Span to Bolt Conversion Calculator: Free Online Tool

Convert spans to bolts with our free online length converter.

Span to Bolt Calculator

Span
Bolt

How to Use the Calculator:

  1. Enter the value you want to convert in the 'From' field (Span).
  2. The converted value in Bolt will appear automatically in the 'To' field.
  3. Use the dropdown menus to select different units within the Length category.
  4. Click the swap button (⇌) to reverse the conversion direction.

How to Convert Span to Bolt

Converting Span to Bolt involves multiplying the value by a specific conversion factor, as shown in the formula below.

Formula:

1 Span = 0.0075 bolts

Example Calculation:

Convert 10 spans: 10 × 0.0075 = 0.075 bolts

Disclaimer: For Reference Only

These conversion results are provided for informational purposes only. While we strive for accuracy, we make no guarantees regarding the precision of these results, especially for conversions involving extremely large or small numbers which may be subject to the inherent limitations of standard computer floating-point arithmetic.

Not for professional use. Results should be verified before use in any critical application. View our Terms of Service for more information.

What is a Span and a Bolt?

The Span is an ancient unit of length based on the distance across an outstretched human hand, measured from the tip of the thumb to the tip of the little finger (or sometimes the index finger). As an anthropomorphic unit, its length was inherently variable, depending on the size of an individual's hand.

Historically, it was often defined in relation to other body-based units:

  • Typically considered half a cubit.
  • Often equated to 3 palms (where a palm is the width of the hand across the base of the fingers).
  • Sometimes defined as 12 digits (fingerbreadths).

A common, though unofficial, modern estimate for a span is around 9 inches or approximately 22.86 centimeters (cm).

A Bolt is a commercial unit of length primarily used for measuring rolls of cloth or fabric. Unlike standardized units like the meter or yard, the length of a bolt is not fixed and can vary significantly depending on the type of material, the manufacturer, the country of origin, and trade customs.

Common lengths often associated with a bolt include:

  • 40 yards (approximately 36.58 meters) - Frequently cited, especially for cottons and silks in the US.
  • 100 yards (approximately 91.44 meters) - Often used for heavier fabrics like canvas.
  • Other lengths such as 30, 50, 60, or 120 yards may also be encountered.

The bolt represents a quantity convenient for wholesale trade, manufacturing, and inventory management rather than a precise scientific measurement.

Note: The Span is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Bolt belongs to the imperial/US customary system.

History of the Span and Bolt

The span is one of the oldest informal units of measurement, used by numerous ancient civilizations, including the Egyptians, Israelites, Greeks, and Romans, due to the convenience of using the human hand.

  • Ancient Egypt & Mesopotamia: The span was used alongside the cubit and digit. The relationship (often 1 span = 1/2 cubit) was fundamental in their systems.
  • Biblical References: The span is mentioned in the Bible (e.g., Exodus 28:16 describing the High Priest's breastplate, Goliath's height in some interpretations).
  • Ancient Greece & Rome: Used as a practical subdivision of the cubit.
  • Medieval Europe: Continued in informal use and sometimes appeared in texts defining lengths. In England, it was often standardized (unofficially) as 9 inches.

Like other anthropomorphic units, the span fell out of official use with the development and adoption of more standardized systems like the Imperial (inches, feet) and Metric (meters) systems, which provided necessary precision for trade, science, and industry.

The concept of the bolt emerged from the practical needs of the textile industry. As cloth production scaled up, manufacturers and merchants needed a standardized way to handle, store, and trade large quantities of fabric. Winding cloth onto a roll or board (the "bolt") provided a convenient package.

The length associated with a bolt likely developed through trade customs specific to different types of fabric and regions. There was never a universal legal standard defining its length, leading to the wide variations seen historically and currently. While retail sales shifted towards measurement by the yard or meter, the bolt remained a useful unit in wholesale and industrial contexts. Even with the global adoption of the metric system, the term "bolt" persists in the textile trade as a reference to a full roll of fabric, though the exact length is usually specified separately in yards or meters.

Common Uses for spans and bolts

Explore the typical applications for both Span (imperial/US) and Bolt (imperial/US) to understand their common contexts.

Common Uses for spans

The span is now obsolete for precise or official measurements but is still encountered or used in specific contexts:

  • Informal Estimation: Used for quick, rough measurements of moderate lengths where precision is not critical (e.g., gardening, crafts, estimating object sizes).
  • Historical Texts: Found in ancient and medieval documents, requiring understanding for interpretation.
  • Anthropology & Archaeology: Relevant when studying historical measurement systems or interpreting dimensions from ancient sites.
  • Figurative Language: Can be used metaphorically to denote a small distance or extent ("life span").
  • Understanding Historical Units: Key to grasping the relationship between units like the digit, palm, and cubit in ancient systems.

Common Uses for bolts

The bolt is almost exclusively used within the textile industry:

  • Wholesale Trade: Fabric manufacturers sell cloth to distributors or large buyers in bolts.
  • Manufacturing: Clothing and upholstery manufacturers purchase fabric by the bolt for production runs.
  • Inventory Management: Textile mills, warehouses, and large retailers manage stock using bolts as units.
  • Industrial Fabrics: Suppliers of canvas, vinyl, and other industrial textiles often sell material by the bolt.

It is generally not used for retail sales to consumers, where fabric is typically measured and cut to specific lengths (yards or meters) from the bolt.

