Health & Benefits
Health and wellness calculators for BMI, BMR, TDEE, body composition, and medical cost planning. Educational estimates to inform conversations with healthcare providers—not medical advice.
These tools help you understand baseline health metrics and plan for medical expenses. Whether you're estimating calorie needs, comparing insurance plans, or tracking fitness progress, we show our formulas and let you adjust inputs. Remember: these are educational estimates, not substitutes for professional medical guidance. You might also find our Calculate take-home pay for benefits planning, Build a medical emergency fund, Budget for health expenses and Compare HSA vs FSA tax savings helpful for related calculations.
Health & Benefits Guide
Last updated: February 17, 2026
Last updated: February 17, 2026
What you can do in Health & Benefits
- •Estimate your BMI and see where it falls on the standard categories (these are starting points, not diagnoses)
- •Calculate BMR and TDEE to understand your baseline calorie needs for maintaining, losing, or gaining weight
- •Get a rough body fat percentage estimate using simple measurement formulas
- •Figure out daily water intake goals based on your weight and activity level
- •Compare health insurance plans by total annual cost—not just monthly premiums
- •Plan HSA contributions to maximize tax savings while covering expected medical expenses
- •Track fitness progress with weight and measurement logs over time
- •Estimate heart rate training zones for cardio workouts
Accuracy, assumptions, and sources
- •All health estimates use standard formulas (Mifflin-St Jeor for BMR, Navy method for body fat). Individual metabolism varies.
- •BMI doesn't account for muscle mass, bone density, or fat distribution—athletes and muscular people may show misleading numbers.
- •Calorie estimates can vary 10-15% from actual needs. Use them as starting points, then adjust based on real results.
- •Insurance cost comparisons assume you meet your deductible. Low-use years favor high-deductible plans.
- •These tools provide general information, not medical advice. Always consult healthcare providers for health decisions.
- •Pregnancy and fertility estimates use average cycle lengths. Individual cycles vary significantly.
Pick the right calculator fast
- If you want to know your calorie needs→BMR / TDEE Calculator
- If you're tracking body composition→Body Fat Percentage Estimator
- If you're comparing health insurance plans→Medical Out-of-Pocket Calculator
- If you want to optimize HSA contributions→HSA Contribution Planner
- If you're planning cardio training zones→Heart Rate Zone Calculator
- If you want to estimate your one-rep max→One-Rep Max Calculator
- If you're tracking your sleep patterns→Sleep Debt Calculator
- If you want to estimate pregnancy timing→Pregnancy Due Date Calculator
Common mistakes to avoid
- •Treating BMI as a health diagnosis—it's a screening tool, not a measure of actual health.
- •Using TDEE estimates without adjusting based on real-world results over 2-4 weeks.
- •Choosing health plans based only on premiums without calculating total annual costs including deductibles and copays.
- •Confusing body fat percentage formulas—our tool uses the Navy method, which may differ from calipers or DEXA.
- •Setting calorie targets too aggressively—sustainable changes work better than crash diets.
- •Ignoring the triple tax advantage of HSAs (tax-free contributions, growth, and withdrawals for medical expenses).
- •Using metric and imperial units inconsistently in the same calculation.
- •Expecting precision from estimation tools—these are approximations for general guidance.
Editorial policy
- ✓All calculators provide educational estimates, not medical diagnoses or professional health advice.
- ✓We use established formulas (Mifflin-St Jeor, Navy method) and cite them in each tool.
- ✓Results depend on the accuracy of your inputs—double-check measurements.
- ✓We don't store personal health data. Calculations run in your browser.
- ✓Formulas and assumptions are disclosed inside each tool.
- ✓Found an error or have a suggestion? Email hello@everydaybudd.com.
Top Picks
All Health & Benefits Tools
Frequently Asked Questions
Are these health calculators a replacement for medical advice?
No. Our calculators provide educational estimates only. BMI, body fat, calorie needs, and similar metrics are starting points for conversation with healthcare providers—not diagnoses. Always consult a doctor for health decisions.
How do I choose between health insurance plans?
Use our Medical Out-of-Pocket Calculator to compare plans. Enter premiums, deductibles, coinsurance, and expected medical spending. It shows total annual costs and break-even points to identify the best plan for your situation.
What's the difference between deductible and out-of-pocket maximum?
Deductible is what you pay before insurance starts covering. Out-of-pocket maximum is the most you'll pay in a year (including deductible, copays, coinsurance). After hitting OOP max, insurance covers 100% of covered services.
Why do BMI and body fat estimates differ from my doctor's measurements?
Our calculators use standard formulas (like the Navy method for body fat) which are approximations. Clinical measurements using calipers, DEXA scans, or bioimpedance are more accurate. Use our tools for general tracking, not clinical assessment.
How accurate are calorie and TDEE calculators?
TDEE estimates can vary 10-15% from actual needs due to individual metabolism differences. Use our BMR/TDEE Calculator as a starting point, then adjust based on real-world results over 2-4 weeks.
How much should I contribute to my HSA?
2025 HSA contribution limits: $4,300 (individual), $8,550 (family), plus $1,000 catch-up if age 55+. Contribute enough to cover expected medical expenses, treating it as a triple-tax-advantaged retirement account.