Build your BMI Calculator with AI in under 5 minutes
Build a BMI calculator that works out your Body Mass Index in metric or imperial, shows your WHO category on a colour-coded gauge, and gives your healthy weight range — all in the browser.
How it works
Step 1
Describe your idea
Write a plain-text prompt describing what you want.
Step 2
AI builds it
FloopFloop generates production-ready code instantly.
Step 3
Deploy & go live
Your project is hosted on its own subdomain in minutes.
Why build with AI instead of hiring a developer?
| FloopFloop | Traditional developer | |
|---|---|---|
| Time to launch | Under 5 minutes | 2-8 weeks |
| Cost | From $0 | $5,000 - $50,000+ |
| Maintenance | Included | Ongoing retainer |
What is a bmi calculator?
A BMI calculator works out your Body Mass Index — weight divided by height squared — and tells you which of the World Health Organization's weight categories it falls in. It's one of the most-searched health tools because it's a quick, free way to screen whether your weight is in a healthy range for your height, whether you're tracking a goal, prepping for a doctor's visit, or just curious. The number itself is simple; what makes a calculator genuinely useful is showing it in context: which category you're in, where you sit on the scale visually, and what weight range would put you in the 'normal' band. A good one handles both metric and imperial, since people think in whichever they grew up with, and is honest that BMI is a rough screen — it can't tell muscle from fat — rather than a verdict.
Common features
- Metric and imperial inputs
- BMI to one decimal place
- The WHO category (underweight / normal / overweight / obese)
- A colour-coded gauge with a pointer
- Your healthy weight range for your height
- Boundary-accurate WHO cut-offs (18.5 / 25 / 30)
- Instant, browser-side calculation
- A clear 'screen, not a diagnosis' note
- Inputs remembered on the device
- Light and dark themes
Real-world examples
A quick check
Someone enters 70 kg and 175 cm, sees a BMI of 22.9 land in the green 'Normal' band, and notes the healthy range of about 57–77 kg.
Imperial inputs
A user flips to imperial, enters 154 lb at 5 ft 9 in, and gets the same result without doing any conversion.
Setting a target
Someone above the normal band reads off the healthy weight range for their height as a goal to aim for.
Why FloopFloop fits bmi calculator projects
A BMI calculator is a simple tool you want instant, ad-free, and private. FloopFloop ships the calculator you want — metric or imperial, a body-fat or waist-ratio add-on, your own styling — on your own domain, with every calculation running in the browser so nothing about your body leaves your device. The 'clinic' gauge that ships by default shows exactly where you land at a glance, and the whole thing is one prompt away from being whatever fits your need.
Try these prompts
Copy any prompt below and paste it into FloopFloop to get started.
Build a BMI calculator with a metric/imperial toggle. Metric takes weight in kg and height in cm; imperial takes weight in pounds and height in feet + inches. Show the BMI to one decimal, the WHO category (underweight / normal / overweight / obese) as a coloured pill, and a colour-coded gauge (blue→green→yellow→red on a 15–40 scale) with a pointer at the result. Also show the healthy weight range for the height. Compute everything in the browser, keep it deterministic so the first render is hydration-safe, and remember the inputs in localStorage. 100% client-side.
Create a BMI calculator like the health-site ones: enter weight and height, get the number and whether it's in the healthy range. Support metric and imperial. Keep it in the browser.
Build a body mass index tool with a visual gauge showing where I fall, and a dark theme.
Build a BMI calculator that also tells me the weight range that would put me in the normal BMI band for my height.
Frequently asked questions
How is BMI calculated?
What are the BMI categories?
What's the healthy weight range it shows?
Is BMI accurate for everyone?
Is my data uploaded?
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