One mile is exactly 80 chains, so converting miles to chains is a single multiplication. Enter any figure and the result appears as you type — the arithmetic runs in your browser, so nothing is sent anywhere.
Sixty-six feet — the length of a cricket pitch, and the unit the US Public Land Survey was laid out in. The statute mile: 5,280 feet, used for road distance in the US, UK and a handful of others.
The mil and the millimetre are not the same thing and are out by a factor of about forty. A mil is one thousandth of an inch — 0.0254 mm — and a spec sheet that quotes film thickness in mils means the small unit. British drawings write the same size as "thou". The tables underneath give both a plain step-by-step lookup and a list of real quantities expressed in chains, so you can sanity-check whether your answer is a plausible size.
The formula
miles- The amount you are converting, in miles
80- The exact number of chains in one mile
chains- The converted result
How it works, step by step
- Enter the value in miles.
- It is multiplied by 80, the exact factor between the two units.
- The answer is shown in chains, with the reverse conversion beneath it.
- Check the reference table if you want a figure of comparable size.
Worked examples
The Eiffel Tower: 0.205 mi in chains
At 0.205 mi (the eiffel tower), the same quantity in chains is 0.205 × 80 = 16.4 ch. One mile is 80 chains, so the numbers grow as expected.
A marathon: 26.2 mi in chains
Take a marathon, roughly 26.2 mi. The conversion is a single multiplication — 26.2 × 80 — giving 2096 ch. Because the relationship is proportional, doubling the input doubles the answer to 4192 ch.
How to read your score
Frequently asked questions
How many chains are in one mile?
Exactly 80. Every figure on this page is that one number multiplied by your input, so the only rounding is at the display step.
What is the formula to convert miles to chains?
chains = miles × 80. Reversed, miles = chains ÷ 80, which is the same as multiplying by 0.0125.
Which is the bigger unit, the mile or the chain?
The mile. One mile equals 80 chains.
What does this quantity actually measure?
Both units measure length. That is why a single factor is enough: there is no temperature offset and no material property involved, unlike conversions that cross between different quantities.
What is a mile?
The statute mile: 5,280 feet, used for road distance in the US, UK and a handful of others.
What is a chain?
Sixty-six feet — the length of a cricket pitch, and the unit the US Public Land Survey was laid out in.
Why does my answer differ from another converter?
Almost always because the other tool rounded the factor before multiplying. This page keeps full double precision through the calculation and rounds only for display, and it prints the factor it used so you can see where any difference came from.
Miles to chains reference tables
| Miles | Chains |
|---|---|
| 0.5 mi | 40 ch |
| 1 mi | 80 ch |
| 2 mi | 160 ch |
| 3 mi | 240 ch |
| 5 mi | 400 ch |
| 10 mi | 800 ch |
| 20 mi | 1600 ch |
| 25 mi | 2000 ch |
| 50 mi | 4000 ch |
| 75 mi | 6000 ch |
| 100 mi | 8000 ch |
| 250 mi | 20,000 ch |
| 500 mi | 40,000 ch |
| 1000 mi | 80,000 ch |
| 5000 mi | 400,000 ch |
Exact factor: 1 mile = 80 chains.
| Quantity | mi | ch |
|---|---|---|
| A credit card’s long edge | 5.319e-05 mi | 0.004255 ch |
| A door height | 0.001263 mi | 0.101 ch |
| An Olympic pool | 0.03107 mi | 2.485 ch |
| The Eiffel Tower | 0.2051 mi | 16.4 ch |
| A marathon | 26.22 mi | 2098 ch |
| Earth’s diameter | 7918 mi | 6.334e+05 ch |
Published reference values, converted with the same factor this page uses.