Learn your one-rep maxes, how they measure up, and how to easily and correctly use them to help you make better progress in your fitness goals.

One Rep Max Calculator Detailed Guide

One repetition maximum is the biggest weight you can lift per one repetition in a specific exercise. One rep max can also be used to determine the value of your weights in your training set.

For example, if you want to work 12 repetitions, you can recalculate it even if you know the weight required for 4,6, or even 10 repetitions.

For example, you get a program which says you to work on 70% of one rep max. You will have to options – estimate it roughly, or use the table. Max rep calculator is always an easier choice since everything can be done with a very simple proportion. The only way to know the exact value is doing it, that’s for sure, but equation will save you from many possible complications!

Here are benefits of max rep calculator:

• There is no need to burden your muscles;
• Injury risk is significantly decreased;
• You can calculate the approximate values and program your training session more precisely;
• You can get a better overall picture and monitor your progress easier.

One-Rep Max Calculator – Instructions And Recommendations

You need to understand three ways of counting, from three authors – Brzycki, dos Remedios, and Baechle.

% 1RM	Number of repetitions	Brzycki	Baechle	dos Remedios
These are data from three authors. There are differences in the calculations of 1 RM.	1	100	100	100
	2	95	95	92
	3	90	93	90
	4	88	90	87
	5	85	87	85
	6	83	85	82
	7	80	83
	8	78	80	75
	9	76	77
	10	75	75	70
	11	72
	12	70	67	65
	15		65	60

Baechle TR, Earle RW, Wathen D (2000). Essentials of Strength Training and Conditioning, 2: 395-425.

Brzycki, Matt (1998). A Practical Approach To Strength Training. McGraw-Hill.

Dos Remedios R (2007) Men’s Health Power Training, Rodale Inc. 23.

In bodybuilding, the most important zones are 8-12 repetitions, because it targets hypertrophy oriented strength. Sometimes bodybuilders stick to 15 or even more repetitions, depending on the training goal. This type of training targets muscular endurance.

While 1-5 repetitions are great for maximum strength, 6-8 repetitions are a great choice for the power development.

Learn How To Use Max Rep Calculator – Few Basic Examples

Let’s say you did 12 repetitions with 150 kilograms on a bench press. That means 150 kilograms is 70% of your 1 repetition maximum value (Brzycki). To be able to calculate one repetition maximum, all you need to do is divide those two numbers:

1 RM = weight / percentage = 150 / 0.70 = 214.28 kilograms

You can use a different author for an efficient max calculator too. According to dos Remedios, 12 repetitions mean 65% of one repetition maximum.

x: 150 = 100:65
x = 150 x 100 / 65
x = 230,76 kilograms

Generally, you will notice slight differences, depending on authors. But you can always calculate estimation values.

One more easy calculation, let’s say you know you can perform 8 repetitions with 100 kilograms, but you need to determine the value for 3 repetitions.

According to Baechle, 8 repetitions are 80% of 1 RM, while 3 repetitions are 93% of 1 RM.

You can lift 100 kilograms 8 times. Three repetitions can be calculated via simple proportion:

8 repetitions (percent: weight) = 3 repetitions (percent: weight)
80:100 = 93: x
x = 100*93/80 = 116,25 kilograms

Your one rep max value will depend on the number of your repetitions and the approach you choose between these three. No matter which one you choose, you won’t make a critical mistake.

When it comes to a squat max calculator or deadlift max calculator, the principle is the same. Is there a dependency between max squat calculator and deadlift calculator? No, every exercise is a unit for itself. For example, if you lift 200 kilograms on squat, this might and needn’t mean you will lift 300 kilograms on deadlift. Counting 1 RM for each exercise separately will keep your tracking progress accurate!

Final Word

Whether you are a professional lifter or a regular practitioner, you need to be aware of the possibilities of your body. Introduce yourself to the zones, choose your author, and learn to use one rep max calculator properly.

Don’t be too cruel towards yourself – doing 1RM every single day to determine your maximum would seriously harm your body and your training progress. Track your progress regularly, increase your weights as the time goes by, and enjoy transforming your body into Hulk-looking style!

If you have any question or suggestion please let us know in the comments below.