Google Maps Fuel Cost Calculator UK | Trip Planner

This calculator helps you estimate fuel costs for any journey across the UK. Start by entering your trip distance in miles. If you’re planning a route, check Google Maps or similar mapping services to find the exact distance between your starting point and destination.

Select your fuel type from the dropdown menu. The calculator supports petrol, diesel, premium petrol, and electric vehicles. Each fuel type has different pricing and efficiency characteristics that affect your overall journey cost.

Enter the current fuel price at your local station. Prices are typically displayed in pence per litre. For electric vehicles, enter the cost per kilowatt-hour (kWh) that you pay for charging. Home charging rates in the UK typically range from 20p to 30p per kWh.

Input your vehicle’s fuel efficiency. This can be found in your car’s manual, dashboard display, or manufacturer specifications. Choose the appropriate unit (MPG, MPL, or miles per kWh for electric vehicles) from the dropdown menu.

If you’re sharing the journey, enter the total number of passengers including yourself. The calculator will automatically divide the total cost among all passengers. Tick the “Return Journey” box if you’re calculating a round trip to double the distance automatically.

The calculator uses a straightforward formula based on distance, fuel efficiency, and current fuel prices. For petrol and diesel vehicles, it first converts your vehicle’s miles per gallon (MPG) to miles per litre (MPL) by dividing by 4.546, since one UK gallon equals 4.546 litres.

The fuel consumption is calculated by dividing the journey distance by your vehicle’s efficiency rating. For example, a 100-mile journey in a car achieving 45 MPG would require approximately 10 litres of fuel. The total cost is then determined by multiplying the fuel needed by the price per litre.

For electric vehicles, the calculation differs slightly. The energy consumption (in kWh) is determined by dividing the distance by the vehicle’s miles per kWh rating. This energy consumption is then multiplied by your electricity rate to give the total charging cost.

The cost per mile metric divides the total journey cost by the distance travelled, providing a useful benchmark for comparing different vehicles or fuel types. The per-person cost simply divides the total by the number of passengers, making it easier to split expenses fairly.

Plan Your Routes Efficiently: Combining multiple errands into one journey reduces overall fuel consumption. Cold engines use more fuel, so longer trips with a warmed-up engine are more efficient than several short journeys.

Monitor Fuel Prices: Use apps and websites that track local fuel prices. Prices can vary by 5-10p per litre between stations in the same area. Supermarket fuel stations typically offer competitive pricing, whilst motorway services charge premium rates.

Maintain Optimal Speed: On motorways, staying between 55-65mph provides the best fuel efficiency. Modern cars are typically most efficient at around 56mph in top gear. Every 5mph over 60mph reduces fuel economy significantly.

Reduce Vehicle Weight: Remove unnecessary items from your boot and consider removing roof racks when not in use. Every extra 50kg reduces fuel efficiency by approximately 2%.

Regular Maintenance: Keep your engine properly tuned with regular services. Clean air filters, proper oil levels, and correctly inflated tyres all contribute to better fuel economy. Check tyre pressure monthly, as under-inflation increases rolling resistance.

Smooth Driving Technique: Anticipate traffic flow to avoid harsh braking and acceleration. Use engine braking when approaching stops. Accelerate gently and change up through gears early to keep engine revs low.

If you drive your personal vehicle for business purposes, HMRC allows you to claim mileage expenses. The current approved mileage rates for 2025 are:

• Cars and vans: 45p per mile for the first 10,000 miles, then 25p per mile thereafter
• Motorcycles: 24p per mile
• Bicycles: 20p per mile

These rates cover fuel, insurance, road tax, and vehicle depreciation. You cannot claim actual fuel costs if you use the mileage rate. Keep accurate records of business journeys including dates, destinations, and purposes. Electric vehicle users claim the same rates despite lower running costs.

Beyond financial costs, consider the environmental impact of your journey. A typical petrol car emits approximately 180g of CO₂ per kilometre, whilst diesel vehicles emit around 160g per kilometre. Electric vehicles produce zero direct emissions, though electricity generation does create some emissions.

For a 100-mile journey, a petrol car emits roughly 29kg of CO₂, a diesel car about 26kg, and an electric vehicle produces zero tailpipe emissions. Carpooling significantly reduces per-person environmental impact – four people sharing one car is far more efficient than four separate journeys.

Public transport alternatives often provide lower emissions per passenger. Trains emit approximately 41g of CO₂ per passenger kilometre, whilst coaches emit around 27g. Consider these options for longer journeys where practical, especially for commuting or leisure travel.