v1.0.4 is live

Precision Meets Performance

The ultimate open-source vehicle performance timer. 10Hz GPS, Sensor Fusion, and a sleek companion app.

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Engineered for Accuracy

Advanced physics computations and hardware integration for the perfect run.

10Hz GPS: Parses raw NMEA sentences 10 times per second for pinpoint accuracy.
Sensor Fusion: Combines GPS data with a 20Hz accelerometer to reject multipath spikes.
Zero-Crossing Interpolation: Interpolates exact start times down to the millisecond.
Auto-Armed Launch: Starts recording exactly when you hit 3.0 km/h, bypassing GPS drift.

Interactive Slopes: Interactive charts mapped to your runs showing speed curves, G-force, and elevation slopes.
Fleet Management: Create and manage local profiles for all your vehicles to track performance independently.
Automated Weather: Automatically fetches ambient temperature and humidity for your location using Open-Meteo.
OLED Design & Wakelock: Stunning dark-mode app that intelligently keeps your screen on during active runs.

From a standstill to high-speed pulls, OpenDragy covers all your performance testing needs.

Drag Mode: 60ft, 330ft, 1/8 mile, 1000ft, 1/4 mile, 1/2 mile with trap speeds. (NHRA 1ft rollout and 66ft trap speed supported)
Metric Runs: 0–100 km/h, 100–200 km/h, 0-200 km/h.
Imperial Runs: 0–60 mph, 60–130 mph, 0–130 mph.
Custom Ranges: Define your own speed intervals in any unit.