How to Calculate Driving Cost per Mile: Formula, Worked Example & Price Tables

How to Calculate Driving Cost per Mile comes down to one division: cost per mile = tyre price ÷ expected mileage. A tyre that costs £130 as an example and lasts 30,000 miles costs 0.43 p per mile, and a set of four costs 1.73 p per mile. This page works the calculation out in full, shows the cost per mile for three example prices against three example mileages, and explains what moves the mileage — driving, alignment, pressure and load — and how to measure your own wear rate so the formula uses a real figure. Every price and mileage here is an example used to show the working; no tyre's real-world mileage is stated as fact.

On this page, how to calculate driving cost per mile is the case in point: The reason cost per mile matters is that the price on the shelf is not the price of using the tyre: a dearer tyre that lasts longer can cost less per mile than a cheap tyre that wears out quickly, and the only way to know is to divide the price by the mileage. The table below makes the pattern visible — the cost per mile falls as the mileage rises and rises as the price rises — and the sections after it cover the factors that decide the mileage, the method for measuring it, the common mistakes, and the other costs that make up the full cost of driving. All figures are examples with the assumptions stated next to them.

how to calculate driving cost per mile: The cost-per-mile formula

On this page, how to calculate driving cost per mile is the case in point: Cost per mile = tyre price ÷ expected mileage. For a single tyre, divide the price of one tyre by the miles it is expected to cover. For a set of four, the cost per mile is (4 × tyre price) ÷ expected mileage, which is four times the single-tyre figure. The result is usually expressed in pence or cents per mile: a tyre costing £130 over an assumed 30,000 miles gives £130 ÷ 30,000 = £0.0043, or 0.43 p per mile. The mileage in the formula is the uncertain half — it is an assumption or a measurement, never a guaranteed property of the tyre — so the worked example below states its assumptions plainly, and the section on measuring wear shows how to replace the assumption with a figure measured on the actual car.

how to calculate driving cost per mile: What cost per mile means

Taking how to calculate driving cost per mile as the case in point: The cost per mile of a tyre answers the question that the price tag does not: how much does each mile of use actually cost. A tyre that costs twice as much but lasts twice as long costs the same per mile, and a tyre that costs half as much but lasts a third as long costs more per mile. The formula is cost per mile = price ÷ expected mileage, and it is applied to one tyre at a time or to a set of four by multiplying the price by four. The figures in this article are examples with the assumptions stated next to them, because a tyre's real-world mileage is not a fixed property — it depends on how the car is driven, whether the alignment is right, whether the pressures are kept up, and what loads the tyre carries.

Worked example: £130 over 30,000 miles for how to calculate driving cost per mile

Taking how to calculate driving cost per mile as the case in point: Take a tyre priced at £130 as an example, with an assumed life of 30,000 miles. The cost per mile for one tyre is £130 ÷ 30,000 = £0.0043, which is 0.43 p per mile. A set of four costs £520 and lasts the same 30,000 miles, so the cost per mile for the set is £520 ÷ 30,000 = 1.73 p per mile. Over 10,000 miles of driving, the set costs 173.33 £ in tyre wear; over 12,000 miles a year it costs 208.00 £ a year. If the same tyre lasted 40,000 miles instead of 30,000, the cost per mile for the set would fall to 1.30 p; if it lasted only 20,000 miles, it would rise to 2.60 p. Both the price and the mileage are examples, labelled as such, and the mileage is the figure that matters most because it is the one that varies most between drivers.

Cost per mile table: three prices against three mileages for how to calculate driving cost per mile

Taking how to calculate driving cost per mile as the case in point: All prices and mileages are examples used to show the working. Read across for the mileage and down for the price.

Tyre price (example) 20,000 miles 30,000 miles 40,000 miles
£90 0.45 p per mile 0.30 p per mile 0.22 p per mile
£130 0.65 p per mile 0.43 p per mile 0.33 p per mile
£180 0.90 p per mile 0.60 p per mile 0.45 p per mile

For how to calculate driving cost per mile, the point is this: The table shows the two directions of the formula at once: moving right along a row, the cost per mile falls as the mileage rises, and moving down a column it rises as the price rises. A £90 tyre over 20,000 miles costs 0.45 p per mile, while the same tyre over 40,000 miles costs 0.22 p — the same tyre, the same price, and a very different cost per mile, decided entirely by how long it lasts. That is why the mileage deserves more attention than the price: it is the bigger lever, and it is the one the driver can influence by the way the car is driven and maintained. Compare tyres at the same assumed mileage so the comparison is like-for-like, and use a measured wear rate where one is available.

