Diabetes is a most common disease worldwide. Acetone in exhaled breath is a known biomarker of Type-1 diabetes. An exhaled breath analyzer has been invented and developed by our team to diagnose diabetes as a non-invasive alternative of the currently used blood-based diagnostics. This device utilizes a chemiresistor based on ferroelectric tungsten oxide nanoparticles that detects acetone selectively in breath-simulated media. Real-time monitoring of the acetone concentration is demonstrated, making this invention a revolutionary, non-invasive, diabetes diagnostic tool.