VALICALC · TECHNICAL REFERENCE

Wire Resistance Chart

Compare copper and aluminum bulk wire resistance by area, length and conductor temperature. Transfer the selected conditions to Voltage Drop.

SCENARIO MATRIX

Search within the verified subset. Numeric sizes match complete designations; a nearby size is a candidate, not an exact match.

SELECTED REFERENCE

Copper 4 mm²

One conductor resistance
0.431025 Ω
Two-conductor loop
0.86205 Ω
Area
4 mm²
All fields & cell provenance
Material
Copper
ρ at 20°C
0.017241 Ω·mm²/m
Temperature coefficient
0.00393 1/°C
ρ at selected temperature
0.017241 Ω·mm²/m

v1.2.0 · verified 2026-10-06 · values use the valid conditions shown above

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Copper 4 mm²0.431025 ΩBack to answer ↑

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22 matching rows · 22 in this subset

Wire Resistance Chart, metric display
Material / areaOne conductor resistanceTwo-conductor loopAreaActions
Aluminum 1.5 mm²1.884267 Ω3.768533 Ω1.5 mm²
Copper 1.5 mm²1.1494 Ω2.2988 Ω1.5 mm²
Aluminum 2.5 mm²1.13056 Ω2.26112 Ω2.5 mm²
Copper 2.5 mm²0.68964 Ω1.37928 Ω2.5 mm²
Aluminum 4 mm²0.7066 Ω1.4132 Ω4 mm²
Copper 4 mm²0.431025 Ω0.86205 Ω4 mm²
Aluminum 6 mm²0.471067 Ω0.942133 Ω6 mm²
Copper 6 mm²0.28735 Ω0.5747 Ω6 mm²
Aluminum 10 mm²0.28264 Ω0.56528 Ω10 mm²
Copper 10 mm²0.17241 Ω0.34482 Ω10 mm²
Aluminum 16 mm²0.17665 Ω0.3533 Ω16 mm²
Copper 16 mm²0.107756 Ω0.215513 Ω16 mm²
Aluminum 25 mm²0.113056 Ω0.226112 Ω25 mm²
Copper 25 mm²0.068964 Ω0.137928 Ω25 mm²
Aluminum 35 mm²0.080754 Ω0.161509 Ω35 mm²
Copper 35 mm²0.04926 Ω0.09852 Ω35 mm²
Aluminum 50 mm²0.056528 Ω0.113056 Ω50 mm²
Copper 50 mm²0.034482 Ω0.068964 Ω50 mm²
Aluminum 70 mm²0.040377 Ω0.080754 Ω70 mm²
Copper 70 mm²0.02463 Ω0.04926 Ω70 mm²

Aluminum 1.5 mm²

One conductor resistance
1.884267 Ω
Two-conductor loop
3.768533 Ω
Area
1.5 mm²
More dimensions
Material
Aluminum
ρ at 20°C
0.028264 Ω·mm²/m
Temperature coefficient
0.00403 1/°C
ρ at selected temperature
0.028264 Ω·mm²/m

Copper 1.5 mm²

One conductor resistance
1.1494 Ω
Two-conductor loop
2.2988 Ω
Area
1.5 mm²
More dimensions
Material
Copper
ρ at 20°C
0.017241 Ω·mm²/m
Temperature coefficient
0.00393 1/°C
ρ at selected temperature
0.017241 Ω·mm²/m

Aluminum 2.5 mm²

One conductor resistance
1.13056 Ω
Two-conductor loop
2.26112 Ω
Area
2.5 mm²
More dimensions
Material
Aluminum
ρ at 20°C
0.028264 Ω·mm²/m
Temperature coefficient
0.00403 1/°C
ρ at selected temperature
0.028264 Ω·mm²/m

Copper 2.5 mm²

One conductor resistance
0.68964 Ω
Two-conductor loop
1.37928 Ω
Area
2.5 mm²
More dimensions
Material
Copper
ρ at 20°C
0.017241 Ω·mm²/m
Temperature coefficient
0.00393 1/°C
ρ at selected temperature
0.017241 Ω·mm²/m

Aluminum 4 mm²

One conductor resistance
0.7066 Ω
Two-conductor loop
1.4132 Ω
Area
4 mm²
More dimensions
Material
Aluminum
ρ at 20°C
0.028264 Ω·mm²/m
Temperature coefficient
0.00403 1/°C
ρ at selected temperature
0.028264 Ω·mm²/m

Copper 4 mm²

One conductor resistance
0.431025 Ω
Two-conductor loop
0.86205 Ω
Area
4 mm²
More dimensions
Material
Copper
ρ at 20°C
0.017241 Ω·mm²/m
Temperature coefficient
0.00393 1/°C
ρ at selected temperature
0.017241 Ω·mm²/m

Aluminum 6 mm²

One conductor resistance
0.471067 Ω
Two-conductor loop
0.942133 Ω
Area
6 mm²
More dimensions
Material
Aluminum
ρ at 20°C
0.028264 Ω·mm²/m
Temperature coefficient
0.00403 1/°C
ρ at selected temperature
0.028264 Ω·mm²/m

Copper 6 mm²

One conductor resistance
0.28735 Ω
Two-conductor loop
0.5747 Ω
Area
6 mm²
More dimensions
Material
Copper
ρ at 20°C
0.017241 Ω·mm²/m
Temperature coefficient
0.00393 1/°C
ρ at selected temperature
0.017241 Ω·mm²/m

Aluminum 10 mm²

One conductor resistance
0.28264 Ω
Two-conductor loop
0.56528 Ω
Area
10 mm²
More dimensions
Material
Aluminum
ρ at 20°C
0.028264 Ω·mm²/m
Temperature coefficient
0.00403 1/°C
ρ at selected temperature
0.028264 Ω·mm²/m

