mm² to AWG Conversion Chart
Complete reference for converting between metric cross-section (mm²) and American Wire Gauge (AWG), with ampacity and resistance for copper conductors. Used for RV, marine, and off-grid DC wiring.
All values assume copper at 20°C ambient. Looking for the reverse direction? See AWG to mm².
mm² to AWG Reference Table
Standard pairings used in international cable sizing. Click any row with a detail page for voltage drop tables, fuse sizing, and applications.
| mm² | AWG | Ampacity | Resistance (mΩ/m) | Typical Use | Details |
|---|---|---|---|---|---|
| 0.75 mm² | 18 AWG | 7 A | 23.20 | Signal wires, low-power LEDs | View → |
| 1 mm² | 16 AWG | 10 A | 17.80 | Interior lights, small fans | — |
| 1.5 mm² | 14 AWG | 15 A | 11.90 | Standard lighting circuits | View → |
| 2.5 mm² | 13 AWG | 20 A | 7.14 | 12V branch circuits, USB outlets | — |
| 4 mm² | 12 AWG | 25 A | 4.46 | Water pumps, USB chargers | View → |
| 6 mm² | 10 AWG | 35 A | 2.98 | Fridges, MPPT to battery | View → |
| 10 mm² | 8 AWG | 50 A | 1.78 | Sub-panels, DC-DC chargers | — |
| 16 mm² | 6 AWG | 65 A | 1.12 | Inverter feeds, shore-power chargers | — |
| 25 mm² | 4 AWG | 85 A | 0.71 | Battery interconnects, mid inverters | View → |
| 35 mm² | 2 AWG | 110 A | 0.51 | Heavy battery cables | — |
| 50 mm² | 1 AWG | 135 A | 0.36 | Large inverters, main battery leads | — |
| 70 mm² | 1/0 | 170 A | 0.26 | High-power inverters | — |
| 95 mm² | 2/0 | 200 A | 0.19 | 1/0 — high-power inverters | — |
| 120 mm² | 3/0 | 235 A | 0.15 | 2/0 — high-power bus bars | — |
| 150 mm² | 4/0 | 285 A | 0.12 | 3/0 — bow thrusters, windlasses | — |
| 185 mm² | 5/0 | 330 A | 0.10 | 4/0 — high-power marine | — |
| 240 mm² | 6/0 | 400 A | 0.07 | 300 MCM — industrial DC | — |
Ampacity values are for copper conductors in chassis wiring at 20°C ambient. Free-air ratings are higher; engine-bay or bundled-cable installations are lower (derate 10–20%).
Detailed Conversion Pages
Each page below has voltage drop tables for 12V and 24V, fuse sizing, applications, and FAQs specific to that cable size.
18 AWG (0.75 mm²) is the thinnest standard cable still considered "wiring" in DC systems — below it, you are into signal-wire and pre-tinned BMS-cable territory. It handles small loads under 7 A: indicator LEDs, low-power dome lights, sensor feeds, and the trigger sides of relays. In stocked metric markets, 0.75 mm² is the smallest cable typically sold off the spool, available alongside 1.0 mm² and 1.5 mm². Anything below 0.75 mm² is usually multi-conductor sheathed cable for trailer plugs or sensor harnesses.
12 AWG (4 mm²) is the workhorse of 15–25 A DC circuits. It is the gauge most camper builders pick for the water pump, vent fan, and USB charger branches — heavier than the 14 AWG lighting circuit, lighter than the 10 AWG fridge feed. In 12V automotive applications it is the standard for accessory sockets, electric awnings, dual-purpose Maxxair fans, and small inverter feeds up to roughly 300 W. The metric pair is 4 mm², stocked in every auto-electrical shop in Europe.