Frequently Asked Questions

Questions About Span (span)

How long is a span?

There is no single, universally fixed length for a span because it's based on human hand size. However:

  • A common historical and modern estimate is 9 inches (in).
  • This is approximately 22.86 centimeters (cm) or 0.2286 meters (m).
  • Historically, it was often defined as half a cubit, which varied (e.g., a common cubit of ~18 inches would yield a 9-inch span).

What is the relationship between a span and a cubit?

In many historical systems, a span was considered half (1/2) of a cubit. Since cubits themselves varied (e.g., common cubit vs. royal cubit), the exact length of the span derived this way also varied.

What is the relationship between a span and a palm or digit?

Common relationships, though varying by system, were:

  • 1 span ≈ 3 palms (where a palm is the width of the hand).
  • 1 span ≈ 12 digits (where a digit is the width of a finger).

Is the span an SI unit?

No, the span is not an SI unit. It is an ancient, non-standardized, anthropomorphic unit. The SI base unit for length is the meter (m).

Is the span still used today?

The span is not used for any official, scientific, or commercial measurements. Its use is limited to informal estimations, historical context, and figurative language. People might still use their own hand span for a quick size check.

Where does the name 'span' come from?

The word "span" comes from Old English spann, related to the verb spannan, meaning "to stretch, extend, or connect". This directly reflects the action of stretching the hand to measure the unit.

About Bolt (bolt)

How long is a bolt of cloth?

There is no single standard length. It depends heavily on the fabric type and manufacturer. Common lengths include:

  • 40 yards (~36.58 m)
  • 100 yards (~91.44 m)
  • Other lengths like 30, 50, 60, or 120 yards are also possible. Always check the specific product information for the actual length of a particular bolt.

How many yards are in a bolt?

Commonly 40 yards or 100 yards, but this is highly variable.

How many meters are in a bolt?

Based on common yard lengths:

  • A 40-yard bolt is approximately 36.58 meters.
  • A 100-yard bolt is approximately 91.44 meters.

Is the bolt a standardized unit?

No, it is not a standardized unit of length like the yard or meter. It's a commercial trade unit whose length varies.

Is the bolt still used today?

Yes, the term "bolt" is still widely used in the wholesale textile industry and manufacturing contexts to refer to a full roll of fabric, although the precise length is usually specified in yards or meters.

Is this related to the fastener "bolt"?

No, the bolt unit for cloth is completely unrelated to the metal fastener known as a bolt. They share the same name but have entirely different meanings and origins.

Conversion Table: Span to Bolt

Span (span)Bolt (bolt)
10.008
50.038
100.075
250.188
500.375
1000.75
5003.75
1,0007.5

All Length Conversions

Meter to KilometerMeter to HectometerMeter to DecimeterMeter to CentimeterMeter to MillimeterMeter to InchMeter to FootMeter to YardMeter to MileMeter to Nautical MileMeter to MicrometerMeter to NanometerMeter to Light YearMeter to Astronomical UnitMeter to ParsecMeter to AngstromMeter to Point (Typography)Meter to Mil/ThouMeter to FathomMeter to FurlongMeter to Link (Gunter's)Meter to PaceMeter to SpanMeter to DigitMeter to Cable LengthMeter to EllMeter to FingerMeter to Roman MileMeter to StadionMeter to Chi (Chinese)Meter to Shaku (Japanese)Meter to Li (Chinese)Meter to ToiseMeter to BoltMeter to RopeMeter to SmootMeter to SajeneMeter to KenMeter to WaMeter to VaraMeter to AlnMeter to Cubit (Royal/Egyptian)Meter to VerstaMeter to ArpentMeter to Ri (Japanese)Meter to KlafterMeter to YojanaMeter to SkeinKilometer to MeterKilometer to HectometerKilometer to DecimeterKilometer to CentimeterKilometer to MillimeterKilometer to InchKilometer to FootKilometer to YardKilometer to MileKilometer to Nautical MileKilometer to MicrometerKilometer to NanometerKilometer to Light YearKilometer to Astronomical UnitKilometer to ParsecKilometer to AngstromKilometer to Point (Typography)Kilometer to Mil/ThouKilometer to FathomKilometer to FurlongKilometer to Link (Gunter's)Kilometer to PaceKilometer to SpanKilometer to DigitKilometer to Cable LengthKilometer to EllKilometer to FingerKilometer to Roman MileKilometer to StadionKilometer to Chi (Chinese)Kilometer to Shaku (Japanese)Kilometer to Li (Chinese)Kilometer to ToiseKilometer to BoltKilometer to RopeKilometer to SmootKilometer to SajeneKilometer to KenKilometer to WaKilometer to VaraKilometer to AlnKilometer to Cubit (Royal/Egyptian)Kilometer to VerstaKilometer to ArpentKilometer to Ri (Japanese)Kilometer to KlafterKilometer to YojanaKilometer to SkeinHectometer to MeterHectometer to KilometerHectometer to DecimeterHectometer to CentimeterHectometer to MillimeterHectometer to InchHectometer to FootHectometer to YardHectometer to MileHectometer to Nautical MileHectometer to MicrometerHectometer to NanometerHectometer to Light YearHectometer to Astronomical UnitHectometer to ParsecHectometer to AngstromHectometer to Point (Typography)Hectometer to Mil/ThouHectometer to FathomHectometer to FurlongHectometer to Link (Gunter's)Hectometer to PaceHectometer to SpanHectometer to Digit