AWG gauge: diameter, section and metric equivalent
d(inches) = 0.005 × 92^((36 − n) / 39)
American Wire Gauge both ways: from the gauge to diameter and cross-section, or from a metric diameter to the closest gauge with the gap shown. The series is geometric and exact, each gauge dividing the diameter by 92^(1/39), and the tool computes from that definition rather than copying a table. The closest European metric landmark is given, with the warning that goes with it: AWG 14 is 2.08 mm², not 2.5. Ampacity is not served, and the note says why: it depends on insulation, temperature, bundling and the electrical code, four things a formula does not carry.
1.6277 mm
- Calculation
- d = 0.005″ × 92^((36 − 14) / 39) = 0.064084″
- Cross-section
- 2.0809 mm²
AWG 14 is 1.6277 mm in diameter, a cross-section of 2.0809 mm².
The AWG series is geometric and exact: each gauge divides the diameter by 92^(1/39) ≈ 1.123, anchored on AWG 36 = 0.005 inch and 0000 = 0.46 inch. The number goes UP as the wire gets thinner, a legacy of the number of drawing passes.
The metric section shown is only a landmark: normalised European sections (1.5, 2.5, 4 mm²…) coincide with no AWG. AWG 14 is 2.08 mm², not 2.5: for a replacement, take the equal or next larger metric section.
This tool gives no current rating: ampacity depends on the insulation and its temperature class, the ambient temperature, conductor bundling and the applicable electrical code, four things a formula does not carry. For an installation, the only reference is the standard in force (NEC, IEC…) or the cable datasheet.
Scientific dossier
What the tool computes, what it assumes, where it stops being valid, and where its data comes from.
Method & formulasd(inches) = 0.005 × 92^((36 − n) / 39)
d(inches) = 0.005 × 92^((36 − n) / 39)
section = π d² / 4
anchors: AWG 36 = 0.005″, AWG 0000 = 0.46″
The series is not an arbitrary table: it is an exact geometric progression between two anchors, defined that way by ASTM B258. Each gauge divides the diameter by 92^(1/39) ≈ 1.123; six gauges double the section, three gauges multiply it by about 1.6.
- AWG
- · American Wire Gauge: the number goes UP as the wire gets thinner, a legacy of the number of drawing passes.
- 00, 000, 0000
- · the large gauges beyond 0, entered as −1, −2, −3.
- Cross-section
- · the conductor area, πd²/4, the quantity that governs the wire’s resistance.
- Ampacity
- · the allowable current of an installed cable: a property of the installation, not of the copper alone.
Validity domainThe formula covers solid conductors from 0000 to 40 AWG.
The formula covers solid conductors from 0000 to 40 AWG. Stranded cables carry the same number for an equivalent section, but their outer diameter is larger than the solid one. No current rating is given: ampacity depends on the insulation and its temperature class, the surroundings, conductor bundling and the applicable code, and the only reference is the standard in force or the cable datasheet.
Reading the resultThe metric landmark shown is only a landmark: normalised European sections coincide with no AWG, and to replace an AWG wire with metric you take the equal or next larger section, never the nearest rounding downwards.
The metric landmark shown is only a landmark: normalised European sections coincide with no AWG, and to replace an AWG wire with metric you take the equal or next larger section, never the nearest rounding downwards. In diameter → gauge mode, the displayed gap says whether your wire really is an AWG or a neighbouring metric.