Voltkit: NEC Conduit Fill Calc
Conduit Bending & Voltage Drop
Only for iPhone
Free · In‑App Purchases · Designed for iPhone. Not verified for macOS.
iPhone
Every result cites its exact NEC 2023 table — 21 offline calculators for voltage drop, conduit fill, wire size, ampacity and more, built for working electricians.
Voltkit is a precision NEC calculator built for working electricians — fast, accurate, and 100% offline. Every result cites the exact NEC 2023 table or formula behind it, so you can trust the number on the job and back it up to an inspector.
— 21 PRO CALCULATORS —
• Voltage Drop — approximate-K and exact Chapter 9 (Table 9 R/X) methods
• Conduit Fill — 10 raceways and every insulation, Chapter 9 Table 4, with the Note 7 same-size round-up
• Wire Size — the smallest conductor that meets ampacity, voltage drop and the 240.4(D) small-conductor limits, with an optional 310.12 dwelling-service rule
• Wire Ampacity — Table 310.16 with ambient and bundling adjustments, plus free-air
• Box Fill — NEC 314.16 with a full standard-box picker, per-device yoke sizing and the quarter allowance for each EGC past four
• Conduit Bending — 90° stub-up, offset, rolling, and saddle, with a scaled bend diagram
• Bend Length, Segment Bend, Bend Total, and Concentric — a full pipe-bending suite
• Ohm's Law and AC Power — watts, VA, and power factor, single- and three-phase
• Grounding — EGC (250.122), GEC (250.66), and 250.122(B) upsizing
• Dwelling Load — optional and standard methods (Article 220)
• Motor — full-load current, conductor, overload, and OCPD (Article 430)
• Plus Transformer, Pull Box, Parallel Sets, Motor Feeder, Power-Factor correction, and Appliance Demand
— BUILT FOR THE FIELD —
• Works entirely offline — every NEC table lives on your device, no signal required
• Show Calculation — open any result into clear, step-by-step math
• Save jobs and reopen them later from your calculation history
• Built-in NEC reference tables: ampacity, conduit fill, box fill, conductor properties, and more
• NEMA receptacle and conductor color-code references
— WHY ELECTRICIANS TRUST VOLTKIT —
Every calculation is derived from a published NEC 2023 table or formula and checked against authoritative worked examples (Mike Holt, Ugly's, NEC Annex C). No ads, no clutter, no internet required — just a clean, precise instrument that respects your trade.
— FREE, WITH OPTIONAL PRO —
Voltkit is free to use: every calculator gives you a complete, NEC-cited result and full worked steps. Voltkit Pro unlocks the advanced options for commercial and industrial work — three-phase, exact-impedance voltage drop, free-air ampacity, every raceway and insulation, larger conduit, box and parallel runs, over-1000 V transformers, and the full standard load calc — plus unlimited saved calculations. Prices may vary by region.
Built in the US for NEC 2023. Canadian CEC, BS 7671, and AS/NZS 3000 code packs are on the roadmap.
Voltkit is an independent tool and is not affiliated with or endorsed by the NFPA.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
• Conduit Fill: Chapter 9 Note 7 round-up for same-size wires, so 22 #14 THHN in 3/4" EMT now reads OK, as in Annex C.
• Box Fill: each device yoke is sized by the largest wire on that device (314.16(B)(4)); studs and hickeys count once per type; each EGC past four adds ¼ (314.16(B)(5)). The old version could under-count a box with 5+ grounds.
• Wire Size: 240.4(D) small-conductor limits, plus an optional 310.12 83% rule for dwelling services.
• Support: hello@voltkitapp.com
The developer, Chirag Arora, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- Contact Info
- Identifiers
- Usage Data
- Diagnostics
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Chirag Arora
- Size
- 46.2 MB
- Category
- Utilities
- Compatibility
Requires iOS 15.0 or later.
- iPhone
Requires iOS 15.0 or later. - iPod touch
Requires iOS 15.0 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- Voltkit Pro - Yearly $19.99
- Voltkit Pro - Monthly $4.99
- Copyright
- © Chiaro Apps