Train smarter. Eat better. Perform better.
16 free, precise calculators for training and nutrition — macros, body fat, one rep max, heart rate zones and more. Enter your numbers, get a clear answer, no account required.
Explore by category
Every calculator, organised by what you're working on.
Macros, protein, water & creatine
4 calculators to dial in what you eat and drink each day.
Body compositionBody fat, FFMI, ideal & lean mass
4 calculators for tracking how your body is actually changing.
StrengthOne rep max, plates & Wilks/DOTS
3 calculators for lifters tracking relative strength.
Cardio & activityHeart rate, pace, VO2 max & steps
5 calculators for runners and anyone tracking daily activity.
Featured calculators
The four tools people reach for first.
Macro Calculator
Turn your daily calorie target into a protein, carb and fat split.
NutritionBody Fat Percentage
Estimate body fat using the US Navy circumference method.
Body compositionOne Rep Max
Estimate your 1RM and training percentage zones.
StrengthHeart Rate Zone
Get personalised training heart rate zones for cardio.
Cardio & activityFast
Instant results in your browser — no loading spinners, no waiting.
Free, always
Every calculator is free to use, with no account or payment required.
Science-based
Every formula is an established one used in sports science and clinical nutrition.
Latest articles
Practical guides that sit alongside the calculators.
How to Count Macros (Without Overthinking It)
A practical, no-fuss approach to daily tracking.
Body Recomposition, Explained
How macros support building muscle and losing fat together.
Natural Muscle Growth: What to Expect
Realistic timelines for building lean mass without shortcuts.
Common questions
Yes — every calculator on SH Fitness Tools is free to use, with no sign-up required, now and in the future.
If you're new here, the Macro Calculator and Body Fat Percentage Calculator are a popular starting point for building a full picture of your nutrition and body composition.
No — every calculator gives a general estimate for informational purposes only. See our disclaimer for details, and speak with a qualified professional for individual medical or dietary advice.
Ready to get your numbers?
16 free tools across nutrition, body composition, strength and cardio.
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