Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Surcharge per mile
$0.092
Monthly surcharge recovery
$831
Price gap above baseline
$0.600
Gallons burned per month
1,385
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How to use this
- 1Enter current diesel price ($/gal).
- 2Enter contract baseline price ($/gal).
- 3Enter truck average mpg (mpg).
- 4Enter monthly miles (mi).
- 5Read your surcharge per mile on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
Fuel surcharges exist because base linehaul rates are negotiated assuming a baseline diesel price, and diesel doesn't sit still. This calculator computes the surcharge per mile you should charge (or receive) based on the gap between current diesel price and your contract's baseline price, factoring in your truck's average MPG. If your baseline is $3.50/gallon and diesel is now $4.30, at 6.5 MPG that's roughly $0.123 per mile you're leaving on the table if you don't apply a surcharge. Many carrier contracts use a published index (like DOE weekly retail diesel) with a surcharge table — this gives you the underlying math so you can verify what you're being paid matches reality.
Worked example
Using the values the calculator loads with:
Inputs
- Current diesel price: 4.1 $/gal
- Contract baseline price: 3.5 $/gal
- Truck average MPG: 6.5 mpg
- Monthly miles: 9000 mi
Results
- Surcharge per mile: $0.092
- Monthly surcharge recovery: $831
- Price gap above baseline: $0.60
- Gallons burned per month: 1,385
What each field means
Inputs
- Current diesel price ($/gal)
- The current diesel price used in the calculation, measured in $/gal. Starts at 4.1 $/gal so you have a working example on load.
- Contract baseline price ($/gal)
- The contract baseline price used in the calculation, measured in $/gal. Starts at 3.5 $/gal so you have a working example on load.
- Truck average MPG (mpg)
- The truck average mpg used in the calculation, measured in mpg. Starts at 6.5 mpg so you have a working example on load.
- Monthly miles (mi)
- The monthly miles used in the calculation, measured in mi. Starts at 9000 mi so you have a working example on load.
Results
- Surcharge per mile
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Monthly surcharge recovery
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Price gap above baseline
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Gallons burned per month
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Where does the baseline price come from?
It's set in your contract or broker agreement, usually referencing the DOE/EIA weekly national or regional average diesel price at the time the rate was negotiated. It should be stated explicitly in the rate confirmation — if it isn't, ask before hauling.
Why divide by MPG instead of just multiplying the price gap?
The surcharge needs to reimburse actual extra fuel spend per mile, not just the raw price difference. A truck at 6.5 MPG burns less fuel per mile than one at 5.5 MPG, so the dollar impact of a price jump differs by truck efficiency.
How often should surcharges update?
Most contracts update weekly off the published DOE index, lagged by a week or two. Diesel can swing 15-20 cents in a month, so a surcharge locked for a full quarter can badly under- or over-recover actual cost.
Does this apply to owner-operators under a carrier or independents?
Both — carriers pass fuel surcharge through to drivers under a percentage or per-mile split, and independents negotiate it directly with brokers or shippers. Either way the underlying math is the same gap-over-MPG calculation.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Fuel Surcharge Recovery Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/fuel-surcharge-recovery
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/fuel-surcharge-recovery" target="_blank" rel="noopener">Fuel Surcharge Recovery Calculator — RevenueLab</a> (2026).</p>
Source: [Fuel Surcharge Recovery Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/fuel-surcharge-recovery) (2026).