Guides
What is a .vbo file?
A .vbo file is Racelogic's GPS data logging format: a plain-text file containing a header, a list of channel names, and rows of timestamped samples covering position, speed, heading, altitude and satellite count. It originated with VBOX hardware and has become the common interchange format for track-day data, which is why RaceChrono and Dragy both export to it.
The format in one paragraph
A .vbo file is a plain-text GPS log. It was created by Racelogic for their VBOX range and has since become the closest thing track-day data has to a universal format. Open one in a text editor and you will find a header block with metadata, a [column names] section listing the channels, and a [data] section of rows, one per sample.
Because it is readable text and widely supported, other manufacturers export to it too. RaceChrono Pro can write one, Dragy’s app can write one, and most analysis and overlay software can read one.
What is inside
The standard channels you will find in almost any VBO:
| Channel | Meaning |
|---|---|
sats |
Number of satellites in use, plus flag bits |
time |
UTC time since midnight, as HH:MM:SS.SS |
lat |
Latitude in minutes, positive is North |
long |
Longitude in minutes, positive is West |
velocity |
Speed in km/h |
heading |
Degrees relative to north |
height |
Metres above sea level, WGS84 |
vertical velocity |
km/h, positive uphill |
Loggers commonly add their own channels beyond these: lap number, sector times, accelerometer axes, OBD-II data. Software that does not recognise a channel simply ignores it, so extra columns are harmless.
The two things that catch people out
Positions are in minutes, not decimal degrees. A latitude of 03119.09973 is not 3,119 degrees. It reads as 31 degrees, 19.09973 minutes, which resolves to 51 degrees, 59 minutes, 5.9838 seconds once converted. If you import a VBO into a spreadsheet and plot it raw, the track will be nowhere near where you drove.
Positive longitude means West. This is the opposite of the convention almost everything else uses, where East is positive. A session in continental Europe will have a negative longitude in a VBO, and mirroring the sign without thinking will place it in the Atlantic.
The sats column carries flags. The satellite count has bits added to it: 64 when the brake trigger input is active, and 128 when the unit is applying a DGPS correction. So sats = 138 means ten satellites with DGPS applied, not a hundred and thirty-eight satellites in view.
How to get one
- VBOX Motorsport hardware writes
.vbonatively, so copy it from the unit’s storage. See using a VBOX session as an overlay. - RaceChrono Pro: Lap times, then Options, Export laps, and set Type to VBox (.vbo). See the full export walkthrough.
- Dragy: export the session from the app in VBO form. See using Dragy data.
What you can do with one
Analysis tools such as Racelogic’s Circuit Tools read VBO for speed traces and lap comparison. Overlay tools read it to draw the data onto video.
TrackHero parses VBO directly in the browser: load the file with your onboard video and it renders speed, G-force and lap-delta gauges into a finished MP4, free, with nothing uploaded.
Last updated .