Why does each segment have its own MPG value?

Fuel economy varies with driving conditions. A motorway cruise may achieve 45 MPG, while urban stop-and-go traffic in the next segment might drop to 32 MPG. Entering separate MPG figures for each leg produces a more accurate total cost estimate than assuming one average across the entire trip.

Can I enter distances in kilometres instead of miles?

This calculator accepts distance in miles and fuel economy in miles per UK imperial gallon. To use kilometres, convert distance to miles (km ÷ 1.609344) and fuel economy to MPG (L/100 km can be converted via MPG ≈ 282.48 ÷ L/100 km for UK gallons) before entering the values.

What if I only need two segments?

Leave Segment 3 distance at zero. The engine filters out any segment with distance or MPG of zero, so only the segments with positive distance and MPG contribute to the total cost. The tool will display the count of active segments in the results.

Does the calculator include return-journey fuel?

No. Each segment represents a one-way leg. To estimate a return trip, either double the final total cost (if conditions are symmetric) or enter each return leg as additional segments with appropriate distances, MPG, and fuel prices for the homeward route.

How accurate is the average cost per mile figure?

The average cost per mile is total fuel cost divided by total distance. Its accuracy depends entirely on the accuracy of the MPG and price-per-litre inputs. If actual fuel economy differs from the entered values—due to weather, load, or driving style—the per-mile figure will differ proportionally.

Fuel & Efficiency

Multi-Stop Fuel Cost Calculator

Calculate total fuel cost across up to three road-trip segments with different MPG and fuel prices.

Last updated: 25 June 2026

What this tool does

This calculator computes the total fuel cost for a road trip divided into up to three segments, each with its own distance, fuel economy (MPG), and price per litre. For each segment, the engine converts distance and MPG into litres consumed (using the UK imperial gallon constant 4.54609 L/gal), multiplies by the local fuel price, then sums the results. Secondary outputs include total distance, total fuel consumed, average cost per mile, and the number of active segments entered.

Inputs

Result

—

Formula

C_{total} = i = 1 \sum n d_{i} \times \frac{4.546}{m _{i}} \times p_{i}

C_{total}

Total fuel cost (£)

d_{i}

Segment i distance (miles)

m_{i}

Segment i fuel economy (MPG)

p_{i}

Segment i fuel price (£/L)

n

Number of segments

4.546

Litres per UK gallon

How Multi-Stop Fuel Cost Calculator works

This calculator splits a road trip into up to three distinct segments. Each segment accepts its own distance (miles), fuel economy (miles per UK imperial gallon), and fuel price (pounds per litre). The engine computes the litres consumed in each segment by dividing distance by MPG and converting to litres using the UK gallon factor 4.54609. It then multiplies litres by the local price, sums all segment costs, and returns the total trip fuel expenditure plus distance, volume, and per-mile averages.

The formula

For each segment i:
Litres_i = (Distance_i ÷ MPG_i) × 4.54609
Cost_i = Litres_i × Price_i

Total cost = Σ Cost_i across all segments with Distance > 0 and MPG > 0. Average cost per mile = Total cost ÷ Total distance.

Where this method is most accurate

The calculation assumes the entered MPG figures are accurate for the driving conditions (motorway, urban, laden weight) of each segment. Fuel economy can vary significantly with speed, traffic, terrain, and temperature. The tool also assumes refuelling occurs at the entered price per litre; actual pump prices fluctuate hourly. Results are most reliable when MPG values come from recent trip-computer readings under similar conditions.

What this tool does not do

This calculator does not predict future fuel prices, account for detours or traffic delays, include non-fuel costs (tolls, parking, meals), or adjust for hybrid/electric regeneration. It does not verify whether a given MPG is achievable for a specific vehicle or driving style. The output is a mathematical projection based solely on the inputs entered, not a guarantee of actual expenditure.

Disclaimer

This tool is provided for educational and informational purposes only. It does not constitute financial advice, vehicle purchasing guidance, or a recommendation to undertake any particular journey. Actual fuel consumption and costs will vary. Users remain responsible for verifying all inputs and for decisions made using the results.

Questions

Why does each segment have its own MPG value?: Fuel economy varies with driving conditions. A motorway cruise may achieve 45 MPG, while urban stop-and-go traffic in the next segment might drop to 32 MPG. Entering separate MPG figures for each leg produces a more accurate total cost estimate than assuming one average across the entire trip.
Can I enter distances in kilometres instead of miles?: This calculator accepts distance in miles and fuel economy in miles per UK imperial gallon. To use kilometres, convert distance to miles (km ÷ 1.609344) and fuel economy to MPG (L/100 km can be converted via MPG ≈ 282.48 ÷ L/100 km for UK gallons) before entering the values.
What if I only need two segments?: Leave Segment 3 distance at zero. The engine filters out any segment with distance or MPG of zero, so only the segments with positive distance and MPG contribute to the total cost. The tool will display the count of active segments in the results.
Does the calculator include return-journey fuel?: No. Each segment represents a one-way leg. To estimate a return trip, either double the final total cost (if conditions are symmetric) or enter each return leg as additional segments with appropriate distances, MPG, and fuel prices for the homeward route.
How accurate is the average cost per mile figure?: The average cost per mile is total fuel cost divided by total distance. Its accuracy depends entirely on the accuracy of the MPG and price-per-litre inputs. If actual fuel economy differs from the entered values—due to weather, load, or driving style—the per-mile figure will differ proportionally.

Spotted something off?

Calculations or display — let us know.

Sources & Methodology

For each segment, the calculator divides distance (miles) by fuel economy (MPG UK imperial) and multiplies by 4.54609 litres per UK gallon to obtain litres consumed, then multiplies by the price per litre. Segment costs are summed to produce total trip fuel cost. The UK gallon conversion factor is defined by UK Weights and Measures Act 1985.

Related tools

Fuel Cost for a Journey

Calculate the total fuel cost for a journey from distance, MPG, and fuel price per litre.

MPG Converter (UK/US/L per 100km)

Convert fuel economy between imperial MPG, US MPG, and liters per 100 km with precise gallon conversions.

Fuel Needed for Journey

Calculate liters, imperial gallons or US gallons of fuel needed for any journey distance and vehicle MPG.

Tank Range Calculator

Calculate your vehicle's maximum driving range from tank size and fuel economy.

MPG Improvement Savings Calculator

Calculate annual fuel savings from improved miles-per-gallon efficiency.

Annual Fuel Cost Projector

Calculate your yearly petrol or diesel spend from annual miles, MPG and pump price.

People also use

Monthly Car Payment Calculator

Financing & Purchase

Calculate your monthly car loan payment from loan amount, APR, and term in months.

Loan vs Lease Comparison

Cost of Ownership

Compare total cost of buying on finance versus leasing over different terms and buyout scenarios.

EV vs Petrol Total Cost (5yr)

EV vs ICE

Compare total cost of ownership—purchase price, fuel, and depreciation—for EV vs petrol over 1–20 years.

Braking Distance Calculator

Performance & Engineering

Calculate total stopping distance from speed, road friction and driver reaction time.

Long Road Trip Total Cost

Practical & Utility

Calculate total fuel, lodging, food, and toll expenses for a multi-day road trip.

Depreciation % Retained Calculator

Resale & Depreciation

Calculate what percentage of its original value a car has retained after depreciation.