Convert Chain to Rope
Convert chains to ropes instantly. 1 chain = 3.3 rope — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Rope to Chain converter for the reverse conversion.
Units explained
Chain
A chain is an Imperial unit of length equal to 66 feet (20.1168 m), or exactly 4 rods or 100 links. It is the central unit in the Gunter chain-based land-survey system.
Defined by Edmund Gunter in 1620 specifically to make land-area arithmetic easy: 10 square chains = 1 acre exactly. The 66-foot length and 100-link subdivision were chosen so chain measurements could be added decimally.
Chains are the fundamental unit of legacy US public land surveys (the entire US township-and-range system uses chains). Modern survey work generally uses meters or feet, but legacy deeds remain in chains.
Invented by Edmund Gunter in 1620; standardised throughout English and American land survey; became exact via the 1959 International Yard and Pound Agreement.
Rope
A rope is an Imperial unit of length equal to 20 feet (6.096 m). It was historically used in English customary measurement, particularly in masonry and some land contexts.
The rope derives from English customary practice and represents 20 feet. Less commonly used than the rod-perch-pole family.
Ropes appear in historical English construction and surveying records but are rare in modern practice. Some legacy specifications and contracts may still reference the unit.
Medieval English customary origin; standardised at 20 feet; became exact via the 1959 International Yard and Pound Agreement.
Chain to Rope conversion formula
The relationship between chains and ropes:
To convert chains to ropes, multiply the value in chains by 3.3. To reverse, multiply ropes by 0.303030303.
How to use this converter
Type a value into the calculator. The result in ropes updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Rope to Chain converter for the reverse direction.
Step-by-step: convert chains to ropes
- Write down the value in chains (ch).
- Multiply that value by the factor 3.3.
- The product is the equivalent value in ropes (rope).
- To reverse, multiply the rope value by 0.303030303.
Worked examples
Example 1 — Convert 1 ch to rope:
1 × 3.3 = 3.3 rope
Example 2 — Convert 100 ch to rope:
100 × 3.3 = 330 rope
Chain to Rope conversion table
Standard reference values for converting chains to ropes:
| Chain [ch] | Rope [rope] |
|---|---|
| 0.01 | 0.033 |
| 0.1 | 0.33 |
| 1 | 3.3 |
| 2 | 6.6 |
| 3 | 9.9 |
| 4 | 13.2 |
| 5 | 16.5 |
| 10 | 33 |
| 20 | 66 |
| 30 | 99 |
| 40 | 132 |
| 50 | 165 |
| 100 | 330 |
| 500 | 1650 |
| 1000 | 3300 |
Frequently asked questions
How many ropes is 1 chain?
How do I convert chains to ropes?
How do I convert ropes back to chains?
How many ropes is 100 chains?
Popular length unit conversions
Convert Chain to other length units
Show all Chain conversions
Metric / SI (4 units)
Imperial / US Customary (26 units)
Sources & references
Conversion factor (1 ch = 3.3 rope) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Astronomical Union — System of Astronomical Constants
The IAU defines astronomical units including the AU (149597870700 m exactly) light-year and parsec used in astronomy and astrophysics.