10 AWG is the workhorse of medium-current DC wiring. It handles the loads that are too heavy for general lighting (14 AWG / 12 AWG) but lighter than direct battery interconnects (8 AWG and above). In a typical camper or boat, 10 AWG runs from the fuse panel to the compressor fridge, the heater fan, and from the MPPT solar charge controller to the battery on systems up to roughly 30 amps.
14 AWG is the gauge most camper electricians default to for branch circuits in the 5–15 A range. It handles interior LED lighting, USB outlets, small fans, and 12V cigarette sockets without breaking a sweat. Below 14 AWG you are into signal-wire territory (16 / 18 AWG); above it (12 AWG) is for water pumps, vent fans, and small motor loads. In standard metric cable, 14 AWG corresponds to 1.5 mm² — the most stocked size in European auto-electrical and marine shops.
4 AWG is where DC wiring stops being light branch circuits and starts being serious power transmission. It is the default for battery bank interconnects, feeds to medium inverters (1000–1500 W class at 12V), and the main distribution between battery and fuse panel. At this gauge, friction-fit terminals stop being acceptable — every 4 AWG termination needs a hexagonal crimp die, heat-shrink, and ideally a torque-checked stud connection.
mm² to AWG Calculator
For any custom load and cable length, use the wire gauge calculator. It returns the recommended mm² and AWG size, voltage drop, power loss, and fuse rating.
= 60W
= 16.4 ft (one way, round-trip calculated automatically)
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Result
Fuse Size
Materials
- Battery cable2.5 mm² · 2 × 6 m
- Fuse7.5 A · Blade (ATC/ATO) · × 1
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Download Cable for iOSFrequently Asked Questions
How do I convert mm² to AWG?
mm² values map to standard AWG pairings used in international cable sizing: 0.75 mm² = 18 AWG, 1.0 mm² = 16 AWG, 1.5 mm² = 14 AWG, 2.5 mm² = 13/12 AWG, 4 mm² = 12 AWG, 6 mm² = 10 AWG, 10 mm² = 8 AWG, 16 mm² = 6 AWG, 25 mm² = 4 AWG, 35 mm² = 2 AWG, 50 mm² = 1 AWG. The exact AWG of a metric cable falls between two AWG steps; the standard pairing is the closest AWG match.
Is 6 mm² the same as 10 AWG?
6 mm² is the standard metric pairing for 10 AWG. The precise AWG cross-section of 10 AWG is 5.26 mm², slightly less than 6 mm². In datasheets, electrical codes, and cable spec tables, 6 mm² and 10 AWG are matched and used interchangeably. The 6 mm² cable carries slightly more current than the strict AWG specification.
How many amps can each mm² size carry?
Standard ampacity values for copper at 20°C in chassis wiring: 0.75 mm² = 7 A, 1.0 mm² = 10 A, 1.5 mm² = 15 A, 2.5 mm² = 20 A, 4 mm² = 25 A, 6 mm² = 35 A, 10 mm² = 50 A, 16 mm² = 65 A, 25 mm² = 85 A, 35 mm² = 110 A, 50 mm² = 135 A. For free-air installation or high-temperature environments, derate by 10–20%.
What is the AWG equivalent of 2.5 mm²?
2.5 mm² is between 13 AWG (2.62 mm²) and 14 AWG (2.08 mm²). In international standards it is most commonly paired with 13 AWG, which carries 20 A in chassis wiring. In US AWG-only tables, 14 AWG is the common substitution for 2.5 mm² cable; check the ampacity column for the actual current rating.
Why are mm² and AWG sizes not exactly equivalent?
AWG is a logarithmic scale with discrete steps (each step changes cross-section by ~26%). Standard metric cable sizes (1.5, 2.5, 4, 6, 10, 16, 25, 35, 50 mm²) are independent values, not chosen to match AWG. So most metric sizes fall between two AWG steps. International cable standards define a closest-match pairing for each — that is the convention used in this chart.
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Reverse: AWG to mm²
Same chart, indexed by AWG — 18 AWG through 4/0 AWG.