Flex fuel ethanol calculator
Fuel| Gasoline ethanol content % |
| E85 ethanol content % |
| Fuel tank size gallons |
| Current fuel level % |
| Current ethanol content % |
| Desired ethanol content % |
| Fuel to add gallons |
| E85 gallons |
| Gasoline gallons |
| Final ethanol % |
This calculates what blend of gasoline and E85 you need in order to get the right ethanol content in you tank.