Copper Wire Weight Calculator - Round, Square, Hex, and Rectangle Wire

A copper wire weight calculator turns two simple measurements, the cross-section and the run length, into the mass of the copper or copper-alloy conductor. Pick the shape, pick the alloy, enter the diameter or side length, and the result returns pounds, kilograms, per-foot, and per-meter values.

• • AWG Copper Weight Lookup: Electricians verify the per-foot weight of 4/0, 2/0, 12 AWG, or any other AWG conductor against the published chart without weighing the spool.
• • Scrap and Recycling Estimates: Scrap yards estimate the recoverable copper in a coil or a bundle of offcuts before setting a pickup price.
• • Shipping and Freight Planning: Coil and reel shippers add up the mass across an order so the freight class and carrier weight limits match the load.
• • Coursework and Lab Calculations: Physics and materials-science students work the textbook density times area times length problem.

Copper wire is one of the most familiar conductor shapes in physics and electrical engineering courses. The calculation, density multiplied by cross-sectional area multiplied by length, is the same density-times-volume formula used for any solid object.

When the wire is sized for an electrical circuit, Ohm's law calculator covers the voltage, current, and resistance side of the same problem so the result and the ampacity can be checked against each other.

The formula multiplies three things: the density of the copper or copper alloy, the cross-sectional area, and the length. The cross-section geometry changes the area formula, but the rest of the math is identical for all four wire shapes.

• density: Mass per unit volume of the copper or copper alloy. Pure copper is 8.935 g/cm^3 (about 0.32373 lb/in^3). Alloys shift this value because alloying elements have different densities.
• cross_sectional_area: Area of the wire profile perpendicular to its length. Round uses pi r^2, square uses side squared, rectangle uses width times height, and hexagon uses (sqrt(3)/2) times the across-flats width squared.
• length: Run length of the wire, converted internally to inches so the same formula works regardless of the input unit.

The unit selectors handle the conversions. Density entered in g/cm^3 is multiplied by 0.036127 to get lb/in^3, which matches the NIST SI conversion factor. Length in feet, meters, or millimeters is multiplied by the inch-equivalent (12, 39.3701, or 0.0393701) so the volume ends up in cubic inches.

According to Copper Development Association, Electrical Busbar, the standard copper used for building wire and rectangular busbar is Copper No. 110 (C11000) at 99 percent IACS, which matches the pure copper preset here and produces 0.646 lb per foot for 4/0 AWG and 0.020 lb per foot for 12 AWG when the 8.94 g/cm^3 density is applied.

When the result feeds a mechanical lifting or thermal expansion estimate, work energy power calculator covers the force, work, and power side of the same density-times-area-times-length relationship used in this formula.

Four concepts explain why density, cross-section, and length each contribute to the result and how the same formula covers all four copper wire weight shapes.

Two wires of the same diameter but different alloy can differ in weight by 5 to 10 percent. A 4/0 yellow brass rod is noticeably lighter than a 4/0 pure copper rod, and that difference is what the alloy selector captures. Use it whenever the spec sheet lists a UNS designation.

When the alloy density is given in g/cm^3 and the wire count needs to be checked in moles, mole and molar mass calculator converts the result into moles and molar mass so the same input can be used in stoichiometry problems.

Six steps take you from a wire spec or measured piece of copper to a clean result that matches AWG charts and metric datasheets.

1. 1 Pick the Wire Shape: Use round for AWG building wire, square and rectangle for bus bar or transformer wire, and hex for brass or bronze stock.
2. 2 Pick the Alloy Preset: Select pure copper unless the spec sheet names a UNS alloy. Custom opens the density field for less common alloys.
3. 3 Enter the Cross-Section Dimension: Type the diameter (round), side (square), width (rectangle), or across-flats width (hex). For rectangle, also enter the height.
4. 4 Enter the Length: Type the run length and pick the unit (mm, cm, m, in, ft, yd). The calculator converts the length to inches internally.
5. 5 Read the Total Weight: The Total Weight card shows pounds and kilograms for the whole piece. Use this when the order is for one spool.
6. 6 Cross-Check the per-Foot and per-Meter Outputs: Use the Weight per Foot and Weight per Meter rows to verify the result against the published AWG chart.

Suppose you have a 4/0 pure copper building-wire spool and need to know how much a 250 ft run weighs. Pick round wire, pick pure copper, type 0.46 for the diameter, type 250 for the length, and pick feet. The result is 161.4 lb (73.2 kg), matching the AWG chart.

When the estimate needs to be paired with the heat-treatment temperature for the alloy, annealing temperature calculator covers the time and temperature side of the same copper and copper-alloy materials problem.

A focused calculator for this material saves lookup time, prevents unit mistakes, and gives the same number in the units every reference chart uses.

• • Matches the AWG Chart: Returns the standard per-foot and per-meter weight that AWG copper tables and metric datasheets quote, so the result can be checked against the chart.
• • Avoids Unit Confusion: Picks up length in mm, cm, m, in, ft, or yd and density in g/cm^3 or lb/in^3, so the same entry works whether the spec sheet is metric or imperial.
• • Covers the Common Alloys: Includes pure copper plus cartridge brass, yellow brass, commercial bronze, beryllium copper, copper-nickel, and aluminum bronze.
• • Works for Round, Square, Hex, and Rectangle: Accepts round wire, square wire, rectangular bus bar, and hexagonal stock so the same calculator handles AWG building wire, transformer winding wire, and brass rod stock.
• • Returns Both Weight and Volume: Shows total volume in cubic inches alongside the weight so the result can be cross-checked against a separate volume-to-mass calculator.

The biggest practical benefit is the alloy selector. Switching from pure copper to cartridge brass drops a 4/0 round wire result from 0.646 lb/ft to 0.615 lb/ft, a 5 percent shift large enough to change a freight quote.

When the calculated value is used to size the support force for a hanging span or tension member, forces and Newton's laws calculator covers the mass-to-force conversion that turns the result into a usable mechanical load.

Five factors shift the result up or down from the textbook value, plus two limitations to keep in mind when comparing to a real spool.

• • The calculator assumes a solid uniform cross-section. Litz wire and stranded conductors have a copper fill factor below 100 percent, so the value overestimates the copper content.
• • The result is the theoretical weight at room temperature. Very long cable runs at elevated temperatures will show a slightly lower weight per foot.

For stranded wire, multiply the calculated weight by the typical copper fill factor (about 0.85 to 0.95 for standard Class B stranding). Always check the spec sheet when the wire is plated or stranded, since the bare copper value is the lower bound.

According to NIST SI Units, 1 g/cm^3 equals 0.036127 lb/in^3 because 1 g equals 0.00220462 lb and 1 in^3 equals 16.387064 cm^3, which gives the conversion factor used to convert alloy density into the lb/in^3 used by this calculator.

When the wire is used as a tension member or a bus bar and the bending stress matters, beam bending stress calculator covers the stress and deflection side of the same density, area, and length relationship used in this calculator.