Every flight log the Nano saves carries a digital signature, so anyone can confirm a log is genuine and exactly as the altimeter wrote it. An unedited log passes; if anything in the file has been changed, even a single character, it fails.
This page shows the ways to check a log. For how the signature works, see the security page.
On the Altimeter Cloud
The upload page is also the verify tool: there is no separate checker. Add your flight log, the .aclz or .csv file, or upload straight from the Nano with the USB upload tool, and every log is checked as it arrives. A genuine log is added and you are told it verified. An edited log fails verification and is turned away.
Each signature only ever creates one flight. If the log is already on the Altimeter Cloud, verifying it again doesn't add a new flight; you are shown a link to the original flight instead.
You don't need an account to verify a log, so you can use it to check a log someone has sent you.
With the API
If you want to check or upload logs from your own software, for example as a competition organiser handling many entries at once, the Altimeter Cloud has a public API for both:
| Endpoint | What it does |
|---|---|
| CSV Verification /api/csv_verify/ | Checks a CSV flight log is genuine and unedited, and returns the result with a few details such as the apogee and a unique flight identifier. |
| Upload API /api/upload/ | Verifies a flight log and adds the flight to the Altimeter Cloud. |
Both are open to everyone with no sign in needed. Without a key you can make 60 requests in 5 minutes, 600 an hour and 5,000 a day. A free API key from your profile raises that to 1,000, 10,000 and 50,000. Send the key in an X-API-Key header.
The request and response formats, the error codes and a live playground to try them in your browser are on the API pages. The API is free for clubs, competitions, flyers and personal projects.