Le Mans Ultimate saves telemetry as .duckdb files. MyLMU reads these files directly.
For the official in-game steps, see the Le Mans Ultimate Telemetry Recording guide.
Enable recording
Auto Record
- Open Le Mans Ultimate
- Go to Gameplay Settings
- Enable Auto Record for telemetry
Every session that supports telemetry will write a file automatically when you finish.
Manual hotkey
- Open Controls settings in LMU
- Bind a key to Record Telemetry
- Press the key during a session to start/stop recording
Steps and menu names can change with LMU updates — when in doubt, follow the official guide.
File location
Telemetry files are saved to:
...\UserData\Telemetry\
On Windows this is typically under your Steam library path for Le Mans Ultimate. Each file is a .duckdb database containing high-frequency channel data and session metadata.
File size guide
Duration drives file size. As a rough rule of thumb, a ~20 MB .duckdb is about a 15-minute recording. Shorter practice runs stay smaller; long races grow quickly (often tens of megabytes). Actual size varies with track, channels, and how much of the session was recorded.
On Free, the max upload is 20 MB — roughly that ~15-minute ballpark. See Free vs Pro.
Tips
- For useful analysis (and first try-outs), record at least one complete lap — out-lap-only or mid-lap cuts leave little for the track map, traces, and coach to work with
- Prefer a clean flying lap when you can; that gives clearer sector and ghost comparisons
- Use the same driver name in LMU as in MyLMU Settings for leaderboard eligibility
- Large sessions produce larger files — see Large file performance