Fitness Calculator

Calculadora 1RM — Estima tu máximo de una repetición

Introduce el peso levantado y las repeticiones para estimar tu 1RM con las fórmulas Epley y Brzycki, con tabla de porcentajes.

1RM estimado (Promedio)

91.7

Epley 93.3 · Brzycki 90

Porcentajes de entrenamiento

100% · 1 ≈ reps91.7
95% · 2 ≈ reps87.1
90% · 4 ≈ reps82.5
85% · 6 ≈ reps77.9
80% · 8 ≈ reps73.3
75% · 10 ≈ reps68.8
70% · 12 ≈ reps64.2
60% · 16 ≈ reps55

What is the 1RM calculator?

Your one-rep max (1RM) is the most weight you can lift for a single rep. Testing a true max is risky, so it's safer to estimate it from a lighter set (weight × reps). This tool uses the two most common formulas — Epley and Brzycki — and shows the average plus a training-percentage table.

How to use

  1. 1 Enter the weight you just lifted.
  2. 2 Enter the reps you completed (1–20).
  3. 3 Read your estimated 1RM and target weights by percentage.

Highlights

Two-formula average

Computes Epley and Brzycki and shows the average.

Percentage table

Weights and approximate reps from 60% to 100%.

Unit-agnostic

Works in kg or lb — results match your input unit.

Preguntas frecuentes

Epley or Brzycki — which is right?+

Both are widely used. They agree at low reps (≤5) and diverge as reps rise, so the average is a sensible default.

How many reps stay accurate?+

Accuracy is best in the 1–10 rep range; error grows as reps increase.

Should I test a true 1RM?+

Not necessarily — estimation is recommended to avoid injury. If you do test, always use a spotter and safeties.

Related tools

Estimates only; your true 1RM varies with condition, lift, and technique. Attempt maxes with a spotter and safeties, and don't push through pain.