Free gym calculators, no signup
Practical calculators for people who train with a barbell: estimate your one rep max, check your strength level, find your heart rate zones, plan warm-up sets and load the bar right. Built by the team behind the APX training app, free to use.
One Rep Max (1RM) Calculator
Estimate your max for any lift from a weight and rep count. Epley and Brzycki formulas plus a training percentage table.
Strength Level Calculator
See how your bench, squat, deadlift or press ranks against bodyweight-based strength standards, from beginner to elite.
Heart Rate Zone Calculator
Get your five training zones in bpm from your age, with the more precise Karvonen method if you know your resting heart rate.
Warm-up Sets Calculator
Turn your working weight into a ramped warm-up: bar, 50%, 70%, 85%, ready to lift. Rounded to real plate loads.
Barbell Plate Calculator
Enter a target weight and see exactly which plates to load per side, for kg and lb bars.
Wilks & DOTS Calculator
Compare strength across bodyweights with the two scores powerlifting actually uses.
Why these calculators
Every tool here answers a question that comes up in real training: how heavy should I go, am I actually getting stronger, what should my warm-up look like, which plates go on the bar. The same logic powers workouts inside APX, where your plan, working weights and history live in one place instead of a notes app.
Want the plan, not just the math?
APX builds a personalized gym plan and tracks every set, so the numbers work themselves out.
Download APX free