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Body Fat Calculator

Estimates your body fat percentage using Navy method measurements (neck, waist, and height).

Body Fat Calculator

Estimates your body fat percentage using Navy method measurements (neck, waist, and height).

💡 This tool provides estimates as a guide. Individual results may vary.

Why This Matters for Busy Adults

The scale only tells part of the story. Two people can weigh the same but look completely different based on their body composition. Body fat percentage reveals how much of your weight is lean mass (muscle, bone, organs) versus fat. This matters because muscle is metabolically active and gives you that "toned" look, while excess fat can impact health and energy.

For anyone focused on feeling strong and capable—not just skinny—knowing your body fat percentage helps you track real progress. You might maintain the same weight while losing fat and building muscle, which the scale won't show. This matters whether you're preparing for a race, staying fit for your family, or simply wanting to feel confident.

Understanding the Numbers

Healthy body fat ranges vary by age and sex:

  • Men: 10-20% is fit/athletic, 21-25% is acceptable, 25%+ may indicate room for improvement
  • Women: 18-28% is fit/athletic, 29-35% is acceptable, 35%+ may indicate room for improvement

These are estimates—the Navy method is fairly accurate but not perfect. Use it to track trends over time rather than obsessing over the exact number. If your body fat decreases over weeks while you're getting stronger, you're on the right track.

How to Use This in Real Life

Measure yourself every 2-4 weeks under consistent conditions:

  • Same time of day (morning is best)
  • Before eating or drinking
  • Use the same spots for measurements each time
  • Track trends, not daily fluctuations

Combine this data with progress photos, how your clothes fit, and how you feel. Numbers are useful guides, but they're not the whole picture. Focus on sustainable habits that make you feel strong and energized.

Common Questions

How accurate is the Navy method?

It's reasonably accurate (within 3-4% of professional methods like DEXA scans) and more practical for home use. The key is consistency—measure the same way every time to track trends.

What's a realistic body fat loss rate?

Losing 0.5-1% body fat per month is sustainable and healthy. Faster rates usually mean you're losing muscle along with fat, which isn't ideal.

Should I aim for very low body fat?

Not necessarily. Extremely low body fat (under 12% for men, under 20% for women) can impact hormones, energy, and quality of life. Aim for a range where you feel healthy, strong, and can maintain it without constant restriction.

Want More?

Download our free fitness guide designed for busy parents

Ready for a Personalized Plan?

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