Convert Millimeter to Barleycorn
Convert millimeters to barleycorns instantly. 1 millimeter = 0.1181102358 barleycorn — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Barleycorn to Millimeter converter for the reverse conversion.
Units explained
Millimeter
A millimeter is a metric unit of length equal to one thousandth of a meter (1/1000 m). It is the standard small-scale unit in the SI system and is widely used wherever sub-centimeter precision matters.
The millimeter was defined alongside the meter when France adopted the metric system in 1795, using the standard SI prefix milli- (from Latin mille, "thousand") to denote one-thousandth.
Millimeters are used in engineering drawings, machining, manufacturing, paper sizes, rainfall measurement, and any context where dimensions below one centimeter need to be specified clearly. Most rulers worldwide are marked in millimeters.
Adopted in 1795 in France as part of the original metric system; standardized internationally by the Metre Convention in 1875 and confirmed in the SI in 1960.
Barleycorn
A barleycorn is an Imperial unit of length equal to one third of an inch (about 8.47 mm). It is the basis of UK shoe sizing and is one of the oldest English length units still in use.
The barleycorn derives from the average length of a grain of barley as a natural reference. Standardised at exactly 1/3 inch by the Statute of Edward II in 1324, which used three barleycorns to define an inch.
Barleycorns are the foundation of UK and US children's shoe sizing — each whole size differs by one barleycorn. Also occasionally referenced in horse-handling and historical English literature.
Standardised in 1324 by the Statute of Edward II at 1/3 inch; the value became exact in 1959 when the inch was fixed at 25.4 mm.
Millimeter to Barleycorn conversion formula
The relationship between millimeters and barleycorns:
To convert millimeters to barleycorns, multiply the value in millimeters by 0.1181102358. To reverse, multiply barleycorns by 8.4666667.
How to use this converter
Type a value into the calculator. The result in barleycorns updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Barleycorn to Millimeter converter for the reverse direction.
Step-by-step: convert millimeters to barleycorns
- Write down the value in millimeters (mm).
- Multiply that value by the factor 0.1181102358.
- The product is the equivalent value in barleycorns (barleycorn).
- To reverse, multiply the barleycorn value by 8.4666667.
Worked examples
Example 1 — Convert 1 mm to barleycorn:
1 × 0.1181102358 = 0.1181102358 barleycorn
Example 2 — Convert 100 mm to barleycorn:
100 × 0.1181102358 = 11.8110235755 barleycorn
Real-world example — Ruler-scale measurements
A 30-millimeter school ruler converts cleanly to barleycorns — useful when buying a desk accessory from a retailer whose product specs use a different unit.
30 mm × 0.1181102358 = 3.5433070727 barleycorn
Real-world example — Hardware-scale dimensions
A 10-millimeter fastener or component is about as long as a thumbnail. Mechanics and DIY enthusiasts convert between millimeters and barleycorns daily when mixing metric and imperial tools.
10 mm × 0.1181102358 = 1.1811023576 barleycorn
Real-world example — Postcard and small-object dimensions
A postcard is about 5 millimeters wide. Converting to barleycorns is essential for international postal addressing forms that ask for dimensions in different units across countries.
5 mm × 0.1181102358 = 0.5905511788 barleycorn
Millimeter to Barleycorn conversion table
Standard reference values for converting millimeters to barleycorns:
| Millimeter [mm] | Barleycorn [barleycorn] |
|---|---|
| 0.01 | 0.0011811024 |
| 0.1 | 0.0118110236 |
| 1 | 0.1181102358 |
| 2 | 0.2362204715 |
| 3 | 0.3543307073 |
| 4 | 0.472440943 |
| 5 | 0.5905511788 |
| 10 | 1.1811023576 |
| 20 | 2.3622047151 |
| 30 | 3.5433070727 |
| 40 | 4.7244094302 |
| 50 | 5.9055117878 |
| 100 | 11.8110235755 |
| 500 | 59.0551178777 |
| 1000 | 118.1102357555 |
Frequently asked questions
How many barleycorns is 1 millimeter?
How do I convert millimeters to barleycorns?
How do I convert barleycorns back to millimeters?
How many barleycorns is 100 millimeters?
Popular length unit conversions
Convert Millimeter to other length units
Show all Millimeter conversions
Metric / SI (17 units)
Imperial / US Customary (27 units)
Nautical (1 units)
Astronomical (9 units)
Atomic / Physics (6 units)
Typographic (3 units)
Sources & references
Conversion factor (1 mm = 0.1181102358 barleycorn) 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.