Chain to Millimeter Converter

Length · unit-converter

Convert Chain to Millimeter with a fixed input and output unit, step-by-step formula line, and reference tables. All calculations use SI-based definitions (international yard, nautical mile, etc.).

Calculator

From: Chain (chain)

To: Millimeter (mm)

About Chain

The chain is a surveying unit equal to 66 feet (20.1168 meters) exactly. It appears in land measurement and legacy civil engineering records.

About Millimeter

The millimeter is a metric unit equal to one thousandth of a meter (0.001 m). It is used for precision engineering, 3D printing, and small tolerances.

How to convert chains to millimeters

1 chain is equal to 20116.79999999999927 millimeter:

1 chain = (20.1168 m ÷ 0.001 m) mm = 20116.79999999999927 mm

Each chain is defined as 20.1168 m and each millimeter as 0.001 m, so one chain equals 20.1168 ÷ 0.001 mm = 20116.79999999999927 mm.

Let d(chain) be the numeric value of the same length measured in Chain (chain), and d(mm) the value in Millimeter (mm). Then:

d(mm) = d(chain) × (20.1168 / 0.001)

Equivalently, divide by how many chain fit into one mm (meters per mm divided by meters per chain):

d(mm) = d(chain) ÷ 0.00004970969538

Or: millimeter = chain ÷ 0.00004970969538

Examples

Example #1: Convert 20 chain to millimeter

20 chain = 20 chain × (20.1168/0.001) mm = 402336 mm

20 chain = 20 chain ÷ 0.00004970969538 = 402336 mm

Example #2: Convert 50 chain to millimeter

50 chain = 50 chain × (20.1168/0.001) mm = 1005840 mm

50 chain = 50 chain ÷ 0.00004970969538 = 1005840 mm

Summary

To convert Chain to Millimeter, multiply the value in chain by the ratio of meters per chain divided by meters per mm. Equivalently: value_mm = value_chain × (20.1168 / 0.001). Numerically, 1 chain equals 20116.8 mm.

Relationship context

You are converting between US customary / imperial (Chains) and metric (SI) (Millimeters). Metric units are decimal; imperial units use inches, feet, yards, and miles tied to the international yard definition. Nautical miles are defined in meters (1 nmi = 1,852 m). This tool uses SI-based factors so results stay consistent with modern standards.

Conversion tables

Chain (chain)Millimeter (mm)
0.12,011.68
120,116.8
240,233.6
360,350.4
480,467.2
5100,584
6120,700.8
7140,817.6
8160,934.4
9181,051.2
Chain (chain)Millimeter (mm)
10201,168
20402,336
30603,504
40804,672
501,005,840
601,207,008
701,408,176
801,609,344
901,810,512
1002,011,680