Calculate exactly how much ethanol to add to your fuel tank to hit your target blend. Built for motorsport. Instant results. Zero guesswork — now right in your browser.
// features
Results update live as you move the sliders. No buttons to press, no forms to submit. The math runs on every keystroke — current blend, fuel volume, target percentage, done.
Metric and Imperial modes at a toggle. Whether you think in litres or gallons, E85 or pump 91, the calculator speaks your language without any settings menu.
Every ethanol percentage field has a synced slider and text box. Drag for speed, type for precision — both stay in sync. Fuel level accepts any decimal value.
Compiled straight to a Win32 executable in Go. No Python runtime, no .NET, no Electron. DPI-aware, ClearType fonts, dark title bar. Drop it anywhere and run.
// under the hood
Pure Go with direct Win32 syscalls. No GUI framework, no package bloat. A single self-contained PE32+ executable smaller than most phone photos. PerMonitorV2 DPI awareness and double-buffered GDI painting keep it crisp at any scale.
// windows download
Want it offline and in your tray at the track? Grab the native Windows build — one file, no installer, no admin rights.
