How E10 vs E85 Fuel Cost Calculator Works?
This tool works by subtracting the E10 cost per mile from the E85 cost per mile and multiplying by 10,000 miles. The result shows which fuel costs less across 10,000 miles (16,093 km).
Find the E10 cost per mile
Divide the E10 price by E10 miles per gallon (MPG). $3.60 ÷ 28 MPG = $0.128 per mile.
Find the E85 cost per mile
Divide the E85 price by E85 MPG. $2.85 ÷ 21 MPG = $0.135 per mile.
Enter both costs per mile
Put the E10 figure first and the E85 figure second.
Read the 10,000-mile delta
A positive result means E85 costs more. A negative result means E85 costs less.
E10 vs E85 Fuel Cost Calculator Formula
The formula is Cost Delta = (E85 Cost per Mile − E10 Cost per Mile) × 10,000.
Cost Delta = (E85 $/mi − E10 $/mi) × 10,000 milesFormula variables
- E10 $/mi
- Cost per mile on gasoline with up to 10% ethanol.
- E85 $/mi
- Cost per mile on flex fuel with 51% to 83% ethanol.
- 10,000
- Fixed comparison distance in miles.
Worked example
- E10 Standard (28 MPG @ $3.60): $0.128/mi
- E85 Flex Fuel (21 MPG @ $2.85): $0.135/mi
- Per-mile gap: $0.135 − $0.128 = $0.007.
- Delta: $0.007 × 10,000 = $70.00 extra on E85.
Result: $70.00 ($ cost delta)
Flex-fuel vehicles get 15% to 27% fewer miles per gallon on E85, according to the US Department of Energy (DOE). E85 saves money only when the pump price is lower by a larger percentage than the MPG loss.
E10 vs E85 Fuel Cost Calculator Conversion Table
The table shows the 10,000-mile cost delta for 3 E10 costs per mile and 3 E85 costs per mile. Negative values mean E85 is cheaper.
Rows: E10 Standard (28 MPG @ $3.60) ($/mi). Columns: E85 Flex Fuel (21 MPG @ $2.85) ($/mi). Cells: $ cost delta.
| $/mi | $0.12/mi | $0.135/mi | $0.16/mi |
|---|---|---|---|
| $0.11/mi | $100.00 | $250.00 | $500.00 |
| $0.128/mi | -$80.00 | $70.00 | $320.00 |
| $0.15/mi | -$300.00 | -$150.00 | $100.00 |
E85 at $0.12 per mile saves $300.00 over 10,000 miles against E10 at $0.15 per mile.
What is E10 vs E85 Fuel Cost Calculator?
The E10 vs E85 Fuel Cost Calculator is a tool that compares the cost of driving a flex-fuel vehicle (FFV) on E10 gasoline and on E85 ethanol. The tool shows which fuel is cheaper per mile.
E10 is regular US gasoline with up to 10% ethanol. E85 is a high-ethanol blend sold mostly in the Midwest. E85 costs less per gallon but holds less energy, which lowers MPG.
Comparing cost per mile, not cost per gallon, removes the MPG difference and gives a fair answer.
What are the uses of E10 vs E85 Fuel Cost Calculator?
There are 4 main uses of the E10 vs E85 Fuel Cost Calculator: choosing fuel for a flex-fuel vehicle, checking E85 deals, comparing regional prices, and planning fleet fuel purchases.
Choosing fuel for a flex-fuel vehicle
FFV owners pick the cheaper fuel at each fill-up.
Checking E85 deals
Drivers test whether a low E85 price beats E10 after MPG loss.
Comparing regional prices
Midwest drivers compare E85 prices across stations.
Planning fleet fuel purchases
Government fleets with FFVs compare fuel costs per mile.
Need every metric in one place? Open the main MPG Cost Calculator or browse all 101 fuel calculators.