BMI Calculator works out your Body Mass Index as you adjust your height and weight, and shows where that sits with a colour-coded chart, your healthy weight range, and how far from it you are. Every calculation is saved to a weight log automatically, and the chart smooths out the day-to-day swings so you can see the real direction of travel. The app has no internet permission at all, which means your measurements cannot leave your phone.

Here are just a few of the great features of BMI Calculator:

• BMI in seconds, with context: your figure updates live as you adjust the sliders, with a clear category, a colour-coded chart and your healthy weight range. Choose WHO international or WHO Asian (WPRO) cutoffs.
• A weight trend you can trust: every entry is logged automatically and the chart smooths out daily ups and downs. Missed a day? Log a weigh-in for a past date, and edit any entry later.
• Goals with a realistic date: set a goal weight and follow a projected date for reaching it, alongside your ideal weight, your BMR and TDEE calorie needs, and a safe steady pace rather than a crash plan.
• Family profiles: one app for the household — each person keeps their own history, units and goal, and you switch between them in a tap.
• More than BMI: body fat by the US Navy tape method with guidance on where to measure, waist-to-height and waist-to-hip ratios, BMI Prime and Ponderal Index. Every extra measurement is optional.
• Your units, and your data: kilograms, pounds, or stone and pounds; centimetres or feet and inches. Export a PDF for a doctor’s visit, and back up to JSON or CSV to restore on a new phone.

A weight tracker that keeps your measurements on your own phone. Download BMI Calculator and start your log.

For adults 18 and over. This app is not a medical device and does not diagnose, treat, cure or prevent any medical condition. BMI is a screening tool — always consult a healthcare professional for medical advice, diagnosis or treatment.