Start an RFQ ↗
WhatsAppFast product support

TERMINAL BLOCK WIRE SIZE TOOL

Convert AWG to mm²—without confusing size with fit.

Calculate nominal conductor geometry, see which current catalog ranges include the selected AWG and carry the exact wire construction into a checkable terminal block RFQ.

Open the calculator →Build a replacement request
WIRE GAUGE18American Wire Gauge
NOMINAL METAL AREA0.823Square millimeters

GEOMETRIC REFERENCE · NOT AMPACITY OR TERMINAL APPROVAL

ONE NUMBER DOES NOT DESCRIBE THE CONNECTION

Convert the conductor, then verify the termination.

AWG and mm² describe conductor size using different systems. A nominal area helps communication, but terminal acceptance also depends on solid, stranded or ferruled construction, the clamping point, preparation and the exact model standard.

01 / GAUGELower AWG number means a larger nominal conductor.
02 / AREACalculated mm² is metallic area, not outside insulation diameter.
03 / TERMINATIONSolid, stranded and ferruled ranges may differ on one product.
04 / RATINGWire size alone does not establish terminal current or voltage.

AWG TO MM² REFERENCE

Convert a wire gauge, then check documented terminal ranges.

Choose an AWG size to calculate its nominal solid-wire diameter and cross-sectional area. Matching models are based only on the AWG ranges published in the current YIHENTRA source data.

SELECTED GAUGE18 AWGA lower AWG number identifies a larger nominal conductor
NOMINAL SOLID DIAMETER1.02 mmBare round conductor geometry, before insulation
NOMINAL METAL AREA0.823 mm²Calculated reference—not a terminal acceptance rating
CURRENT CATALOG SHORTLIST

40 documented model references include 18 AWG.

Inclusion means the supplied AWG range contains the selected gauge. Confirm solid, stranded or ferruled conductor acceptance, strip length, torque, rating, drawing and sample for the exact model.

The mm² result is the nominal metallic area calculated from the AWG diameter progression. It does not convert insulation diameter, stranded bundle diameter, ferrule size, ampacity or a product approval. Product wire ranges can legitimately pair an AWG range with a different stated metric maximum; use the exact product data.

FROM CABLE MARKING TO RFQ

Six checks before calling a terminal “suitable.”

  1. 01

    Identify the conductor construction.

    Record solid or stranded conductor, strand class, insulation, ferrule style and whether one or two conductors enter each clamping point.

  2. 02

    Use the actual AWG marking.

    Enter the gauge printed on the wire or confirmed by the cable drawing. Do not estimate it from the outside insulation diameter.

  3. 03

    Treat mm² as a geometric reference.

    The calculator derives nominal bare-conductor area. It does not turn a stranded or ferruled conductor into an automatically accepted terminal size.

  4. 04

    Open the documented model range.

    Use the matching model list as a shortlist, then check pitch, positions, mounting, connection method and exact conductor data.

  5. 05

    Confirm preparation and tightening.

    Check strip length, ferrule acceptance, insertion method, screw torque or actuator instructions for the exact terminal block.

  6. 06

    Close ratings, documents and sample.

    Current and voltage are application- and product-specific. Confirm the drawing, required approval evidence and a wired sample before release.

AWG 8–28 REFERENCE TABLE

Nominal diameter, metallic area and current catalog coverage.

Values are calculated from the AWG diameter progression and rounded for selection reference. The model count only checks whether a supplied AWG range contains that gauge; it is not a compatibility claim.

AWGDIAMETERNOMINAL AREADOCUMENTED MODELS
8 AWG3.26 mm8.37 mm²2 range matches ↓
9 AWG2.91 mm6.63 mm²2 range matches ↓
10 AWG2.59 mm5.26 mm²6 range matches ↓
11 AWG2.3 mm4.17 mm²6 range matches ↓
12 AWG2.05 mm3.31 mm²20 range matches ↓
13 AWG1.83 mm2.62 mm²20 range matches ↓
14 AWG1.63 mm2.08 mm²27 range matches ↓
15 AWG1.45 mm1.65 mm²27 range matches ↓
16 AWG1.29 mm1.31 mm²38 range matches ↓
17 AWG1.15 mm1.04 mm²38 range matches ↓
18 AWG1.02 mm0.823 mm²40 range matches ↓
19 AWG0.912 mm0.653 mm²36 range matches ↓
20 AWG0.812 mm0.518 mm²36 range matches ↓
21 AWG0.723 mm0.41 mm²33 range matches ↓
22 AWG0.644 mm0.326 mm²33 range matches ↓
23 AWG0.573 mm0.258 mm²22 range matches ↓
24 AWG0.511 mm0.205 mm²22 range matches ↓
25 AWG0.455 mm0.162 mm²19 range matches ↓
26 AWG0.405 mm0.129 mm²19 range matches ↓
27 AWG0.361 mm0.102 mm²19 range matches ↓
28 AWG0.321 mm0.081 mm²19 range matches ↓

CURRENT CATALOG WIRE-RANGE DIRECTORY

12 documented ranges across 40 model pages.

