A surveyor's chain is 66 feet.
Chains to Femtometers Converter — ch to fm
Convert Chain (ch) to Femtometer (fm) using the exact conversion factor (1 chain = 2.01168e+16 femtometer). See the formula, worked examples, and conversion table.
Chains to Femtometers converter
Converter
Length Converter
Convert SI, imperial, US customary, astronomical, scientific, and historical length units.
Context values
Some unit families need one extra value for a physically accurate result.
Femtometer is 1e-15 meter units.
Result = input x 20.1168 / 1e-15.
Length uses the meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Chains to Femtometers
Chain and Femtometer both measure length. Specifically: A surveyor's chain is 66 feet, and femtometer is 1e-15 meter units.
Formula
femtometers = chains × 2.01168e+16
This factor comes from each unit's defined relationship to the category's base unit: 1 chain equals 20.1168 base units, and 1 femtometer equals 1e-15 base units, so dividing one by the other gives the direct chain-to-femtometer factor of 2.01168e+16.
Simple example
1 ch × 2.01168e+16 = 2.01168e+16 fm
1 chain = 2.01168e+16 femtometers.
Real-world example
10 ch × 2.01168e+16 = 2.01168e+17 fm
10 chains = 2.01168e+17 femtometers.
Conversion table
| Chain (ch) | Femtometer (fm) |
|---|---|
| 1 ch | 2.01168e+16 fm |
| 5 ch | 1.00584e+17 fm |
| 10 ch | 2.01168e+17 fm |
| 21.0975 ch | 4.244142e+17 fm |
| 42.195 ch | 8.488284e+17 fm |
| 100 ch | 2.01168e+18 fm |
Reverse conversion: Femtometer to Chain
2.01168e+16 fm × 4.97097e-17 = 1 ch
2.01168e+16 femtometers = 1 chain.
chains = femtometers × 4.97097e-17
For a page dedicated to this direction, see Femtometer to Chain.
Understanding the Chain (ch)
A surveyor's chain is 66 feet.
Understanding the Femtometer (fm)
Femtometer is 1e-15 meter units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many femtometers are in 1 chain?
1 chain equals 2.01168e+16 femtometers, using the exact defined conversion factor rather than an estimate.
How do I convert chain to femtometer?
Multiply the chain value by 2.01168e+16. The converter above does this instantly to whatever precision you set.
How do I convert femtometer back to chain?
Use the reverse factor: 1 femtometer equals 4.97097e-17 chains. You can also use the swap control in the converter above to flip the direction instantly.
What is a chain?
Chain (ch) is a unit of length.
What is a femtometer?
Femtometer (fm) is a unit of length.
Is the chain to femtometer conversion exact?
Yes. Both chain and femtometer are defined by fixed standards rather than physical artifacts, so the factor of 2.01168e+16 used above is exact to as many digits as you choose to display.