Weight gain plans, muscle gain timelines, and lean bulk calculators. Browse our free weight gain tools below — all calculators are instant, accurate, and require no sign-up.
Bulk Comparison Calculator — Compare lean bulk vs dirty bulk outcomes. See projected muscle gain, fat gain, and body composition changes over 3, 6, and 12 months.
Lean Bulk Calculator — Calculate optimal calories and macros for a lean bulk. Find your surplus, protein target, and projected muscle vs fat gain for clean bulking.
Child Growth Percentile Calculator — Calculate your child's weight, height, and BMI percentiles using WHO and CDC growth charts. Track growth from birth to age 20 with age and sex-matched comparisons.
Muscle Gain Timeline Calculator — Estimate your muscle gain potential over time using the Lyle McDonald model. Year-by-year projection based on training experience and genetic factors.
Rehydration After Weigh-In Calculator — Calculate your post-weigh-in rehydration plan for combat sports. Get fluid, electrolyte, and carb timing to maximize recovery before competition.
Weight Gain Plan Calculator — Calculate daily calorie surplus needed to gain weight safely. Plan your weight gain timeline with weekly targets for muscle building or underweight recovery.