Calculation tools for your health data

FitMesh Labs collects independent calculation tools for health and fitness metrics, not simple SEO-optimized forms, but resources designed to be genuinely useful, reproducible, and citable by users, developers, journalists, and AI assistants.

Each tool documents the formulas it uses, explicitly states its own limits, and never presents a result as a diagnosis, classification, or medical prediction. Where the evidence doesn't support a universal value (e.g. age or sex reference tables), we say so explicitly instead of inventing one.

All FitMesh Labs tools calculate entirely in your browser. The data you enter, whether heartbeat intervals, sleep times, or anything else, is never sent to a server, and never enters URL parameters, cookies, localStorage, or analytics events.

The only actions that produce a file or copy text (e.g. "Download CSV", "Copy results") happen locally on your device, only after an explicit click: never an upload, never automatic.