One Rep Max Calculator

One Rep Max Calculator

Learn your estimated one-rep max (1RM) using the calculator below to target your strength goals more effectively.

Finding 1 rep max can be helpful for understanding your current strength level, building programs, and even more! Find yours below!

NASM 1RM Conversion Chart PDF

Table from the NASM website.

Or you can check out our bench press max chart here for more specific numbers.

Looking to boost your strength and performance? Use our one rep max calc to accurately determine the maximum amount of weight you can lift for one complete repetition.

This tool takes into account your current strength level. It can also help you build an effective training program to reach your fitness goals.

What is a One Rep Max?

One rep max (1RM) is the maximum amount of weight that you can lift for one complete repetition. Knowing your 1RM can help you build an effective weightlifting program to maximize it.

How Does Our Calculator Work?

It uses a customized equation to accurately determine your 1RM range. It predicts your max based on the amount of weight you can lift for multiple reps.

Provide the weight and number of repetitions. Then it will instantly generate your 1RM. It’s as simple as that!

Which Factors Can Affect Your Estimate?

Factors such as body weight, neuromuscular exhaustion of the muscle from fatigue, and technique variations can affect the calculation. These all have a significant impact on the value estimated.

Finding Your True One Rep Max

Are you about to attempt a new 1RM? Use the 1RM Warm-up Calculator below! You can also keep reading to determine how much weight you should use to warm up for the best results!

Enter the weight you plan to attempt below. Then the 1RM warm-up calculator will show you exactly what weight you should lift for your warmup.

More experienced lifters will benefit more from a true one rep max test as theirs takes longer to increase. Just make sure to lift safely and intelligently.

Here is another proven method from Layne Norton for finding your true one rep max.

Warming up to a 1 Rep Max

Warming up can make all the difference in your training. It is especially important when you plan on attempting a 1RM. A good warm-up may lower your chances of injury. It also increases the likelihood of a successful PR attempt.

How to Calculate Warmup Sets

Here is a simple and effective way to calculate warm up sets and reps:

1. 30% estimated 1RM for 8 reps
2. 40% for 6 reps
3. 50% for 4 reps
4. 60% for 2 reps
5. 70% for 1 rep
6. 80% for 1 rep

Testing for Your 1 Rep Max

1. 90-94% of estimated 1RM for 1
2. 96-100% of estimated 1RM for 1
3. 100-104% of estimated 1RM for 1

When testing it’s of course essential to use a spotter or another similar safety precaution, especially for bench press. There is no point in injuring yourself!

How Often Should You Test 1RM

You should only check your maximum strength once every 3-4 months at most. Lifting loads over 90% of your max can lead to damaged muscles and tendons. It also increases your chances of serious injury and even decreases gym performance.

Testing your 1RM too often can lead to:

• overuse/chronic injury
• serious injury
• neural fatigue
• hormonal disturbances
• decreased immune function
• muscle atrophy
• increased body fat

Alternatives to Testing Your True Max

Performing a one rep max set isn’t the only reliable way to find your max. Although it is the most accurate, it is also the hardest on your body and will not increase your strength. Here are some safer alternatives.

Multiple Rep Max

One common way to gauge strength on a specific lift is to perform a 2-5 rep max set. This is less dangerous and can be performed about once a month.

This is precisely what 1RM calculators come in handy for!

RPE

An RPE-based rep max is similar to a rep test; but, you aren’t taking yourself to true failure with it. 

Say you lift a specified weight for three reps at an 8 RPE (8 out of 10 rate of perceived exertion). If you lift a heavier weight for the same reps at the same RPE, you know you are making progress.

This style of repetition maximum test is significantly easier on the body. It also helps increase strength (unlike a true 1RM test) and can be done about once a week.

How to Find My One-Rep Max with the One Rep Max Calculator

Often, trainers and coaches set up programs using your one-rep max as a reference point. Especially if they don’t know your actual strength level. This allows the trainer to set an effective program without knowing your current strength.

Here are some things to remember when testing your 1RM:

• The lower your reps, the more accurate your estimate will be
• Don’t count reps with bad form
• Remember that each lift has its own 1RM- Don’t use bench press to calculate incline bench press

What Percentage to Use For Training

Speed and Power: 50-60%

Muscle Size: 70-80%

Strength: 85-95%

These numbers aren’t the only way to train, mix up the percentage of 1RM and rep range. They are just some recommendations based on methods that are proven to give results.

There are other ways to get results. Don’t be afraid to try new methods and mix things up. The one rep max calculator is meant to be a tool, not the answer to your strength concerns.

Not Happy With Your Current One Rep Max?

Here are some tips to help you get those numbers up!

Creatine has been proven to increase one rep max

If you are trying to increase your one rep max, 5 grams a day of creatine should absolutely be part of your supplement regimen.

Order Creatine

Train Close to Your One Rep Max

Try training at 80% of your maximum for four sets of five on week one. Then week two gradually increase the percentage of your max and so on.

Once you can perform this set and rep scheme for 87% of your max, try testing again.

Perform Walkouts or Holds

Sometimes you fail to pull off a new max attempt simply because you haven’t ever held that weight before. Simply load up the bar with the weight you want to lift (your 1RM or more). Then unrack it (walk out with it in the case of squats), hold it for a few seconds, and put it back on the rack.

Train Specific Ranges of Motion

If you are getting hung up on a specific portion of a given exercise, try these:

• Bench Lockout– Use boards or pins to shorten the range of your bench motion to just the top half.
• Deadlift Lockout– Perform rack pulls, lifting the weight from the mid-thigh position.
• Coming out of the Hole: Squats- Perform low box squats from below your typical squat depth.

Make sure to work with a spotter any time you training near your maximum.

Follow a Program

If your main exercise goal is to increase your 1RM for a given exercise, follow a strength training program built to do just that.

For beginner lifters or those who have never followed a strength training program, use Stronglifts or a similar program.

Just need to push yourself to the next level? Try other powerlifting programs like Smolov Jr. or browse all of our programs here.

What is the Most Common One Rep Max Calculator Formula?

There are several different formulas. The most common is the weight lifted divided by the total of 1.0278 minus the reps performed times 0.0278. This number is then rounded down to the nearest five.

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