40 AWG
- Bare solid diameter
- 0.08 mm
- Geometric area
- 0.005 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 40
- AWG designation
- 40
VALICALC · TECHNICAL REFERENCE
AWG Wire Size Chart
Look up AWG diameter and area, compare nearby metric conductor sizes and send a selected gauge to the voltage-drop calculator with clear limits.
ValiCalc · AWG Wire Size Chart
https://www.valicalc.com/awg-wire-size-chart
Dataset v1.2.0 · verified 2026-10-06
Print the selected answer, conditions, scope and source summary.
Display: metric.
QUICK LOOKUP
Search within the verified subset. Numeric sizes match complete designations; a nearby size is a candidate, not an exact match.
SELECTED REFERENCE
4 AWG
- Bare solid diameter
- 5.189 mm
- Geometric area
- 21.151 mm²
- Next listed metric area
- 25 mm²
All fields & cell provenance
- Gauge index
- 4
- AWG designation
- 4
- Gauge: Copper wire tables — Generated AWG equation; metric candidates reuse the existing calculator series · verified 2026-10-06 · source value 4 AWG.
- Bare solid diameter: Copper wire tables — Generated AWG equation; metric candidates reuse the existing calculator series · verified 2026-10-06.
- Geometric area: Copper wire tables — Generated AWG equation; metric candidates reuse the existing calculator series · verified 2026-10-06.
- Next listed metric area: Copper wire tables — Generated AWG equation; metric candidates reuse the existing calculator series · verified 2026-10-06 · source value 25.
- Gauge index: Copper wire tables — Generated AWG equation; metric candidates reuse the existing calculator series · verified 2026-10-06 · source value 4.
- AWG designation: Copper wire tables — Generated AWG equation; metric candidates reuse the existing calculator series · verified 2026-10-06 · source value 4.
v1.2.0 · verified 2026-10-06
Use this value
Review the selected values and units in the calculator before applying them.
Use gauge in Voltage Drop →Use reviewed values in cable resistance →4 AWG5.189 mmBack to answer ↑
Explore the verified data
44 matching rows · 44 in this subset
| Gauge | Bare solid diameter | Geometric area | Next listed metric area | Actions |
|---|---|---|---|---|
| 40 AWG | 0.08 mm | 0.005 mm² | 0.5 mm² | |
| 39 AWG | 0.09 mm | 0.006 mm² | 0.5 mm² | |
| 38 AWG | 0.101 mm | 0.008 mm² | 0.5 mm² | |
| 37 AWG | 0.113 mm | 0.01 mm² | 0.5 mm² | |
| 36 AWG | 0.127 mm | 0.013 mm² | 0.5 mm² | |
| 35 AWG | 0.143 mm | 0.016 mm² | 0.5 mm² | |
| 34 AWG | 0.16 mm | 0.02 mm² | 0.5 mm² | |
| 33 AWG | 0.18 mm | 0.025 mm² | 0.5 mm² | |
| 32 AWG | 0.202 mm | 0.032 mm² | 0.5 mm² | |
| 31 AWG | 0.227 mm | 0.04 mm² | 0.5 mm² | |
| 30 AWG | 0.255 mm | 0.051 mm² | 0.5 mm² | |
| 29 AWG | 0.286 mm | 0.064 mm² | 0.5 mm² | |
| 28 AWG | 0.321 mm | 0.081 mm² | 0.5 mm² | |
| 27 AWG | 0.361 mm | 0.102 mm² | 0.5 mm² | |
| 26 AWG | 0.405 mm | 0.129 mm² | 0.5 mm² | |
| 25 AWG | 0.455 mm | 0.162 mm² | 0.5 mm² | |
| 24 AWG | 0.511 mm | 0.205 mm² | 0.5 mm² | |
| 23 AWG | 0.573 mm | 0.258 mm² | 0.5 mm² | |
| 22 AWG | 0.644 mm | 0.326 mm² | 0.5 mm² | |
| 21 AWG | 0.723 mm | 0.41 mm² | 0.5 mm² |
39 AWG
- Bare solid diameter
- 0.09 mm
- Geometric area
- 0.006 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 39
- AWG designation
- 39
38 AWG
- Bare solid diameter
- 0.101 mm
- Geometric area
- 0.008 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 38
- AWG designation
- 38
37 AWG
- Bare solid diameter
- 0.113 mm
- Geometric area
- 0.01 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 37
- AWG designation
- 37
36 AWG
- Bare solid diameter
- 0.127 mm
- Geometric area
- 0.013 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 36
- AWG designation
- 36
35 AWG
- Bare solid diameter
- 0.143 mm
- Geometric area
- 0.016 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 35
- AWG designation
- 35
34 AWG
- Bare solid diameter
- 0.16 mm
- Geometric area
- 0.02 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 34
- AWG designation
- 34
33 AWG
- Bare solid diameter
- 0.18 mm
- Geometric area
- 0.025 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 33
- AWG designation
- 33
32 AWG
- Bare solid diameter
- 0.202 mm
- Geometric area
- 0.032 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 32
- AWG designation
- 32
31 AWG
- Bare solid diameter
- 0.227 mm
- Geometric area
- 0.04 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 31
- AWG designation
