ProAthletica was created because every fitness calculator we found was either inaccurate, plastered with distracting ads, or required creating an account to see the result.
We believe strength training tools should be fast, accurate, and completely free. Every calculator on this site uses proven, science-backed formulas — Epley for 1RM, Mifflin-St Jeor for BMR, standard Olympic loading math — and runs entirely in your browser. Zero data leaves your device.
Between sets at the gym, we noticed everyone reaching for their phones — to calculate their 1RM, figure out plate math, or check their macros. The existing tools were slow, broke the flow, and often got the math wrong.
So we built better ones. Each tool is designed for a single purpose: get you the answer in under two seconds and let you get back to training.
1 Rep Max Calculator — Epley and Brzycki formulas with training zone breakdown.
Protein & Macro Calculator — Mifflin-St Jeor BMR with goal-based adjustments.
Barbell Plate Loading Calculator — Visual plate math for any bar.
Workout Volume Tracker — Track sets, reps, weight, and volume trends.
Equipment Comparison Tool — Side-by-side product comparison.
Home Gym Space Planner — Room layout and fit checking.