Copper 10 mm²

One conductor resistance
0.17241 Ω
Two-conductor loop
0.34482 Ω
Area
10 mm²
More dimensions
Material
Copper
ρ at 20°C
0.017241 Ω·mm²/m
Temperature coefficient
0.00393 1/°C
ρ at selected temperature
0.017241 Ω·mm²/m

Aluminum 16 mm²

One conductor resistance
0.17665 Ω
Two-conductor loop
0.3533 Ω
Area
16 mm²
More dimensions
Material
Aluminum
ρ at 20°C
0.028264 Ω·mm²/m
Temperature coefficient
0.00403 1/°C
ρ at selected temperature
0.028264 Ω·mm²/m

Copper 16 mm²

One conductor resistance
0.107756 Ω
Two-conductor loop
0.215513 Ω
Area
16 mm²
More dimensions
Material
Copper
ρ at 20°C
0.017241 Ω·mm²/m
Temperature coefficient
0.00393 1/°C
ρ at selected temperature
0.017241 Ω·mm²/m

Aluminum 25 mm²

One conductor resistance
0.113056 Ω
Two-conductor loop
0.226112 Ω
Area
25 mm²
More dimensions
Material
Aluminum
ρ at 20°C
0.028264 Ω·mm²/m
Temperature coefficient
0.00403 1/°C
ρ at selected temperature
0.028264 Ω·mm²/m

Copper 25 mm²

One conductor resistance
0.068964 Ω
Two-conductor loop
0.137928 Ω
Area
25 mm²
More dimensions
Material
Copper
ρ at 20°C
0.017241 Ω·mm²/m
Temperature coefficient
0.00393 1/°C
ρ at selected temperature
0.017241 Ω·mm²/m

Aluminum 35 mm²

One conductor resistance
0.080754 Ω
Two-conductor loop
0.161509 Ω
Area
35 mm²
More dimensions
Material
Aluminum
ρ at 20°C
0.028264 Ω·mm²/m
Temperature coefficient
0.00403 1/°C
ρ at selected temperature
0.028264 Ω·mm²/m

Copper 35 mm²

One conductor resistance
0.04926 Ω
Two-conductor loop
0.09852 Ω
Area
35 mm²
More dimensions
Material
Copper
ρ at 20°C
0.017241 Ω·mm²/m
Temperature coefficient
0.00393 1/°C
ρ at selected temperature
0.017241 Ω·mm²/m

Aluminum 50 mm²

One conductor resistance
0.056528 Ω
Two-conductor loop
0.113056 Ω
Area
50 mm²
More dimensions
Material
Aluminum
ρ at 20°C
0.028264 Ω·mm²/m
Temperature coefficient
0.00403 1/°C
ρ at selected temperature
0.028264 Ω·mm²/m

Copper 50 mm²

One conductor resistance
0.034482 Ω
Two-conductor loop
0.068964 Ω
Area
50 mm²
More dimensions
Material
Copper
ρ at 20°C
0.017241 Ω·mm²/m
Temperature coefficient
0.00393 1/°C
ρ at selected temperature
0.017241 Ω·mm²/m

Aluminum 70 mm²

One conductor resistance
0.040377 Ω
Two-conductor loop
0.080754 Ω
Area
70 mm²
More dimensions
Material
Aluminum
ρ at 20°C
0.028264 Ω·mm²/m
Temperature coefficient
0.00403 1/°C
ρ at selected temperature
0.028264 Ω·mm²/m

Copper 70 mm²

One conductor resistance
0.02463 Ω
Two-conductor loop
0.04926 Ω
Area
70 mm²
More dimensions
Material
Copper
ρ at 20°C
0.017241 Ω·mm²/m
Temperature coefficient
0.00393 1/°C
ρ at selected temperature
0.017241 Ω·mm²/m

How to use this data

ρ(T)=ρ20[1+α(T−20)]; Rone=ρ(T)L/A; Rloop=2Rone. Length is one-way, in metres. This is resistance lookup, not a current-carrying-capacity chart.

    CHECK THE METHOD

    Worked example

    Copper 4 mm², 100 m and 20°C gives 0.431025 Ω per conductor and 0.86205 Ω for a two-wire loop.

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    ReferenceAWG Wire Size ChartReferenceMetric Cable Size Chart

    Common lookup questions

    Can I use these values as a universal specification?

    Geometry and bulk resistance do not establish ampacity, installation method, insulation rating, derating or electrical-code compliance. Diameter is the equivalent bare solid conductor, not finished cable OD.

    TRACEABLE DATA

    Sources, scope & verification

    Dataset v1.2.0
    Last verified:

    22 generated bulk-conductor scenarios. Copper uses annealed IACS values; aluminum uses the existing EC-aluminum model. Product stranding/alloy/AC effects are not included.

    Values are curated product facts or generated scenarios. Paid standards, complete catalogs and source diagrams are not reproduced. A verification date applies to this documented subset.

    Copper wire bulk resistance method ↗

    Type B · US Bureau of Standards · Circular 31, 2nd edition, 1914

    Selected government-authored engineering facts; source conditions are retained.

    Full provenance & artifact record
    Source checked
    2026-10-06
    Use basis
    public-domain
    Artifact SHA-256
    No retained source artifact hash; see the stated source and verification record.

    Aluminum wire tables ↗

    Type B · US Bureau of Standards · Handbook 109, 1972

    Selected government-authored engineering facts; source conditions are retained.

    Full provenance & artifact record
    Source checked
    2026-10-06
    Use basis
    public-domain
    Artifact SHA-256
    No retained source artifact hash; see the stated source and verification record.