × (1 + reps/30)

How it works

How it works:

  1. Epley: weight × (1 + reps/30) — works best for reps in roughly the 1–10 range.
  2. A single rep returns the weight itself; more reps inflate the estimate.
  3. Alternative Brzycki: weight / (1.0278 - 0.0278×reps) — close but slightly different.
  4. Use the 1RM to set training percentages for programming.

Educational use only. These are general Excel formulas for learning spreadsheet techniques — estimates only, not training, medical, or nutrition advice. Individual results vary; consult a qualified professional before acting on them.

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Live demo

Weight lifted and reps.

Est. 1RM:

Variations

Brzycki formula

Alternative:

=weight / (1.0278 - 0.0278 * reps)

Training weight at %

From 1RM:

=ROUND(one_rm * percent, 0)

Reps at a weight

Rearranged Epley:

=(one_rm / weight - 1) * 30

Pitfalls & errors

Estimate, not a test. Formulas approximate; an actual max test is the only true 1RM.

Best at low reps. Accuracy fades above ~10 reps.

Round to plates. Round training weights to loadable increments.

Practice workbook

📊
Download the free Estimate 1-Rep Max (Epley) practice workbook
A 1RM sheet with the Brzycki, training-weight, and reps variants, plus 4 challenges with answers. No sign-up required.

Frequently asked questions

How do I estimate 1-rep max in Excel?
Use the Epley formula: =weight * (1 + reps / 30). 185 lb for 5 reps estimates ~216 lb.
What's the Brzycki formula?
=weight / (1.0278 - 0.0278 * reps) — an alternative 1RM estimate, slightly different from Epley.
How do I set training weights from 1RM?
Multiply by the target percentage: =ROUND(one_rm * percent, 0).

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