How many feet are in one mile?

The answer to the question is far more complicated than one might think. I have fairly frequently heard in the US the same question as this topic, and often the recipient will ask for a clarification as to what kind of mile—like statute or nautical—to which the original questioner would typically respond, “Yeah, you know, the statute mile like we use on land.” Typically neither the requester nor the responder actually realizes the consequences of how the clarification question is answered.

In the United Kingdom it is easy: 1 mi = 5280 ft (by definition, so exact).

In the United States, there are two kinds of miles and two kinds of feet that are relevant to this question. For both miles and feet, there is a pair of international units and a pair of survey units. Up to 1959–06–30, there was only one legal foot in the USA, whose length was equal to (1200/3937) m (technically the yard was (3600/3937) m, the foot was 1/3 of that yard and the inch was 1/36 of that yard—the intent was to make the inch such that 1 m =39.37 in, as Americans had a propensity to try to make the metric units look like they were defined in terms of American units, making it easier for Americans to convert metric measurements to US customary units). Vladimir mentioned in his answer a 1593 act of Parliament that in essence set the mile equal to 5280 ft; this mile ended up being called a statute mile because it was defined by a legal statute. The US had the same relationship between the statute mile and the foot, namely a factor of 5280.

The first problem was that the US and the English-speaking members of the British Commonwealth of Nations (UK, Canada, Australia, New Zealand, and South Africa) had different definitions of the yard—the US in terms of the meter and most commonwealth countries having a metal bar artifact, except Canada had defined the foot to be 0.3048 m (a different relation to the meter than the US). This mismatch was regarded as undesirable and representatives from these countries agreed in 1959 to define the yard as 0.9144 m, so the foot became 0.3048 m, matching Canada’s already existing definition, shortened the US definition by exactly 2 parts per million, and lengthened the UK foot by a bit. The UK adopted this new definition and applied it to all derived units, including the acre as land area, effective 1964–01–01. The US adopted the new definition immediately and applied it to all derived units (including volume measures such as gallon) that were not associated with land measurement. (Thus the UK acre changed with the change of the yard but the US acre did not; the US gallon defined as 231 in³ changed with the change of the yard, but the UK gallon defined as the volume of 10 lb of distilled water at certain specified conditions did not.) The problem in the US was the existence of huge amounts of survey data that were based on the pre-1959 foot; though 2 parts per million change sounds small, it becomes very difficult to realign data points that are hundreds of miles apart. Therefore, the US retained the old foot, renaming it appropriately to “survey foot”, for anything related to survey maps and data. This meant that the rod, furlong, fathom (water depths showing up on maps), statute mile, and acre retained their pre-1959 size, and the statute mile stayed at 5280 survey-feet. The post-1959 foot became known as simply the foot (thus use of “foot” unmodified defaults to meaning the post-1959 foot of 0.3048 m); however, if there was any risk of ambiguity, the new foot would be referred to explicitly as the “international foot”. Thus, nominally (more about this weasel word later) 1 statute mile is:
exactly 5280 survey feet and
exactly [(5280 × 1200 / 3937) / 0.3048] feet, which is approximately 5280.010 56 feet.

Now, there was also an adjustment to the mile to keep its relation to the adjusted foot with the factor 5280. This mile is known more explicitly as the “international mile” in parallel with the foot. There are 4 names for “land” miles (not counting nautical miles and some other really obscure miles): mile, international mile, statute mile, survey mile—the first two are synonymous with each other. Now it gets really complicated. The United States is a federal system, meaning the national (usually called federal) government has authority over all commerce (which includes weights and measures) that crosses state borders, whereas each state has authority for activities within the confines of the state. At the federal level and within most states the statute mile is synonymous with the survey mile, but supposedly in eight states all length/area/volume measurements have been adjusted to conform to the post-1959 definition of the yard and foot, so that the statute mile is synonymous with the international mile (and the acre is 4640 yd², not 4640 survey-yd²).

The bottom line is:
1 mi = 5280 ft = 1609.344 m (exactly) in all jurisdictions of the US;
1 st mi = 5280 survey-ft = 5280.010 56… ft = 1609.3472… m at the national level and in most states,
…………. 5280 ft = 1609.344 m in a few states.
It is because of the two different values here for “the” statute mile that triggered my used of “nominally” earlier in this post and that I would have more about this—well, here it is. The use of “nominally” is because it is the definition and value used by the National Institute of Standards and Technology and most, but not all, states have adopted.

Most people do not care about this small of a difference—they would never notice. However, definitions need to be set up so that one definition covers everybody, including researchers and makers of precision equipment for whom this is a big difference as well as the common folk who do not care at all. I have actually worked in an application where the distinction between an international mile and the survey mile came up because an important error showed up in a simulation that mixed up the conversion factors between survey units versus international units and metric units.

For the life of me I do not understand why so many Americans fight so hard to retain use of the US customary units and resist using metric units. They talk about how hard the metric system is and how easy to deal with the American units. When they do, I cannot help but think about issues with the number of feet in a mile, avoirdupois ounces versus troy ounces versus fluid ounces, how big is a bushel (which varies from state to state and commodity to commodity and often has little to do with the NIST definition), and numerous other oddities that make me wonder how anybody can think this is easier than the metric system. Then I remember Americans do not care enough—they live in blissful ignorance having a hard time remembering how many inches are in a yard and most really do not care that they do not know. It is very sad.

Although I’d like to follow HTD (How To Discuss?) guidlines and simply answer this, it’s apparent you aren’t using your resources correctly, Mr Anonymous.
A quick check at Google with “miles to feet” would tell you faster, and avoid us from checking your history.
My biggest concern, with all niceness and respect, is that you’re not listening and learning in the classroom.
“Much” involves how much stuff. “How much dirt did my Dog just dig in my neighbor’s yard?” I don’t care about cubic feet, just wanna know how long it’ll take.
“Many” is a number… How many minutes should it take to repair the lawn…
In addition, “miles” ain’t OK. How many feet depends on the miles thing…How many?
“How many feet “ARE” in a MILE.”
BTW, I learned in early elementary school, listened, and remembered 60 years…
5280. You’re welcome. I’ll go back to reading and answering questions which involve my experience…

TL; DR - 5280 feet

For the rigorous minded folks -

Well, let’s see

1 feet = 12 inch
1 inch = 2.54 centimeters
So, 1 feet = 30.48 cms = 30.5 cms approximately
Therefore, 1 meter = 3.28084 feet

Now 1 mile = 1.60934 kilometers = 1609.34 meters

Combining both results, we get the required answer which is 1 mile = 5280 feet