IFTA Calculator
A free IFTA fuel tax calculator for carriers and owner-operators. Enter your miles and fuel purchases for each jurisdiction to estimate your quarterly IFTA tax, fleet MPG, and net taxable gallons — no spreadsheet required.
Tax rates change every quarter and differ by jurisdiction. Enter each state's current rate from the official IFTA tax rate matrix. This tool is an estimate — always verify with your base jurisdiction before filing.
Estimated IFTA tax due
$0.00
Enter miles and gallons for each jurisdiction to estimate your IFTA tax.
- Total miles
- 0
- Total gallons
- 0
- Fleet MPG
- —
How to calculate IFTA fuel tax
IFTA tax balances the fuel tax you paid at the pump against the fuel you actually burned in each jurisdiction. If you bought less fuel in a state than you used driving through it, you owe that state the difference; if you bought more, you get a credit. Here is the process:
1. Work out your fleet MPG
Add up the total miles driven across every jurisdiction and the total gallons of fuel purchased. Divide miles by gallons to get your average fleet miles per gallon for the quarter.
2. Find taxable gallons per jurisdiction
For each state, divide the miles you drove there by your fleet MPG. That is how many gallons you are deemed to have burned in that jurisdiction — its taxable gallons.
3. Subtract fuel already taxed
Subtract the gallons you bought in that jurisdiction (you already paid fuel tax at the pump) from its taxable gallons. The result is your net taxable gallons — positive means you owe, negative means a credit.
4. Apply each jurisdiction's tax rate
Multiply net taxable gallons by that jurisdiction's current tax rate, then add every jurisdiction together. The total is your net IFTA tax due or credit for the quarter.
Heads up: IFTA tax rates change every quarter and vary by jurisdiction. Always pull current rates from the official IFTA tax rate matrix and verify your figures with your base jurisdiction before filing.
IFTA calculator FAQ
Stop piecing together IFTA from receipts
DTV Soft tracks miles by jurisdiction and fuel purchases as you go, so your IFTA numbers are ready at the end of every quarter — no shoebox of receipts required.
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