To convert mils to rods, multiply by 5.050505051e-06. That factor is the whole relationship: both units measure length, so the conversion is a proportion with no offset and no substance-specific constant.
One thousandth of an inch, the standard thickness unit for plastic film and PCB traces. Sixteen and a half feet, or a quarter of a chain; it survives in old deeds and fence estimating.
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 rods, which is usually more useful than the bare number.
The formula
mils- The amount you are converting, in mils
5.05050505051e-06- The exact number of rods in one mil
rods- The converted result
How it works, step by step
- Enter the value in mils.
- It is multiplied by 5.05050505051e-06, the exact factor between the two units.
- The answer is shown in rods, with the reverse conversion beneath it.
- Check the reference table if you want a figure of comparable size.
Worked examples
A credit card’s long edge: 3370 mil in rods
At 3370 mil (a credit card’s long edge), the same quantity in rods is 3370 × 5.05051e-06 = 0.0170202 rd. One mil is 5.05051e-06 rods, so the numbers shrink as expected.
An Olympic pool: 1.97e+06 mil in rods
At 1.97e+06 mil (an olympic pool), the same quantity in rods is 1.97e+06 × 5.05051e-06 = 9.94949 rd. One mil is 5.05051e-06 rods, so the numbers shrink as expected.
How to read your score
Frequently asked questions
How many rods are in one mil?
Exactly 5.05050505051e-06. 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 mils to rods?
rods = mils × 5.05050505051e-06. Reversed, mils = rods ÷ 5.05050505051e-06, which is the same as multiplying by 198,000.
Which is the bigger unit, the mil or the rod?
The rod. One mil is only 5.05051e-06 of a rod, so it takes 198,000 mils to make one rod.
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 mil?
One thousandth of an inch, the standard thickness unit for plastic film and PCB traces.
What is a rod?
Sixteen and a half feet, or a quarter of a chain; it survives in old deeds and fence estimating.
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 mil to rd in my head?
Plenty of people do this in their head: divide by 200,000 instead of using the exact factor 0.000005. At 100 that shortcut gives 0.0005 rods, off by 0.000005 rods or about 1.00%. Fine for a rough estimate, not fine for anything you are cutting to size or dosing.
Mils to rods reference tables
| Mils | Rods |
|---|---|
| 0.5 mil | 2.52525e-06 rd |
| 1 mil | 5.05051e-06 rd |
| 2 mil | 1.0101e-05 rd |
| 3 mil | 1.51515e-05 rd |
| 5 mil | 2.52525e-05 rd |
| 10 mil | 5.05051e-05 rd |
| 20 mil | 0.00010101 rd |
| 25 mil | 0.000126263 rd |
| 50 mil | 0.000252525 rd |
| 75 mil | 0.000378788 rd |
| 100 mil | 0.000505051 rd |
| 250 mil | 0.00126263 rd |
| 500 mil | 0.00252525 rd |
| 1000 mil | 0.00505051 rd |
| 5000 mil | 0.0252525 rd |
Exact factor: 1 mil = 5.05050505051e-06 rods.
| Quantity | mil | rd |
|---|---|---|
| A credit card’s long edge | 3370 mil | 0.01702 rd |
| A door height | 8e+04 mil | 0.404 rd |
| An Olympic pool | 1.969e+06 mil | 9.942 rd |
| The Eiffel Tower | 1.299e+07 mil | 65.62 rd |
| A marathon | 1.661e+09 mil | 8390 rd |
| Earth’s diameter | 5.017e+11 mil | 2.534e+06 rd |
Published reference values, converted with the same factor this page uses.