This page converts millimeters into rods using the factor 0.0001988387815, and shows the reverse figure alongside it. Both units measure length, which is why one number does the whole job.
Sixteen and a half feet, or a quarter of a chain; it survives in old deeds and fence estimating. One thousandth of a metre — the finest gradation on a standard ruler.
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
millimeters- The amount you are converting, in millimeters
0.000198838781516- The exact number of rods in one millimeter
rods- The converted result
How it works, step by step
- Enter the value in millimeters.
- It is multiplied by 0.000198838781516, 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
The Eiffel Tower: 3.3e+05 mm in rods
Take the eiffel tower, roughly 3.3e+05 mm. The conversion is a single multiplication — 3.3e+05 × 0.000198839 — giving 65.6168 rd. Because the relationship is proportional, doubling the input doubles the answer to 131.234 rd.
An Olympic pool: 5e+04 mm in rods
Take an olympic pool, roughly 5e+04 mm. The conversion is a single multiplication — 5e+04 × 0.000198839 — giving 9.94194 rd. Because the relationship is proportional, doubling the input doubles the answer to 19.8839 rd.
How to read your score
Frequently asked questions
How many rods are in one millimeter?
Exactly 0.000198838781516. 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 millimeters to rods?
rods = millimeters × 0.000198838781516. Reversed, millimeters = rods ÷ 0.000198838781516, which is the same as multiplying by 5029.2.
Which is the bigger unit, the millimeter or the rod?
The rod. One millimeter is only 0.000198839 of a rod, so it takes 5029.2 millimeters 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 millimeter?
One thousandth of a metre — the finest gradation on a standard ruler.
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 mm to rd in my head?
Plenty of people do this in their head: divide by 5000 instead of using the exact factor 0.0001988387815. At 100 that shortcut gives 0.02 rods, off by 0.0001161 rods or about 0.58%. Fine for a rough estimate, not fine for anything you are cutting to size or dosing.
Millimeters to rods reference tables
| Millimeters | Rods |
|---|---|
| 0.5 mm | 9.94194e-05 rd |
| 1 mm | 0.000198839 rd |
| 2 mm | 0.000397678 rd |
| 3 mm | 0.000596516 rd |
| 5 mm | 0.000994194 rd |
| 10 mm | 0.00198839 rd |
| 20 mm | 0.00397678 rd |
| 25 mm | 0.00497097 rd |
| 50 mm | 0.00994194 rd |
| 75 mm | 0.0149129 rd |
| 100 mm | 0.0198839 rd |
| 250 mm | 0.0497097 rd |
| 500 mm | 0.0994194 rd |
| 1000 mm | 0.198839 rd |
| 5000 mm | 0.994194 rd |
Exact factor: 1 millimeter = 0.000198838781516 rods.
| Quantity | mm | rd |
|---|---|---|
| A credit card’s long edge | 85.6 mm | 0.01702 rd |
| A door height | 2032 mm | 0.404 rd |
| An Olympic pool | 5e+04 mm | 9.942 rd |
| The Eiffel Tower | 3.3e+05 mm | 65.62 rd |
| A marathon | 4.22e+07 mm | 8390 rd |
| Earth’s diameter | 1.274e+10 mm | 2.534e+06 rd |
Published reference values, converted with the same factor this page uses.