These strings reproduce the current supplied product data. They are not normalized into a new rating: open the exact model and confirm conductor construction, terminal preparation, ratings, drawing and sample.

DOCUMENTED CATALOG RANGE

28-18AWG (0.75mm²)

2 current models; verify conductor type and exact product data.

DOCUMENTED CATALOG RANGE

28-16AWG (1.5mm²)

10 current models; verify conductor type and exact product data.

DOCUMENTED CATALOG RANGE

28-12AWG (2.5mm²)

7 current models; verify conductor type and exact product data.

DOCUMENTED CATALOG RANGE

24-16AWG (1.5mm²)

1 current model; verify conductor type and exact product data.

DOCUMENTED CATALOG RANGE

24-10AWG (6.0mm²)

2 current models; verify conductor type and exact product data.

DOCUMENTED CATALOG RANGE

22-14AWG (2.5mm²)

7 current models; verify conductor type and exact product data.

DOCUMENTED CATALOG RANGE

22-12AWG (2.5mm²)

2 current models; verify conductor type and exact product data.

DOCUMENTED CATALOG RANGE

22-12AWG (4.0mm²)

2 current models; verify conductor type and exact product data.

DOCUMENTED CATALOG RANGE

20-12AWG (4.0mm²)

3 current models; verify conductor type and exact product data.

DOCUMENTED CATALOG RANGE

18-10AWG (4.0mm²)

1 current model; verify conductor type and exact product data.

DOCUMENTED CATALOG RANGE

18-10AWG (6.0mm²)

1 current model; verify conductor type and exact product data.

DOCUMENTED CATALOG RANGE

18-8AWG (10.0mm²)

2 current models; verify conductor type and exact product data.

SOURCE AND INTERPRETATION BOUNDARY

Use the conversion for communication—not as an approval shortcut.

The NIST copper-wire table provides American Wire Gauge diameter and cross-section references. Current manufacturer literature also separates conductor construction and ferrule conditions instead of treating one AWG/mm² pair as a universal terminal fit.

NIST · COPPER WIRE TABLESAmerican Wire Gauge diameter and cross-section referenceGovernment technical handbook ↗PHOENIX CONTACT · PCB TERMINALSSeparate solid, stranded and ferruled connection capacitiesManufacturer catalog ↗WAGO · PCB CONNECTIONProduct-specific AWG and mm² conductor rangesManufacturer technical page ↗

BUYER FAQ

AWG, mm² and terminal block selection questions.

What does AWG mean?

American Wire Gauge is a logarithmic size system for round conductors. Within the range shown here, a lower gauge number means a larger nominal conductor diameter and metallic area.

Is 12 AWG exactly 2.5 mm²?

No. The nominal geometric area calculated for 12 AWG is about 3.31 mm². A terminal data sheet may pair an AWG acceptance range with a different metric maximum because conductor construction, test standard and connection condition must be stated separately.

Can the conversion prove that a wire fits a terminal block?

No. The exact terminal must accept the conductor type, cross-section, ferrule condition and number of conductors. Strip length, clamping method, drawing and sample also need checking.

Can insulation diameter be converted from AWG?

No. AWG describes the conductor size, while finished cable diameter also depends on insulation material, wall thickness, stranding and cable construction.

Does wire size determine current rating?

No. This tool does not calculate ampacity. Terminal rating, conductor temperature, installation, applicable standard and system design must all be confirmed.

Why are only 40 YIHENTRA models in the shortlist?

Those 40 model pages contain a supplied wire-range field. Two additional pages are pin headers without direct conductor termination, and eleven Spring references remain pending supplier confirmation rather than receiving inferred wire data.

SEND THE CONDUCTOR—NOT JUST A CONVERSION

Request a model check with the real wire construction.

Include the cable marking or drawing, solid/stranded/ferruled condition, pitch, positions, mounting, current, voltage, quantity, market and required documents.

Open the wire-size RFQ →Download RFQ ExcelBrowse technical drawings →Check strip length and recommended torque →Compare termination methods →