BodyCalc

Hey IH 👋

I'm dayu2333jinyul, and I just shipped my first side project: **BodyCalc** (bodycalctool.com)

## What it does

BodyCalc is a free health calculator that takes your stats once and outputs everything on a single page:

- BMI

- BMR (3 formulas side by side — Mifflin-St Jeor, Harris-Benedict, Katch-McArdle)

- TDEE (total daily energy expenditure)

- Ideal weight (5 formulas)

- Body fat percentage (US Navy Method)

- Waist-to-hip ratio

## Why I built it

I was tracking my fitness progress and had to visit 5 different websites. Each one made me re-enter my height, weight, age... over and over. Most calculators show only one number, push ads in your face, or require signup.

I wanted: one page, enter stats once, see everything. So I built it over a weekend.

## The stack

- Plain HTML/CSS/JS — no frameworks, no build step

- All calculations run client-side, zero server cost

- Deployed on Cloudflare Pages (free tier)

## Numbers so far

- Launched: June 2024

- Traffic: ~50-200 daily visitors (organic, no ads yet)

- Revenue: $0 (it's completely free, no monetization yet)

- Time invested: one weekend initial build + ongoing tweaks

## What I learned

1. The "US Navy Method" for body fat is surprisingly accurate — and almost nobody knows about it

2. Showing 3 BMR formulas side by side gets people curious — it's my most commented feature

3. Static sites on CF Pages are incredible for solo devs. Zero maintenance.

## What's next

I'm not sure yet. Maybe a PWA, maybe add a meal planner. Would love to hear what you think.

If you have feedback on the UX or features, I'm all ears. And if you know any fitness communities that might find this useful, I'd appreciate the pointer 🙏