Mileage Calculator

This page holds two mileage tools. The first works out the driving distance and time by car between two places, disregarding traffic. The second turns a pair of odometer readings into a trip distance and a reimbursement figure, which is the version you want for an expense claim.

Driving distance is not straight-line distance

Roads do not go where a ruler does. New York to Boston is 190 miles as the crow flies and about 214 by road, a detour factor of roughly 1.12. That ratio varies enormously with terrain: it is close to 1.05 across a flat grid-planned state and can exceed 2 where a mountain range, a lake or a coastline forces a long way round.

This is why a mileage claim should never be estimated from a map's scale bar, and why a distance calculator that returns great-circle distance is the wrong tool for anything involving a vehicle. The calculator above asks a routing engine for an actual road route.

Why two routing engines disagree

Run the same journey through different services and the answers will differ slightly, for three reasons.

Route choice. Engines weigh distance against expected speed differently, so one picks the interstate and another shaves two miles off through a town. On New York to Boston the difference here comes to about half a percent, which is 214 miles against 215.

Speed assumptions. Distance is close to objective; time is a model. The engine behind this page applies conservative free-flow speeds from the road classification, which produces a longer estimate than services calibrated against millions of recorded journeys. Expect the time here to run high on long motorway trips, and treat it as an upper bound for an unhurried drive rather than a prediction.

Traffic. Neither figure on this page accounts for traffic at all, which is the same basis their calculator states. A commute at eight in the morning bears no relation to the same road at midnight, and only a live traffic model captures that. The link under the result opens the route in Google Maps if you need the current picture.

Mileage reimbursement

The second tool exists because most people looking up mileage are doing so to get paid for it. Take the odometer reading at the start and the end, subtract, and multiply by the rate.

In the United States the IRS publishes a standard mileage rate each year, which is why the calculator defaults to a rate rather than a fuel price. The business rate was 70 cents a mile for 2025. It is revised annually and the charitable rate, fixed in statute at 14 cents, moves only if Congress changes the law. Medical and moving mileage is set separately and is much lower than the business rate. Check the current year's figures with the IRS before filing.

The standard rate is not a fuel allowance. It is meant to cover the whole cost of running the vehicle for those miles: fuel, oil, tires, servicing, repairs, insurance, registration and depreciation. That is why it sits far above the fuel cost alone, and why claiming the standard rate and then separately claiming fuel would be claiming the same expense twice.

Standard rate or actual costs

The alternative is the actual expense method: total up what the vehicle really cost over the year and claim the business-use percentage of it. Actual costs usually win for expensive vehicles, heavy depreciation and low mileage. The standard rate usually wins for high mileage in a cheap, reliable car, and it wins on paperwork every time, since it needs a mileage log rather than a shoebox of receipts.

There is a catch worth knowing before choosing. If you want the option of switching methods later, the standard rate generally has to be used in the first year the vehicle is in service. Start with actual expenses and the standard rate may be closed to you for that vehicle.

What a compliant log looks like

Tax authorities want contemporaneous records rather than a reconstruction at year end. For each trip, note the date, the starting point and destination, the business purpose, and the miles driven. Record the odometer at the start and end of the year as well, so total mileage and business mileage can both be shown.

Commuting between home and a regular workplace is not deductible business mileage in the United States, however far it is. Travel between two work locations, out to a client, or from a home office that is your principal place of business generally is. That distinction accounts for more rejected claims than any arithmetic error.

Two odometer readings, one caveat

Odometers are accurate enough for this and are not perfect. Regulations in most countries allow a tolerance of a few percent, and readings drift with tire size: fitting larger-diameter tires makes the odometer under-read, because the wheel covers more ground per revolution than the vehicle was calibrated for.

For a mileage claim it hardly matters, since the odometer is the accepted record. For measuring fuel economy it matters more, because the error feeds straight into miles per gallon.

Getting a good answer from the place lookup

Place names go to OpenStreetMap, so a city, a full street address, a postcode or a well-known landmark all resolve.

Ambiguity is the usual failure. There are around thirty places called Springfield in the United States, and a bare city name gets you whichever one the geocoder ranks first. Adding the state or the country fixes it: "Springfield, IL" and "Springfield, MA" are 1,000 miles apart and the calculator has no way of guessing which you meant. The resolved place names are printed with the result so you can check it picked the right one.

For an exact figure, use full addresses rather than city names. City to city routes to a nominal centre point, which can be a mile or two from the address you actually mean.

Putting the two tools together

The two halves of this page answer different questions about the same drive, and running them side by side is where the numbers get interesting.

Take New York to Boston at 214 miles. A car returning 30 mpg burns 7.13 gallons, which at $3.20 a gallon is $22.83 of fuel each way, or $45.65 for the round trip. Claimed at the 70 cent standard rate, the same one-way drive is worth $149.80.

That gap, roughly six and a half times the fuel cost, is not a windfall. It is the standard rate doing what it is designed to do: covering tires, servicing, insurance, registration and above all depreciation, which is the largest cost of running a car and the one nobody feels until they sell it. Fuel is the visible cost and rarely the biggest.

It also explains why the two methods diverge so sharply for different drivers. Someone putting 25,000 business miles a year on an old, cheap, economical car does very well from the standard rate. Someone driving 3,000 miles in a new car losing value quickly may do better counting actual costs.

Common mistakes

The first is using straight-line distance for a vehicle journey. Expect roughly 10% to 25% more by road in ordinary terrain, and considerably more where geography intervenes.

The second is treating the driving time as a schedule. It is a free-flow estimate with no traffic, no fuel stops, no roadworks and no lunch. Real journeys take longer, and the estimate here is deliberately not a promise.

The third is claiming both the standard mileage rate and fuel receipts. The rate already includes fuel, along with everything else the vehicle costs to run.

The fourth is a mileage log written from memory in April. Contemporaneous records are the standard, and a reconstructed log is the first thing an auditor discounts.

The fifth is claiming the commute. Home to a regular workplace does not count, no matter how long the drive is.