What decides how long a tyre lasts for how to calculate driving cost per mile

Taking how to calculate driving cost per mile as the case in point: Mileage is the uncertain half of the formula, and it is moved by several factors that are worth knowing before any comparison is made. Driving style matters most: hard acceleration, heavy braking and fast cornering wear the tread faster than smooth driving. Alignment matters next: a car that scrubs its tyres through a corner wears one edge of the tread and shortens the tyre's life. Inflation pressure matters too: under-inflation wears the shoulders and overheats the tyre, while over-inflation wears the centre. Load, road surface and temperature all play a part, and the tyre's own construction and compound set the starting point. Because so many factors move the mileage, the honest way to use the formula is with a mileage you have measured yourself — from the tread depth and the miles driven — rather than a figure quoted for the tyre.

how to calculate driving cost per mile: How to measure your own tyre mileage

On this page, how to calculate driving cost per mile is the case in point: The way to get a real mileage figure is to measure tread wear over a known distance. Record the tread depth with a gauge when the tyres are fitted and the odometer reading at the same time. After several thousand miles, measure again: the wear rate is the depth lost divided by the miles driven, and the remaining life is the depth left above the legal minimum divided by that wear rate. The legal minimum is 1.6 mm in the UK and 2/32 inch in the USA — jurisdiction-specific figures that change, so check the current limit where the car is used. That measured wear rate is the honest input to the cost-per-mile formula, and it is far more useful than any mileage quoted for the tyre, because it reflects the actual car, the actual driving and the actual roads.

Common mistakes with cost per mile for how to calculate driving cost per mile

For how to calculate driving cost per mile, the point is this: A few errors spoil cost-per-mile comparisons. One is judging tyres by the price on the shelf instead of the price per mile — the dearer tyre that lasts longer is often the cheaper one to run. Another is taking a mileage figure from a brochure or a review and treating it as a fact about the tyre on your car, when mileage depends on driving, alignment, pressure, load and roads. A third is leaving fitting and balancing out of the price, which flatters the result. A fourth is comparing tyres at different assumed mileages, which makes the cheaper per mile figure an artefact of the assumption rather than the tyre. And the last is forgetting that the per-mile figure is for one tyre: multiply by four for the set, and remember that tyres are only one part of the cost of running a car.

Related pages for how to calculate driving cost per mile

Frequently asked questions

How do I calculate how to calculate driving cost per mile?

Divide the tyre price by the expected mileage: cost per mile = price ÷ mileage. For a £130 example tyre over an assumed 30,000 miles, that is 0.43 p per mile for one tyre, or 1.73 p per mile for a set of four. The tyre cost per mile calculator runs the same formula with your own figures. That is the point this page works through for how to calculate driving cost per mile.

What is a good tyre cost per mile?

There is no single good figure, because it depends on the price and the mileage together. At the example figures on this page, a £130 tyre over 30,000 miles costs 0.43 p per mile for one tyre. Compare tyres at the same assumed mileage and judge the result against your own budget — and remember that the mileage is the figure that moves the answer most. That is the point this page works through for how to calculate driving cost per mile.

Does the price include fitting?

On this page, how to calculate driving cost per mile is the case in point: It should, if fitting, balancing and any disposal charge were part of what was paid. Leaving them out understates the true cost per mile, so add them to the price before dividing by the mileage. The worked example above uses the tyre price alone as an illustration, so add the fitting cost for a real figure.

How can I make my tyres last longer?

For how to calculate driving cost per mile, the point is this: Keep pressures at the placard figure, checked cold; have the alignment checked when the tyres show uneven wear; drive smoothly instead of accelerating hard and braking late; avoid overloading the car; and rotate the tyres if the manufacturer recommends it. Each of these extends the mileage in the formula, which cuts the cost per mile directly.

What is the legal minimum tread depth?

For how to calculate driving cost per mile, the point is this: In the UK the legal minimum tread depth is 1.6 mm across the central three-quarters of the tread, and in the USA it is 2/32 inch. Both are jurisdiction-specific limits and they change, so check the current figure where the car is used. Most drivers replace tyres before the legal minimum, because wet grip falls off well before the tread is bare.