Voltly
The whole drawer, one tool.
Voltly is the electrician's field calculator and NEC reference — voltage drop, wire ampacity, conduit & box fill, conduit bending, Ohm's law, motor full-load amps, unit converters, and common code tables — fast, glove-friendly, and fully offline. One precise instrument-panel app that replaces a drawer full of single-purpose paid tools, with the formula and NEC article shown on every result.
Voltly
productivity
The whole drawer, one tool
What you get
Voltly was built for exactly this.
The core features that make Voltly different from the generic alternatives.
Voltage Drop — 1Ø/3Ø, copper or aluminum, % drop with an upsize suggestion when you're over 3%.
Ohm's Law / Power Wheel — enter any two of V, I, R, P and Voltly solves the rest.
Wire Ampacity — NEC 310.16 conductor sizing by size or by load, with the standard breaker.
Conduit & Box Fill — Chapter 9 fill % and 314.16 cubic-inch capacity, with pass/over status.
Conduit Bending — offset, three-point saddle and 90° stub-up with a clear diagram.
Motor FLC — full-load amps with 125% conductor and 250% OCPD sizing.
Converters — power (A·W·VA·kVA) and wire size (AWG ↔ mm² ↔ cmil).
Offline NEC reference — ampacity tables, wire color codes and cheat-sheets, on your phone with no signal.
Every answer cites its formula and NEC article — so you can show your work to the inspector.
A look inside
See it in your hands.
A note from the studio
“Electricians work with gloves on, in bad light, in dead zones — and they pay for a drawer of dated single-purpose apps. We built one quality instrument that's fast, correct, fully offline, and actually nice to use on the job.”
How it works
Three steps. No account. No tracking.
01
Pick a calculator
A clean grid of all eight calculators — two free, the rest unlocked once with Voltly Pro. Big, glove-friendly tap targets.
02
Enter the job
Segmented controls, scrollable size pills and −/+ steppers — no fiddly keyboard. The result updates live as you go.
03
Read the answer
A big, authoritative readout with the status (within 3%, over, etc.), the formula, and the NEC article it derives from.
04
Save it to a job
Keep results organized by site, panel or circuit. Everything lives on your phone — no account, no signal needed.
From the journal
Notes on the practice.
- 01
Voltage Drop Calculator: Sizing Conductors So You Pass the First Time
Undersized conductors fail inspection and starve equipment. Here's the NEC voltage-drop math, the 3% rule, and how to size a run right the first time — in seconds, offline.
2026-06-11
6 min read
- 02
The Calculation Habit That Separates a Clean Job From a Callback
A field workflow for electricians: when to run the numbers, what to calculate before you leave the truck, and how a calculation habit prevents costly callbacks.
2026-06-11
8 min read
- 03
One App Instead of a Drawer: The Offline Electrician Calculator
Conduit bending, ampacity, box fill, Ohm's law — most electricians own a half-dozen single-trick paid apps. Here's the case for one offline tool that does all of it.
2026-06-11
5 min read
- 04
EMT, IMC, or Rigid: Choosing the Right Conduit
A decision guide to EMT vs IMC vs rigid metal conduit: how wall thickness, connection method, and location decide which raceway belongs on your job.
2026-06-07
8 min read
- 05
Sizing a Feeder to a Detached Garage 150 Feet Away
Walk through feeding a detached sub-panel: how ampacity, voltage drop over distance, and the four-wire grounding rule all decide the conductor for a long feeder.
2026-06-03
9 min read
The dispatch
A dispatch from the studio.
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