# Electric Ref: Wire Size & Fill — Ampacity, conduit fill, boxes

> Ampacity, conduit fill, boxes (iPhone/iPad app by Gun woo Kim.)

- Source: https://appshunter.io/ios/app/electric-ref-wire-size-and-fill/id6791592027 (this page in markdown: same URL + `.md`)
- Developer: [Gun woo Kim](https://appshunter.io/developer/1700263119)
- Category: Productivity, Utilities
- Price: Free with in-app purchases
- Age rating: 4+
- Requires: iOS 13.0 · 30 MB
- Languages: American English
- Released: 2026-07-23
- Data updated: 2026-08-03
- User reviews in markdown: https://appshunter.io/ios/app/electric-ref-wire-size-and-fill/id6791592027/reviews.md

## What is Electric Ref?

Type the amps, get the wire size. Pick a conduit, see how many conductors fit. Electric Ref answers the questions electricians ask every day — in three taps, fully offline.

SIZE WIRES CORRECTLY
- Amps to conductor size with temperature correction, conductor bundling adjustment and termination limits applied automatically
- Copper and aluminum, 60/75/90°C insulation
- Small-conductor breaker caps built in
- Every answer shows WHY — the code articles and factors behind it

CONDUIT & BOX FILL
- Max conductors for EMT, RMC, IMC, PVC 40/80, ENT, FMC, LFMC and more
- THHN, XHHW, TW/THW wire types
- Box fill with device, clamp and ground allowances

MORE FIELD TOOLS
- Voltage drop (DC and AC methods, any power factor, conduit material)
- Motor full-load current, conductor and breaker sizing
- Equipment grounding and grounding electrode conductor sizes
- Transformer currents, Ohm's law wheel

REFERENCE CHARTS
- Hole saw and knockout sizes (triple-checked)
- NEMA plug and receptacle configurations
- Motor starter sizes, wire color codes
- Burial depths, conduit support spacing, wire properties

BUILT FOR THE FIELD
- 100% offline — works in basements, new construction, anywhere
- Big glove-friendly controls, screen stays awake
- No account. Your calculations never leave your phone.

ONE-TIME PURCHASE
The free version includes the Ohm's law wheel, daily wire sizing and core reference charts. Electric Ref Pro is a single one-time purchase that unlocks every calculator and chart.

No subscription. No ads. No feature removals. Ever.

Values are based on the National Electrical Code®. Reference only — always verify with your locally adopted code edition and AHJ. NEC is a registered trademark of the National Fire Protection Association, which does not endorse this app.

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Electric Ref Pro | $19.99 | one-time |



## Version history (last 2 releases)

### 1.0.1 — 2026-08-02

Stability and reliability improvements.

### 1.0.0 — 2026-07-23

No release notes.

## More apps by Gun woo Kim

- [picswap - picture swap](https://appshunter.io/ios/app/picswap-picture-swap/id6456039579)
- [mubo - dance formation editor](https://appshunter.io/ios/app/mubo-dance-formation-editor/id6753949227)
- [LinePrompter](https://appshunter.io/ios/app/lineprompter/id6784582453)
- [Conduit Bender: Bend Calc](https://appshunter.io/ios/app/conduit-bender-bend-calc/id6786548483)
- [Tape Calc: Feet Inch Fraction](https://appshunter.io/ios/app/tape-calc-feet-inch-fraction/id6786612707)
- [Pipe Calc: Pipefitter Offsets](https://appshunter.io/ios/app/pipe-calc-pipefitter-offsets/id6786981763)

All apps by Gun woo Kim: https://appshunter.io/developer/1700263119

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-03.*