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Linear Mass Density Converter

Convert mass per unit length between kg/m, g/m and lb/ft.

Result

lb/ft
0.033599
g/mlb/ft
10.0007
50.0034
100.0067
250.0168
500.0336
1000.0672

About the Linear Mass Density Converter

The Linear Mass Density Converter converts a mass-per-length value between kilograms per meter, grams per meter, and pounds per foot, the units used to spec cable weight, yarn thickness, rope, and rail weight. It is built for anyone comparing a product spec sheet in one unit system against a project requirement written in another.

How It Works

Enter a value along with its starting unit and the unit you want it displayed in; the calculator converts through a shared kg/m base scale, where 1 kg/m is the reference, 1 g/m equals 0.001 kg/m, and 1 lb/ft equals 1.48816 kg/m. The converted figure appears to six decimal places, and a reference table scales the same conversion across six preset input values.

Result = input value x (base factor of source unit) / (base factor of target unit), where 1 kg/m = 1, 1 g/m = 0.001 kg/m, and 1 lb/ft = 1.48816 kg/m.

Examples

Yarn weight from grams to pounds per foot

The default 50 g/m input (0.05 kg/m) converts to about 0.0336 lb/ft (50 x 0.001 / 1.48816), useful for matching a European yarn label to a pattern written with US weight specs.

Cable weight from kilograms to pounds per foot

A 0.2 kg/m electrical cable converts to roughly 0.1344 lb/ft (0.2 / 1.48816), the kind of figure needed when estimating shipping weight for a cable run measured in feet.

Advantages

  • Converts directly between metric and imperial density units without a manual factor lookup.
  • Includes grams per meter as a finer-grained unit for lightweight materials like wire and yarn.
  • Provides a scaled comparison table so the ratio is visible across several magnitudes in one view.

Common Mistakes

  • Confusing linear mass density (mass per unit length) with area density (mass per unit area), which uses entirely different units.
  • Applying the lb/ft factor to a per-inch or per-yard spec without first converting the length unit.
  • Rounding the g/m value before conversion, which compounds error when the result itself is a small lb/ft figure.

Edge Cases to Watch For

  • lb/ft relies on a rounded conversion factor (1.48816), so results carried to many decimal places may drift slightly from a higher-precision hand calculation.
  • The converter treats the input as a pure mass-per-length figure; it does not account for material density or cross-sectional area, which matter if you're trying to work out a diameter or volume.
  • Very light values in g/m, such as fine yarn or thread, convert to very small lb/ft numbers, so the decimal output needs to be read carefully rather than rounded by eye.

Common Use Cases

  • Textile and knitting suppliers matching yarn or thread weight specs across regions.
  • Electricians and installers comparing cable weight ratings from metric and imperial datasheets.
  • Engineers estimating rope, wire, or rail weight per length for load or shipping calculations.
Written & fact-checked by the Calculateus TeamLast updated August 5, 2026How we verify our formulas

Frequently asked questions

Where is linear mass density used?

Linear mass density rates things measured by length rather than by piece - electrical cable weight per meter, yarn or rope weight, and railway track weight per foot are all commonly specified this way.

Conclusion

This tool handles the metric-to-imperial density conversion so specs from different sources can be compared on equal footing. For structural or load-bearing decisions, always verify against the manufacturer's stated tolerance on the density figure.