Canadian work
CEC mode and metric conductor sizes.
Canadian drawings name large conductors by area in square millimetres where US drawings say kcmil. This page converts every published conductor size both ways, explains what CEC mode changes in your saved circuit list, and is blunt about the one thing that does not convert.
Read this first
Areas convert. Ampacities do not.
AmpSizer publishes NEC figures only. The CEC allowable-ampacity tables in CSA C22.1 are a different dataset with different values, different correction factors, and different conditions of use, and nothing on this site substitutes for them. Metric conductor areas convert exactly; ampacities do not convert at all. For Canadian work, size from CSA C22.1 and your provincial amendments.
That distinction is the whole reason this page exists. The cross-sectional area of a conductor is a geometric fact, so 250 kcmil is 127 mm² in any country. How much current that conductor is allowed to carry is a code decision, and the CEC makes it from its own tables under its own conditions of use. Treating an NEC ampacity as a CEC ampacity is how a conductor ends up undersized, so AmpSizer states the NEC figure, names the edition beside it, and stops there.
Conversion
AWG and kcmil to mm²
NEC 2023Every conductor area below is transcribed from the 2023 NEC (NFPA 70, 2023). The code is republished on a three-year cycle and adoption varies by jurisdiction - confirm against your locally adopted edition and your authority having jurisdiction (AHJ) before you build.
| Size | Circular mils | Area (mm²) |
|---|---|---|
| 14 AWG | 4,110 | 2.08 |
| 12 AWG | 6,530 | 3.31 |
| 10 AWG | 10,380 | 5.26 |
| 8 AWG | 16,510 | 8.37 |
| 6 AWG | 26,240 | 13.30 |
| 4 AWG | 41,740 | 21.15 |
| 3 AWG | 52,620 | 26.66 |
| 2 AWG | 66,360 | 33.63 |
| 1 AWG | 83,690 | 42.41 |
| 1/0 AWG | 105,600 | 53.51 |
| 2/0 AWG | 133,100 | 67.44 |
| 3/0 AWG | 167,800 | 85.03 |
| 4/0 AWG | 211,600 | 107 |
| 250 kcmil | 250,000 | 127 |
| 300 kcmil | 300,000 | 152 |
| 350 kcmil | 350,000 | 177 |
| 400 kcmil | 400,000 | 203 |
| 500 kcmil | 500,000 | 253 |
| 600 kcmil | 600,000 | 304 |
| 700 kcmil | 700,000 | 355 |
| 750 kcmil | 750,000 | 380 |
| 800 kcmil | 800,000 | 405 |
| 900 kcmil | 900,000 | 456 |
| 1000 kcmil | 1,000,000 | 507 |
| 1250 kcmil | 1,250,000 | 633 |
| 1500 kcmil | 1,500,000 | 760 |
| 1750 kcmil | 1,750,000 | 887 |
| 2000 kcmil | 2,000,000 | 1013 |
Source: NFPA 70, National Electrical Code, Chapter 9, Table 8. Published by NFPA.NEC 2023Transcribed from the 2023 NEC (NFPA 70, 2023). Confirm against your locally adopted edition and your authority having jurisdiction (AHJ).
Nothing in this table is transcribed. A circular mil is defined as the area of a circle one mil (0.001 inch) across, so one circular mil is exactly 0.000506707 mm², and each row is that constant multiplied by the published circular-mil area. The test suite pins the result against the metric designations the trade uses.
Vocabulary
Same thing, different word
| On this site | In Canada | What it means |
|---|---|---|
| NEC (NFPA 70) | CEC Part I (CSA C22.1) | The document adopted by provincial and territorial regulators in Canada. |
| AWG and kcmil | AWG and mm² | Canadian drawings and cable markings commonly name large conductors by metric area. |
| AHJ (authority having jurisdiction) | Provincial or territorial electrical inspection authority | Who accepts the installation, and who publishes the local amendments. |
| Equipment grounding conductor | Bonding conductor | The same conductor in the field, named differently in each document. |
In the app
What CEC mode does
CEC mode relabels conductors in your saved circuit list with their metric cross-sectional area alongside the AWG or kcmil designation, so the list reads the way a Canadian drawing does. It changes labels, not values.
It is free. Save a circuit from any calculator, open your circuit list, and switch the toggle to CEC: every conductor picks up its metric area, and the caveat above rides along with it. Nothing about the mode is behind a paywall, because the most important thing it has to tell a Canadian reader is a warning, and warnings are not for sale.
FAQ
Frequently asked questions
Can I use AmpSizer for Canadian work?
For conductor geometry, voltage drop, and conduit fill arithmetic, the physics is the same and the metric conversions on this page are exact. For allowable ampacity, no. AmpSizer publishes NEC figures only. The CEC allowable-ampacity tables in CSA C22.1 are a different dataset with different values, different correction factors, and different conditions of use, and nothing on this site substitutes for them. Metric conductor areas convert exactly; ampacities do not convert at all. For Canadian work, size from CSA C22.1 and your provincial amendments.
What does CEC mode actually do?
CEC mode relabels conductors in your saved circuit list with their metric cross-sectional area alongside the AWG or kcmil designation, so the list reads the way a Canadian drawing does. It changes labels, not values. It is free, along with the rest of the saved-circuit workspace at the free list size.
What is 250 kcmil in mm2?
250 kcmil is 126.7 mm2, which the trade names as 127 mm2. A circular mil is the area of a circle 0.001 inch across, so the conversion is exact arithmetic rather than a table lookup: multiply circular mils by pi/4 times 0.0254 squared. Every row in the table above is computed that way from the published conductor areas.
Why does 14 AWG show 2.08 mm2 and not 2.5 mm2?
2.08 mm2 is the true cross-sectional area of a 14 AWG conductor. 2.5 mm2 is a separate metric conductor size in its own right, slightly larger, and the two are not interchangeable for sizing. This page reports the actual area of the AWG conductor, not the nearest metric size to it.
Which document should I size Canadian conductors from?
CSA C22.1, the Canadian Electrical Code Part I, as adopted and amended by your province or territory. Every figure AmpSizer publishes comes from the 2023 NEC (NFPA 70, 2023) instead, and the two are not interchangeable.