What a body scan tells you that the scale does not
Body weight is a single number made of fat, muscle, water, bone and everything else. Two people at 75 kg can look and perform very differently. If you are training and eating well, your weight may barely move while your body composition improves. A body scan tries to show that change by estimating how much of you is fat and how much is lean tissue.
How the Zafit AI body scan works
- Open Scan and choose Body.
- Take two photos: one from the front and one from the side, as the on-screen guide shows.
- Get your estimate. AI analyses the photos and returns composition estimates, such as body fat percentage and lean mass, and saves them to your history.
- Repeat over time. The value of a scan is in the trend, so repeat it every few weeks under similar conditions.
Tips for consistent photos
Estimates from photos are sensitive to how the photos are taken. To make comparisons meaningful:
- Use the same spot, lighting and camera distance every time.
- Wear fitted clothing, such as shorts and a fitted top, so your outline is visible.
- Stand relaxed and upright, with arms slightly away from your body.
- Scan at a similar time of day, ideally in the morning before eating.
- Hold the phone at a steady height, with your full body in the frame.
How much should you trust the numbers?
Treat any home body-composition number, from a smart scale, a handheld device or a phone camera, as an estimate. Clinical methods such as DEXA scans are more precise, and even they have error ranges. We do not publish an accuracy figure for the Zafit AI scan because we have not run a study that would support one. A sensible way to use it is to look at the direction of the trend over weeks, together with the mirror, the tape measure and how your clothes fit. Our explainer on how AI body scans work covers the technology and its limits, and measuring body fat at home compares four methods.
Pair the scan with progress photos
Numbers are one view; pictures are another. Zafit AI Pro includes progress photos with AI compare, so you can see changes side by side next to your scan history. Seeing both helps you notice real change, and it keeps a single noisy reading from discouraging you.
Turn the result into a plan
A scan is most useful when it changes what you do. If your body fat estimate is trending down and lean mass is holding, your plan is working. If lean mass drops during a diet, that is a cue to look at protein, training and the size of your deficit. The AI workout planner builds a training plan from your goals, and the AI calorie counter shows the eating side. You can also ask the AI coach about your numbers.
Who the body scan is for
- People who want to track change beyond bodyweight.
- People who do not own a smart scale or do not want to buy one.
- People who like seeing trends and are comfortable with estimates.
It is not a medical measurement, and it is not for diagnosing anything. If you have concerns about your weight or health, talk to a qualified professional.
Privacy
Body photos are sensitive. Zafit AI stores your data on its own server, encrypted in transit and at rest, and never sells it. Images you submit for a scan are processed by our AI provider to produce the result. Read the Data and Security page and the privacy policy for details, and you can delete your account and data at any time from within the app.
Frequently asked questions
How does a phone body scan work?
You take a front photo and a side photo. An AI model analyses your outline and proportions and estimates body composition values such as body fat percentage. It is an estimate, not a medical measurement.
Do I need a wearable or smart scale?
No. The Zafit AI body scan uses only your iPhone camera.
How often should I scan?
Every few weeks is enough for most people, under similar conditions each time. Day-to-day changes are mostly noise.
Is my body scan private?
Your data is stored on Zafit AI's own server, encrypted in transit and at rest, and never sold. Scan images are processed by our AI provider to generate the result.