Health & Fitness tools
Everyday health and fitness calculators covering BMI, BMR, calorie and macro needs, body composition, hydration, and training metrics like heart rate zones, VO2 max, and running pace. The formula used (Mifflin-St Jeor, Harris-Benedict, and so on) is named on each tool's page.
18 tools
Health & Fitness tools guides
Macronutrients Explained: How Protein, Carb, and Fat Targets Are Calculated
A calorie target on its own doesn't say anything about what to actually eat - macronutrient splits translate a single number into grams of protein, carbs, and fat, and each gram doesn't count the same toward that total.
Body Fat Percentage: Why the Scale Isn't the Whole Story
Two people can weigh the exact same amount and have very different body compositions - body fat percentage is what a plain scale weight can't tell you on its own.
BMR vs TDEE: How Your Calorie Needs Are Actually Calculated
The difference between the calories your body burns at rest and the calories it burns in a full day, and how that distinction is the basis of every calorie-goal number you've ever seen.
How BMI Is Calculated (And Why It's a Screening Tool, Not a Diagnosis)
The actual BMI formula, why it can't tell muscle from fat, and which other numbers give a fuller picture than BMI alone.
Frequently asked
Are these tools actually free?
Yes. Every tool on this page is free to use, with no usage limits, watermarks, or paywalled features.
Is my file or data uploaded to a server?
No. Every tool listed here processes your file or input directly in your browser tab; nothing is sent to YourFileKit's servers or any third party.
Do I need to create an account?
No sign-up is required to use any tool. An optional account only exists for saving preferences like favorites across visits.
Are these results medical advice?
No. They're general estimates from standard published formulas, meant for everyday reference, not a diagnosis or a substitute for a doctor, dietitian, or trainer.
Which calorie formula do you use?
BMR Calculator and Calorie Needs Calculator use the Mifflin-St Jeor equation by default, shown on the page alongside the result so you can see exactly how the number was reached.