Convert Span to Chain
Convert spans to chains instantly. 1 span = 0.0113636364 chain — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Chain to Span converter for the reverse conversion.
Units explained
Span
A span is an Imperial unit of length equal to 9 inches (228.6 mm). Historically, it represented the distance from the tip of an extended thumb to the tip of an extended little finger.
The span derives from this natural body-measurement and was standardised at 9 inches in English customary practice.
Spans are rare in modern commerce but appear in historical English literature, biblical translation studies, and reproduction crafts. Some construction and gardening still use 'span' informally.
Ancient body-measure origin; standardised in English customary practice at 9 inches; became exact via the 1959 International Yard and Pound Agreement.
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.
Span to Chain conversion formula
The relationship between spans and chains:
To convert spans to chains, multiply the value in spans by 0.0113636364. To reverse, multiply chains by 88.
How to use this converter
Type a value into the calculator. The result in chains updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Chain to Span converter for the reverse direction.
Step-by-step: convert spans to chains
- Write down the value in spans (span).
- Multiply that value by the factor 0.0113636364.
- The product is the equivalent value in chains (ch).
- To reverse, multiply the chain value by 88.
Worked examples
Example 1 — Convert 1 span to ch:
1 × 0.0113636364 = 0.0113636364 ch
Example 2 — Convert 100 span to ch:
100 × 0.0113636364 = 1.1363636364 ch
Real-world example — Adult height conversion
A 1.8-span-tall person measures a value in chains that converts the height to the unit favoured by American forms, schools, or driver's licences. This is daily routine for anyone living between metric and imperial systems.
1.8 span × 0.0113636364 = 0.0204545455 ch
Real-world example — Fabric purchase length
Two spans of fabric equals a value in chains essential for tailors and textile buyers sourcing material from international suppliers that quote in different units.
2 span × 0.0113636364 = 0.0227272727 ch
Real-world example — Maritime depth conversion
A 10-span sounding depth converts cleanly into chains. Recreational divers and sailors translate between the two units whenever they read legacy charts against modern depth-sounder displays.
10 span × 0.0113636364 = 0.1136363636 ch
Span to Chain conversion table
Standard reference values for converting spans to chains:
| Span [span] | Chain [ch] |
|---|---|
| 0.01 | 0.0001136364 |
| 0.1 | 0.0011363636 |
| 1 | 0.0113636364 |
| 2 | 0.0227272727 |
| 3 | 0.0340909091 |
| 4 | 0.0454545455 |
| 5 | 0.0568181818 |
| 10 | 0.1136363636 |
| 20 | 0.2272727273 |
| 30 | 0.3409090909 |
| 40 | 0.4545454545 |
| 50 | 0.5681818182 |
| 100 | 1.1363636364 |
| 500 | 5.6818181818 |
| 1000 | 11.3636363636 |
Frequently asked questions
How many chains is 1 span?
How do I convert spans to chains?
How do I convert chains back to spans?
How many chains is 100 spans?
Popular length unit conversions
Convert Span to other length units
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Metric / SI (4 units)
Imperial / US Customary (26 units)
Sources & references
Conversion factor (1 span = 0.0113636364 ch) 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 Hydrographic Organization — Resolution on the Nautical Mile
International authority that standardised the nautical mile at exactly 1852 m in 1929 — the value adopted worldwide for sea and air navigation.