Know your numbers.

Progress in the gym comes from knowing your numbers and tracking them. UNITY 2B3's free fitness calculators cover BMI, body fat, one-rep-max and calorie targets — evidence-based, and tracked as you go so you can see it working.

Create your free account Open the fitness calculators

What you get

Everything to master fitness

Set the right targets

Calorie and macro targets based on your body and your goal, not guesswork.

Track real progress

BMI and body-fat trends so you know the plan is working.

Train to your max

One-rep-max estimates to program your lifts intelligently.

Free fitness tools

Jump straight into the calculators — free, no sign-up needed to try.

Open the fitness calculators All 40+ tools

FAQ

Fitness questions

What fitness calculators are included?

BMI, body fat, one-rep-max and calorie/TDEE targets — the core metrics for training and body composition.

Are they evidence-based?

Yes — the formulas are the standard, well-established ones used by coaches and clinicians.

Do they cost anything?

No. They're free, and a free account lets you track your numbers over time.

Level up your fitness — free.

Join UNITY 2B3 free. A personal plan, an AI coach, free tools and a real community across 10 areas of life. No card, ever.

Create your free account

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