US Navy Body Fat Calculator: because I wanted a straight answer

I’ve never been a fan of guessing when it comes to body composition. A few months ago, I was trying to get a rough sense of where I stood — not for a competition, just for my own notes. I knew the US Navy method existed (it’s been around forever), and I figured I’d just punch my numbers into a calculator and move on.

Well, that turned into a small rabbit hole. Most calculators I found were either buried inside fitness blogs with tons of ads, or they asked for my email before showing results, or they just looked like they hadn’t been updated since 2008. I don’t need a “body fat analyzer” that tries to sell me a meal plan. I just need the formula, applied correctly, with no extra noise.

So I made one myself — a dead-simple US Navy Body Fat Calculator. You give it your height, neck, waist, and hip measurements (hips are optional for men, required for women), and it returns your estimated body fat percentage using the standard Navy circumference equations. That’s it. No signup, no spam, no lifestyle quiz.

I wanted something that felt like a reference tool, not a marketing funnel. If you’re familiar with the method, you know it’s not the last word in accuracy — but it’s practical, reproducible, and good enough for tracking changes over time. I use it myself now, and it lives in my bookmarks.

If you’ve been using a different method or just want a quick check without the fuss, give it a shot. I hope it’s useful.

Thanks for reading.
— Nick, ToolsForUse