One chain is exactly 57,024 points, so converting chains to points 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 DTP point: exactly 1/72 inch, the unit type size is set in.
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". Two tables follow: rounded steps for quick lookup, and a set of real reference quantities converted into points, which is usually more useful than the bare number.
The formula
chains- The amount you are converting, in chains
57,024- The exact number of points in one chain
points- The converted result
How it works, step by step
- Enter the value in chains.
- It is multiplied by 57,024, the exact factor between the two units.
- The answer is shown in points, with the reverse conversion beneath it.
- Check the reference table if you want a figure of comparable size.
Worked examples
Earth’s diameter: 6.33e+05 ch in points
At 6.33e+05 ch (earth’s diameter), the same quantity in points is 6.33e+05 × 57,024 = 3.60962e+10 pt. One chain is 57,024 points, so the numbers grow as expected.
A credit card’s long edge: 0.00426 ch in points
A credit card’s long edge comes to about 0.00426 ch. Multiplying by the factor: 0.00426 × 57,024 = 242.922 pt. Dividing the answer back by 57,024 returns the figure you started with, which is the quickest way to check you have the factor the right way up.
How to read your score
Frequently asked questions
How many points are in one chain?
Exactly 57,024. 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 chains to points?
points = chains × 57,024. Reversed, chains = points ÷ 57,024, which is the same as multiplying by 1.75364758698e-05.
Which is the bigger unit, the chain or the point?
The chain. One chain equals 57,024 points.
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 chain?
Sixty-six feet — the length of a cricket pitch, and the unit the US Public Land Survey was laid out in.
What is a point?
The DTP point: exactly 1/72 inch, the unit type size is set 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.
Is there a quick way to do ch to pt in my head?
Plenty of people do this in their head: multiply by 57,000 instead of using the exact factor 57,024. At 100 that shortcut gives 5,700,000 points, off by 2400 points or about 0.04%. Fine for a rough estimate, not fine for anything you are cutting to size or dosing.
Chains to points reference tables
| Chains | Points |
|---|---|
| 0.5 ch | 28,512 pt |
| 1 ch | 57,024 pt |
| 2 ch | 114,048 pt |
| 3 ch | 171,072 pt |
| 5 ch | 285,120 pt |
| 10 ch | 570,240 pt |
| 20 ch | 1.14048e+06 pt |
| 25 ch | 1.4256e+06 pt |
| 50 ch | 2.8512e+06 pt |
| 75 ch | 4.2768e+06 pt |
| 100 ch | 5.7024e+06 pt |
| 250 ch | 1.4256e+07 pt |
| 500 ch | 2.8512e+07 pt |
| 1000 ch | 5.7024e+07 pt |
| 5000 ch | 2.8512e+08 pt |
Exact factor: 1 chain = 57,024 points.
| Quantity | ch | pt |
|---|---|---|
| A credit card’s long edge | 0.004255 ch | 242.6 pt |
| A door height | 0.101 ch | 5760 pt |
| An Olympic pool | 2.485 ch | 1.417e+05 pt |
| The Eiffel Tower | 16.4 ch | 9.354e+05 pt |
| A marathon | 2098 ch | 1.196e+08 pt |
| Earth’s diameter | 6.334e+05 ch | 3.612e+10 pt |
Published reference values, converted with the same factor this page uses.