Hampton E85 Mix Calculator

Nail your ethanol blend every time.

Stop guessing at the pump. The Hampton E85 Calculator gives you the exact gallons of E85 and pump gas to add for any target ethanol blend — from E30 to E85.

Enter your tank size, current fuel level, and target mix Get precise fill amounts instantly See your estimated octane rating Works offline, no signal needed at the pump Fuel level helper estimates your tank from miles-to-empty Adjustable ethanol and octane defaults for your region Built by Hampton Tuning and real-world tested by enthusiasts. Whether you're on a flex fuel tune or dialing in a specific blend, this is the only tool you need at the pump.