One Rep Max Calculator

The one rep max calculator is your essential tool for strength training. Our one rep max calculator uses proven formulas to estimate your maximum lifting capacity.

One Rep Max Calculator

Calculate your one rep max and get training percentages for different goals.

Results

Your One Rep Max:

Training Percentages:

Strength (85-95%)

Power (75-85%)

Hypertrophy (65-75%)

Endurance (50-65%)

Results

Your One Rep Max:

Training Percentages:

Strength (85-95%)

Power (75-85%)

Hypertrophy (65-75%)

Endurance (50-65%)

Why Use Our One Rep Max Calculator

The one rep max calculator is trusted by thousands of strength athletes worldwide.

Scientific Accuracy

Our one rep max calculator uses research-validated formulas for precise results.

Multiple Formulas

The one rep max calculator offers multiple calculation methods to suit your needs.

Safety First

Get safe estimates using our one rep max calculator without maximal lifting.

How the One Rep Max Calculator Works

Brzycki Formula

The one rep max calculator implements the Brzycki formula: Weight × (36 / (37 - Reps))

Epley Formula

The one rep max calculator also uses the Epley formula: Weight × (1 + 0.0333 × Reps)

Lander Formula

Our one rep max calculator includes the Lander formula: (100 × Weight) / (101.3 - 2.67123 × Reps)

Using the One Rep Max Calculator

Step 1: Choose Your Exercise

The one rep max calculator works best with compound exercises like squats, bench press, and deadlifts.

Step 2: Enter Your Data

Input the weight and repetitions into the one rep max calculator fields.

Step 3: Select Formula

Choose your preferred formula in the one rep max calculator.

Safety When Testing Your One Rep Max

While the one rep max calculator provides estimates, safety should always be your priority. The one rep max calculator helps you avoid unnecessary risk during training.

Safety Checklist

  • Use the one rep max calculator before attempting maximal lifts
  • Always warm up properly before testing
  • Maintain proper form throughout your lifts
  • Have spotters present for heavy attempts
  • Use the one rep max calculator regularly to track progress safely

One Rep Max Calculator FAQ

How accurate is the one rep max calculator?

Our one rep max calculator provides highly accurate estimates when used with sets of 10 reps or less. The accuracy tends to decrease with higher repetitions due to factors like fatigue and form breakdown.

How often should I use the one rep max calculator?

You can use the one rep max calculator every 4-6 weeks to track your strength progress. This timeframe allows for sufficient adaptation and progress while avoiding premature testing.

Which exercises work best with the one rep max calculator?

The one rep max calculator works best with compound exercises like squats, bench press, and deadlifts. These movements are easier to standardize and have more consistent strength curves.

How can I improve my one rep max?

Use the one rep max calculator to track progress while following a structured strength training program. Focus on progressive overload, proper form, and adequate recovery between training sessions.

Why are there different formulas available in the calculator?

Different formulas have been developed through various research studies and may be more accurate for different individuals or exercises. The Brzycki formula, for example, tends to be more accurate for bench press, while the Epley formula might work better for squats.

Should beginners use the one rep max calculator?

Yes, beginners can benefit from using the calculator to establish baseline numbers and track progress. However, they should focus on developing proper form before attempting heavy weights or actual one-rep maxes.

What's the best rep range to use for accurate calculations?

The most accurate results typically come from sets performed with 3-5 repetitions. While the calculator can work with up to 15 reps, accuracy tends to decrease as rep counts increase beyond 5-6 repetitions.

How should I warm up before testing my max?

Start with light dynamic stretches, then perform progressively heavier sets with low reps. A typical warm-up might include 2-3 sets at 50%, 70%, and 85% of your estimated working weight before attempting your test set.

Can I use the calculator for isolation exercises?

While the calculator can be used for isolation exercises, the results may be less accurate due to factors like muscle fatigue and varying movement patterns. It's most reliable when used with compound movements.

How do different factors affect my one rep max?

Various factors can influence your one rep max, including sleep quality, nutrition, stress levels, time of day, and overall recovery state. For most accurate results, test when you're well-rested and properly fueled.

Training with Your One Rep Max

Training Percentages

Once you've used the one rep max calculator, use these percentages for training:

  • Strength: 85-95% of one rep max
  • Power: 75-85% of one rep max
  • Hypertrophy: 65-75% of one rep max
  • Endurance: 50-65% of one rep max