Calibre Biometrics has filed for bankruptcy. The servers are still running, but could be shut down at any time. Your hardware is fine — it just needs software that works without a server. That's OpenSpiro.
Calibre Biometrics LLC, the manufacturer of the Calibre Bio portable VO2 analyzer, filed for Chapter 7 bankruptcy in March 2026 and ceased operations. Their Android companion app requires a server connection to function — the servers are still running for now, but could be shut down at any time. Without a server, the app stops working entirely.
The hardware itself is unaffected. The Calibre Bio device uses standard Bluetooth Low Energy to stream breath-by-breath sensor data.
OpenSpiro connects directly to your Calibre Bio device via Bluetooth. No server, no account, no internet connection required. All data stays on your machine.
| Feature | Calibre App | OpenSpiro |
|---|---|---|
| Server required | Yes (future uncertain) | No — 100% local |
| Platform | Android only | macOS + Windows |
| Power meter integration | No | BLE + ANT+ (Garmin, Favero, Wahoo, ...) |
| Smart trainer control | No | FTMS ERG mode |
| Test protocols | None | Free: VO2max Ramp, RMR · Pro: FatMax, Efficiency, AI |
| Multiple athletes | Cloud account | Local profiles, no login |
| Data export | No | CSV + JSON |
| Session replay | No | Full scrubber with chart + metrics |
| VT1/VT2 detection | No | Automatic |
| Calibration | In-app | In-app (same 30s ambient flow) |
| Price | Free (server-dependent) | Free (Pro coming soon) |