Q. I don't know my cars mixed average MPG?
A. Then you need to know roughly how far your vehicle goes for say £10 of fuel, along with the cost per Litre (or Gallon). For example, firstly uncheck the 'Hold Consumption' tick box, set the spend at the pump to £10, set the cost per unit, in this case £1.11 per Litre, then enter the distance you know you normally get from such a pump spend (on average, mixed urban cycle and motorway/highway driving). If I enter 60 miles then this will calculate an MPG (and KMPL, mpl) value estimate of 30.35 MPG. Once the MPG is known then check the 'Hold Consumption' tick box to retain the MPG value (or it will change on the next calculation). Or try this dedicated simple mpg-calculator.

Q. I know my vehicle's rough mixed average MPG (or KMPL) and have a distance traveled but how much did it cost?
A. Enter or calculate the vehicles MPG (KMPL) value (see Q. above) say 30.35 MPG, set the nominal cost per unit of fuel (i.e. 1.11 per Litre), enter the distance traveled in KM or Miles, say 150 miles. The resultant spend at the pump value (of 25.00 in this case) is how much the fuel cost.

Q. Why is the 'True Cost per Mile' so high?
A. This is a yearly average calculation and requires costs and mileage entered for the year. If your annual mileage value is too small then the 'true cost per mile' will be exaggerated. Normally in the range 6000 to 12000 miles per year. If not known then you could estimate this based on weekly fuel spend x52 etc.

Q. Currency?
A. The calculator is not currency specific, you could enter all data in $ dollars, Euro's or whatever.

Q. UK gallons and US gallons are different?
A. Yes uncheck the 'UK' tick box next to the 'Gallons' textbox to use a US gallon conversion factor. Note that this requires an MPG recalculation based on new gallon measure.

Q. Why 2.30 KgCO2 per Litre?
A. That's an average starting point number for the amount of C02 produced when burning a litre of unleaded petrol (63% O2 taken from the air, hence so much weight). You will need to follow the links on the page to find more specific information about your vehicle and it's fuel burn characteristics.

Q. The Calculator doesn't fit on my screen?
A. Hold the Control key and spin the mouse wheel or manually set your browser's page zoom setting to suit. To reset the zoom press Ctrl+0 keys.

Q. How accurate are Calculator results?
A. Sadly there are some annoying rounding errors that occur (I'll try and fix them soon) but the results are close enough for a very good guide though it is not 100% accurate.

Q. Why did you bother to write this calculator?
A. Just for curiosity and a bit of fun, to hopefully make a useful tool for anyone for free. If you like the Calculator and find it useful then feel free to add a link to your website and pass the link on ;).

Q. Is it worth driving a few miles to get a couple of pence off a Litre? (aimed at UK motorists)
A. Well surprisingly (to me anyway) it's not worth it financially and can easily cost you money.
Say 2p a Litre discount for a 5 mile detour (2.5 mile each way) to buy £30 of fuel?
A regular family sized purchase... no you'd actually be loosing money!
With my car's 26.5 MPG I'd have to purchase £50-£60 worth of fuel to roughly break even on the deal.
Unless your able to buy huge amounts of fuel like a truck driver might, then you have to carry the weight of that fuel around. Petrol weighs ~0.75Kg/Litre. Personally I won't be swayed by a couple of pence here and there, if it requires any traveling to realise.

 

- You can change key calculator data to estimate budget costs for Petrol, Diesel, LPG, gasoline for trucks, vans, busses, pretty much any vehicle you like which consumes fuel.

- There are 3 custom memory slots to save and restore custom model setups into your browser's cookies. Makes it easier to compare custom setups with one click and save model setups for another day (valid until the year 2022). Note that the following link formats to the same page will save and restore different cookies (different domains): http://www.dhrc.rchomepage... or http://dhrc.rchomepage...

- If your Internet connection is not that reliable then you can always File->SaveAs this page to your hard drive and use a local copy when ever you like.

- How to save fuel? See these great fuel saving tips here. More useful information at whatprice.co.uk

UK Observations:

- A 1p increase a liter costs an extra ~£15 per year for an average 12,000 mile car owner. So avoid trying to drive too many miles to chance very small variations in fuel price.

- For £30 of fuel, a 1p increase a liter robs about 1.5 miles (at ~30 mpg), so if you have to make a detour (there and back) of 1.5 to 2 miles to get a 1p/liter lower fuel price then your saving nothing in fuel.

At 15p/m (at ~30mpg) fuel burn costs, £30 buys ~27 liter (at £1.11) so 1p/l buys an exrtra 27p of fuel which will only travel ~1.8 miles. Do a round trip futher than 1.8 miles to get the fuel and your loosing money!

eg. If your considering using a petrol station 7.5 miles out of your way, what price difference on £30 is worth traveling to get?
E.G. 2x 7.5 miles = 15 mile detour / 1.5miles (see above) = 10p/liter. So if you see a massive 10p/liter difference in price, even at 7.5 miles aways, if you only purchased £30 worth you would break even on the deal and waste time, wear and tear in your car for the privilege.

- Problems with metric Kg and Km? Try this online unit converter ;)