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SAVINGS INTELLIGENCEby Secure Bytes Solutions LLC
TRUE TRIP COST · ORIGINAL GUIDE

A cheaper basket is not always a cheaper shopping trip.

Extra miles have a measurable fuel cost. Compare that cost to the potential savings at a farther store before leaving.

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The basic calculation

Extra fuel cost = additional round-trip miles ÷ vehicle miles per gallon × estimated fuel price per gallon. Compare the extra fuel against the savings on the basket itself. This simple model does not include travel time, wear, tolls, parking or changes in route traffic.

Example: a 12-mile detour

Illustrative numbers — not live station or grocery prices

Store A basket: $85.00. Store B basket: $78.00. Extra round-trip driving: 12 miles. Vehicle: 25 MPG. Assumed gas price: $3.50/gallon.

Fuel cost = 12 ÷ 25 × $3.50 = $1.68. Store B estimated total = $78 + $1.68 = $79.68. Store B is lower by $5.32, before taxes and other trip costs.

What the simple model cannot tell you

  1. Whether the advertised product will still be in stock.
  2. Whether a coupon or membership condition is actually eligible.
  3. Whether parking, tolls or time outweigh the saving.
  4. Whether a fuel station changed its price after the last observation.

Use estimates carefully

The public calculator uses values you type; it does not query HERE, Google, or any retailer. The developing desktop application has additional fuel intelligence, but evaluation data is not published to this website as a commercial price feed.