WireGaugeCalc Free calculator · NEC cited · works offline
5mm Wire Amp Rating
5mm wire amp rating is simple with WireGaugeCalc, since you enter the conductor and the tool returns the ampacity for the cross-section.
It converts the metric size to a comparable copper gauge and reads the ampacity, so you know the current the wire can carry.
You confirm the limit fast, so the circuit load stays inside the rating.
Open the calculatorAllowable ampacity from NEC Table 310.16 at the chosen termination temperature. Field aid only, verify against the current NEC and your local authority having jurisdiction.
How The 5mm Conductor Amp Rating Is Read
Ampacity follows the cross-sectional area and insulation, since a thicker conductor carries more current before it overheats.
A 5mm diameter copper wire has a large area near 19.6 square millimeters, so it carries a substantial current at the right termination temperature.
What Sets The Current Limit On 5mm Wire
The amp rating depends on these factors:
- Whether 5mm means diameter or area, since the two differ
- Conductor material, copper or aluminum
- Insulation temperature rating
- Comparable AWG, near 6 AWG for a 5mm diameter copper wire
- Ambient temperature and bundling, which derate the conductor
One app for every NEC calculation
WireGaugeCalc keeps the calculations you reach for most in one place:
- Voltage drop and wire sizing for any run
- Conduit fill for EMT, PVC, and RMC
- Box fill and junction box sizing
- Ampacity and temperature derating
- Motor circuit and load calculations
- Conduit bend offsets and saddles
Built for the field, works offline
The whole app runs on your phone, so it keeps working in a basement, an attic, or a job site with no signal.
There is no account to create and nothing to load. Open it, run the number, and get back to work.
- No signup and no signal needed
- Answers in a tap, not a spreadsheet
- Same tool on phone, tablet, and desktop
Every result cites the NEC article
Each answer shows the table or formula it came from, so you can check the method and learn the code as you go.
That makes the app useful on the job and during exam prep, since the reasoning is right next to the number.
Switch the code year your job runs on
Jurisdictions adopt the NEC at different times, so you can match the calculation to the code in force:
- NEC 2017, 2020, and 2023 tables
- Copper and aluminum conductors
- 60, 75, and 90 degree C terminations
- Single-phase and three-phase systems
Run the number, then get back to work
Stop flipping through a paper book or hopping between calculator sites. Enter your values, read the code-cited answer, and move on. Free to use, no signup.
Open the calculatorFrequently asked questions
How many amps can 5mm wire carry?
A 5mm diameter copper conductor is close to 6 AWG, which carries roughly 55 to 65 amps depending on the termination column. Confirm the size meaning and rating against the current NEC and your local authority having jurisdiction.
Is 5mm a diameter or a cross-section?
It can be either, so check the spec, since a 5mm diameter is about 19.6 square millimeters of area while a 5mm squared cable is smaller and carries less current.
Is WireGaugeCalc free to use?
Yes. Every calculator is free to run with no signup. A paid tier adds saved projects, PDF reports, and extra code years, but the core math stays free.
Does it work without internet?
Yes. The app runs on your device, so it keeps working with no signal on a job site, in a basement, or in an attic.
Are the results code accurate?
Results follow published NEC tables and standard formulas, and each answer shows the article it came from. It is a field aid, not a stamp of approval, so verify against the current code and your local authority before you wire anything.
Which NEC code year does it use?
You can switch between NEC 2017, 2020, and 2023, since jurisdictions adopt the code at different times. Pick the year your job runs on.