0.75 mm2 to AWG: 18 AWG, and Why It Actually Fits

0.75 mm² converts to **18 AWG**, and like 0.5 mm² this one needs no argument.

18 AWG is 0.823 mm² — 10% larger than 0.75 mm² — and it clears the resistance limit. Nearest gauge and safe substitute are the same answer.

No judgment call

19 AWG is the arithmetic near-miss, but it is an odd gauge and therefore not stocked, and it misses the limit by 8% anyway. Both reasons point the same way.

The next stocked size up is 16 AWG at 75% larger, which is a long way past what the design asked for. So 18 AWG is not just the best of three options — it is comfortably the only sensible one.

The same pairing seen from the other side

This conversion is worth reading alongside 18 AWG in mm², because the two pages describe the same relationship from opposite ends and reach a slightly different conclusion.

Going metric to AWG, as here, 18 AWG is 10% larger and passes. Straightforward.

Going AWG to metric, 18 AWG converts to 0.823 mm² and sits between 0.75 and 1 mm². It fails the 1 mm² limit by 16% and passes 0.75 mm², which makes 0.75 mm² the defensible match rather than the usual round-up. That is one of the very few places on this site where rounding *down* is the correct advice.

Both statements describe the same fact: 18 AWG and 0.75 mm² belong together, and 1 mm² is a step past what 18 AWG can support.

Conductor diameter

A solid conductor of 0.75 mm² works out to 0.977 mm across.

Solid 18 AWG measures 1.02 mm, which sits just above the class 1 maximum for 0.75 mm² — a reminder that 18 AWG is the larger conductor of the pair.

Class 5 and class 6 share the 1.3 mm maximum and the same resistance limit, differing only in strand fineness. At this size that decides whether the conductor survives a cabinet door loom or eventually breaks a strand. See conductor classes 1, 2, 5 and 6.

Ampacity is barely tabulated

0.75 mm² does not appear in the general current-carrying capacity tables, which start at 1.5 mm². On the American side, 18 AWG appears only in the 90 °C column, at 14 A.

Neither omission is accidental. This is a control and signal size, and where it carries current the rating comes from the equipment standard or the flexible cord rules rather than the power circuit tables.

Where 0.75 mm² is used

Flexible cords for appliances and luminaires, control panel wiring, relay and contactor coils, internal equipment wiring, and low-voltage lighting.

It is one of the most common sizes in flexible cord across the metric world, which is why the conversion comes up often when equipment crosses between markets.

FAQ

What is 0.75 mm² in AWG?

18 AWG. At 0.823 mm² it is 10% larger than 0.75 mm², and it meets the 0.75 mm² conductor resistance limit.

Is 0.75 mm² the same as 18 AWG?

Close, and functionally interchangeable in most cases. 18 AWG is 10% larger and satisfies the requirement, which is not true of most pairings.

Can I use 19 AWG instead?

No, for two reasons. It is 13% smaller and misses the resistance limit by 8%, and odd gauges are not stocked.

What is 0.75 mm² in mm diameter?

A solid conductor is 0.977 mm across. Stranded measures up to 1.2 mm, flexible up to 1.3 mm.

How many amps does 0.75 mm² carry?

It is not listed in the general ampacity tables, which start at 1.5 mm². For flexible cords the rating comes from the cord standard or the equipment standard.

Why is 18 AWG sometimes matched to 1 mm² instead?

Because 18 AWG at 0.823 mm² sits between 0.75 and 1 mm². Going from AWG to metric, the usual advice is to round up to 1 mm². But 18 AWG fails the 1 mm² resistance limit and passes 0.75 mm², so 0.75 mm² is the better match on the number that gets tested.

Reference

Work the other direction from 18 AWG, or use the converter.