- 31
30 AWG
- Bare solid diameter
- 0.255 mm
- Geometric area
- 0.051 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 30
- AWG designation
- 30
29 AWG
- Bare solid diameter
- 0.286 mm
- Geometric area
- 0.064 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 29
- AWG designation
- 29
28 AWG
- Bare solid diameter
- 0.321 mm
- Geometric area
- 0.081 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 28
- AWG designation
- 28
27 AWG
- Bare solid diameter
- 0.361 mm
- Geometric area
- 0.102 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 27
- AWG designation
- 27
26 AWG
- Bare solid diameter
- 0.405 mm
- Geometric area
- 0.129 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 26
- AWG designation
- 26
25 AWG
- Bare solid diameter
- 0.455 mm
- Geometric area
- 0.162 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 25
- AWG designation
- 25
24 AWG
- Bare solid diameter
- 0.511 mm
- Geometric area
- 0.205 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 24
- AWG designation
- 24
23 AWG
- Bare solid diameter
- 0.573 mm
- Geometric area
- 0.258 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 23
- AWG designation
- 23
22 AWG
- Bare solid diameter
- 0.644 mm
- Geometric area
- 0.326 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 22
- AWG designation
- 22
21 AWG
- Bare solid diameter
- 0.723 mm
- Geometric area
- 0.41 mm²
- Next listed metric area
- 0.5 mm²
More dimensions
- Gauge index
- 21
- AWG designation
- 21
KEEP THE JOB MOVING
Where does this result go next?
How to use this data
d = 0.127 × 92^((36−gauge)/39) mm; A = πd²/4. Gauge indices −3, −2, −1 and 0 mean 4/0, 3/0, 2/0 and 1/0. The next listed metric area is a comparison candidate, not an exact interchangeable size.
CHECK THE METHOD
Worked example
4 AWG gives about 5.189 mm bare-solid diameter and 21.15 mm² geometric area. The next listed metric candidate is 25 mm².
REAL INPUTS · CLEAR METHOD
Practical worked examples
Illustrative scenarios using this page’s calculation or verified reference model. Change the assumptions for your own job.
12 AWG bare conductor geometry
Given
- Selected row
- 12 AWG
Calculation / lookup method
d = 0.127 × 92^((36−gauge)/39) mm; A = πd²/4. Gauge indices −3, −2, −1 and 0 mean 4/0, 3/0, 2/0 and 1/0. The next listed metric area is a comparison candidate, not an exact interchangeable size.
Result
- Bare solid diameter
- 2.053 mm
- Geometric area
- 3.309 mm²
- Next listed metric area
- 4 mm²
Bare solid diameter and geometric area do not describe jacket diameter or allowable current. A next-listed metric area is a geometry comparison, not an interchangeable cable rating.
Open this reference scenario ↑10 AWG geometric area
Given
- Selected row
- 10 AWG
Calculation / lookup method
d = 0.127 × 92^((36−gauge)/39) mm; A = πd²/4. Gauge indices −3, −2, −1 and 0 mean 4/0, 3/0, 2/0 and 1/0. The next listed metric area is a comparison candidate, not an exact interchangeable size.
Result
- Bare solid diameter
- 2.588 mm
- Geometric area
- 5.261 mm²
- Next listed metric area
- 6 mm²
Use the geometric area in a resistance/voltage-drop model, then review conductor material, insulation and installation separately.
Open this reference scenario ↑4 AWG versus listed metric geometry
Given
- Selected row
- 4 AWG
Calculation / lookup method
d = 0.127 × 92^((36−gauge)/39) mm; A = πd²/4. Gauge indices −3, −2, −1 and 0 mean 4/0, 3/0, 2/0 and 1/0. The next listed metric area is a comparison candidate, not an exact interchangeable size.
Result
- Bare solid diameter
- 5.189 mm
- Geometric area
- 21.151 mm²
- Next listed metric area
- 25 mm²
The selected row is an AWG geometry scenario. No ampacity conclusion follows from its area alone.
Open this reference scenario ↑Continue the reference workflow
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:
44 authored AWG examples, 4/0 through 40. Metric candidates are the existing calculator series, not guaranteed equivalent products.
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 tables ↗
Type A · US Bureau of Standards · Circular 31, 2nd edition, 1914
Original generated scenarios from the stated equations; source tables/text/drawings are not reproduced.
Full provenance & artifact record
- Source checked
- 2026-10-06
- Use basis
- authored-formula
- Artifact SHA-256
- No retained source artifact hash; see the stated source and verification record.