WireGaugeCalc Free calculator · NEC cited · works offline
Bare Ground Conductor Conduit Fill
Bare ground conductor conduit fill is simple with WireGaugeCalc, since you add the bare equipment ground to the other conductors and the calculator returns the total fill.
It uses the NEC Chapter 9 bare conductor area for the ground, so the fill math reflects its smaller cross-section.
You get a fill percentage that includes the ground and stays under the 40% limit.
Open the calculatorFill against NEC Chapter 9, Table 1 (40% for 3+ conductors) with Table 4 and Table 5 areas. Field aid only, verify against the current NEC and your local authority having jurisdiction.
How The Bare Equipment Ground Affects Conduit Fill
The bare equipment grounding conductor is a conductor in the raceway, so it counts toward fill.
It uses the bare conductor area from NEC Chapter 9, so it takes less room than an insulated wire of the same size.
WireGaugeCalc adds the bare ground to the phase and neutral areas, then compares the total to the 40% limit.
What Goes Into A Fill Check With A Bare Ground In EMT
Fill with a bare ground conductor depends on:
- Conduit type, such as EMT, PVC, or RMC
- Conduit trade size and its internal area
- Phase and neutral conductor areas
- Bare ground area from NEC Chapter 9
- Total conductor count for the 40% limit
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
Does the bare equipment ground count in conduit fill?
Yes, the bare equipment grounding conductor counts toward fill like any other conductor, using its bare area from NEC Chapter 9. Confirm the result against the current NEC and your local authority having jurisdiction.
Is a bare ground smaller in fill than an insulated ground?
Yes, a bare ground has no insulation, so its cross-sectional area is smaller and it adds less to the total fill than an insulated ground of the same size.
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.