Bench Press Calculator

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bench press calculator
Epley Formula (Standard)Brzycki FormulaLander FormulaLombardi Formula
lbkg
 
Estimated One-Rep Max:


function calculateResult(){var w=parseFloat(document.getElementById('weight').value);var r=parseFloat(document.getElementById('reps').value);var f=document.getElementById('formula_type').value;var u=document.getElementById('unit').value;var showT=document.getElementById('showTable').checked;if(isNaN(w)||isNaN(r)||r<=0||w20){alert('Results for reps over 20 are less accurate.');}var max=0;if(f==='epley'){max=w*(1+(r/30));}else if(f==='brzycki'){max=w/(1.0278-(0.0278*r));}else if(f==='lander'){max=(100*w)/(101.3-(2.67123*r));}else if(f==='lombardi'){max=w*Math.pow(r,0.1); if(r==1)max=w;}document.getElementById('resultValue').innerHTML=Math.round(max);document.getElementById('unitValue').innerHTML=u;var tableHTML='';var percents=[95,90,85,80,75,70,65,60,50];for(var i=0;i<percents.length;i++){var val=Math.round(max*(percents[i]/100));tableHTML+='';}tableHTML+='
PercentageWeight ('+u+')
'+percents[i]+'%'+val+' '+u+'
';if(showT){document.getElementById('percTable').innerHTML=tableHTML;document.getElementById('percTable').style.display='block';}else{document.getElementById('percTable').style.display='none';}document.getElementById('calculatorAnswer').style.display='block';}

Using the Bench Press Calculator

A bench press calculator is an essential tool for athletes, powerlifters, and fitness enthusiasts who want to track their strength progress safely. Instead of attempting a dangerous maximum lift without proper preparation, this tool estimates your One-Rep Max (1RM) based on sub-maximal efforts. Whether you are aiming to set a personal record or designing a new training block, knowing your 1RM allows you to program percentages accurately for hypertrophy, power, or endurance phases.

By entering your most recent heavy set weight and the number of clean repetitions performed, the calculator applies scientifically validated formulas to predict your absolute limit.

Weight Lifted
The amount of resistance (in pounds or kilograms) you successfully bench pressed for a set.
Repetitions
The total number of times you lifted the weight with proper form. For the most accurate calculation, use sets between 2 and 10 reps.
Calculation Formula
Different mathematical models used by sports scientists (like Epley or Brzycki) to estimate maximal strength based on fatigue rates.

How It Works: The Science of 1RM

The bench press calculator uses linear or non-linear regression models. Most formulas assume a predictable relationship between the weight moved and the number of repetitions until failure. The most famous model, the Epley Formula, suggests that your 1RM is roughly 1/30th more than your weight lifted for every rep performed.

Epley Formula: 1RM = Weight × (1 + (Reps / 30))

  • Epley: Best for general strength and higher repetition ranges.
  • Brzycki: Often considered more accurate for lower repetition ranges (3-8 reps).
  • Lander: A slightly different coefficient focused on explosive power athletes.
  • Lombardi: A non-linear approach using an exponential factor, often used in powerlifting circles.

Calculation Example

Example: A lifter successfully completes a set of 225 lbs for 5 repetitions and wants to know their estimated 1RM using the Epley formula.

Step-by-step solution:

  1. Input Weight = 225 lbs
  2. Input Reps = 5
  3. Divide reps by 30: 5 / 30 = 0.1667
  4. Add 1 to the result: 1 + 0.1667 = 1.1667
  5. Multiply by the weight: 225 × 1.1667 = 262.5 lbs
  6. Result: Your estimated One-Rep Max is 263 lbs.

Common Questions

How accurate is a bench press calculator?

For most people, these formulas are accurate within 3-5%. However, accuracy decreases as the repetition count increases. A 3-rep set provides a much better prediction of a 1RM than a 15-rep set because high-rep sets are often limited by cardiovascular endurance or lactic acid buildup rather than absolute muscular strength.

Why should I use a calculator instead of testing my max?

Testing a true 1RM is extremely taxing on the central nervous system (CNS) and carries a higher risk of injury, especially for the shoulders and pectorals in the bench press. Using a bench press calculator allows you to gauge your strength level without the recovery time required after a maximal effort attempt.

What is a "good" bench press?

Bench press strength varies significantly by body weight, age, and gender. Generally, for an average male, a 1x bodyweight bench press is considered "intermediate," while a 1.5x bodyweight press is "advanced." Elite powerlifters often reach 2x bodyweight or more.

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