If you want to know how much of your body is fat versus muscle, two names come up most often: the InBody (a bioelectrical impedance analyzer) and the DEXA scan (a dual-energy X-ray). Both go beyond the bathroom scale, but they work differently, and the right choice depends on what you are trying to learn.
An InBody sends a small, safe electrical current through your body and estimates fat, muscle, and water based on how that current moves through different tissues. A DEXA scan uses two low-dose X-ray beams to measure bone density, fat mass, and lean mass, and can break results down region by region.
DEXA is often treated as a research-grade reference for fat and bone measurement, but it is more expensive, less available, and involves a small radiation dose. An InBody is fast, radiation-free, repeatable, and well suited to tracking change over time, especially when the test is done under consistent conditions (same time of day, similar hydration).
For most people tracking a weight-loss, muscle-building, or GLP-1 medication plan, a repeatable InBody test paired with a dietitian who interprets the results is the practical choice. What matters most is not a one-time number but the trend, and whether the changes you see are fat coming off while muscle stays on.