Free calculator
Fuel margin calculator with card-fee and wet-stock allocation.
Grade inputs
Typical 0.005–0.010 (½ to 1 cent per gallon)
POS gallons − ATG inventory delta (positive = over-dispensed)
What you set at repricing (e.g. $0.18 = 18¢)
Realized margin
Normal gap (1–3¢/gal)
Typical realized-vs-target gap. Continue monitoring; no specific action needed unless the gap widens.
Realized = retail − wholesale − card fee − (wet-stock loss × cost ÷ gallons). California operators: prepaid SUT timing handled separately; this calculator covers the post-tax operating margin.
How this is computed.
Retail price per gallon.
Pump price at sale. If your shop reprices midday, use a weighted average across the period.
Wholesale cost per gallon.
Supplier cost at delivery. If wholesale moved during the period, use a weighted average by delivery date.
Card-processing fee per gallon.
Typically 0.5–1.0¢/gal. Your processor's fuel-specific rate; many independents have a flat fuel-fee structure.
Gallons sold.
POS-recorded gallons, reconciled against pump totalizer.
Wet-stock loss for the period.
(POS gallons − ATG inventory delta) × wholesale cost. If positive (more dispensed than expected), allocate to realized margin.
Realized margin per gallon.
Realized = retail − wholesale − card fee − (wet-stock loss / gallons sold).
Gap vs. target.
Gap = target − realized. Persistent gaps over 2¢/gal flag for investigation.
What the result tells you.
A 1–3¢/gal gap is typical. Anything above 4¢/gal on a sustained basis indicates a systemic issue, pump calibration drift, supplier cost mistracking, or wet-stock loss. Reproduce the calculation over multiple periods (week, month) to spot whether the gap is widening (pump drift) or stable (probably card-fee underestimation).
Use this when…
- Validating your monthly fuel margin against expected.
- Diagnosing why margin compressed without a wholesale move.
- Comparing realized margin across grades.
- Building the case for repricing or supplier negotiation.
Related.
Features
Buyer guides
From the blog
The forgotten margin is inside the store, not at the pump.
Fuel is a customer-acquisition cost. The actual margin lives in the inside-store revenue you capture from the customer who already parked. A field guide to pump-to-store conversion.
The fuel-margin math every operator should run weekly.
How to compute realized margin per grade, why it drifts from target, and the three reconciliation points (BOL, ATG, POS) that surface the leak before it compounds.
FAQs.
Where do I find my card-fee rate?
Your monthly merchant statement breaks it out per transaction type. Many processors charge a different rate for fuel-at-pump vs. inside-store. Use the fuel-specific rate (typically 0.5–1.0¢/gal).
How do I get wet-stock loss without ATG?
Manual tank-stick readings work. Read the tank at the start and end of the period; (start + deliveries − end) is your dispensed-from-tank number. Compare to POS gallons; the difference is wet-stock loss for the period.
Why doesn't this match the POS-reported margin?
POS-reported margin usually ignores card fees and wet-stock loss, both of which are real costs that reduce realized margin. This calculator includes them, which is why the realized number runs 1–3¢/gal below the POS-reported number.
See how StationPro automates fuel margin calculator.
Review your assumptions and the underlying workflow. We agree on the data and access needed before working with your store records.