Electrical Pro Tools

Work the numbers.
Get back to the job.

Five electrical field calculators that show their work, plus conduit bending and Journeyman & Master exam preparation.

Phone & Desktop Calculations Explained mm / in Toggle Journeyman & Master Copper & Aluminum Parallel Run Support
Get Bending & Study — $34.99 Use Free Field Calculators →

Free field calculators. Paid bending and study apps from $14.99. One-time purchases, no subscription.

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Conduit Bending Pro
Bending marks you can read straight from your tape — inches and fractions by default, with a millimetre option and full conduit data.
Offset bends — mark distance + shrinkage
Concentric bends — stagger marks + incremental bite technique
3-bend & 4-bend saddle calculators
EMT, IMC, RMC, PVC Sch.40/80, PVC Type A, ENT — 7 types
OD, ID, min bend radius, weight per metre
Global conduit selector feeds all calculators
Preview Bending Calculator →
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License Exam Study App
224 exam-quality questions covering everything from Ohm's Law to business taxes. Built by someone who held licenses in 38 states.
Study mode — instant feedback with NEC references
Timed test mode — configurable length & category
Progress tracking by category across sessions
Journeyman & Master content — filter by level
NEC edition changes — 1999 through 2023
Exam strategy tips — including point-weighting tricks
Preview Study App →
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Electrical Field Calculators
Five practical calculators for planning a run, checking a box, sizing conductors and working through electrical formulas. Results show the numbers behind the answer.
Conduit fill from ½ through 4 inches, including custom diameters
Box fill with mixed wires, grounds, devices and fittings
Ampacity, derating and parallel sets in separate raceways
Voltage drop with your target and smallest-size comparison
Ohm’s Law with worked formulas and repeat calculations
Single- and three-phase kW, kVA and power-factor conversions
Use Free Field Calculators →
Five field calculators

Go straight to the calculation you need.

Mixed conductors, equipment limits, parallel runs and load checks. All five are free to use in your browser. Each tool explains its method so you can review the result against the installation.

Conduit Fill

Compare raceways from ½ through 4 inches. Include insulated grounds and custom round-conductor diameters, then use the smallest fitting size.

Check conduit fill →

Box Fill

Add mixed wire sizes, grounding conductors, device yokes, clamps and fittings. See required volume, remaining space and the counting breakdown.

Check box volume →

Ampacity & Derating

Apply ambient and CCC factors, check terminal limits and continuous loads, and calculate equal parallel sets in separate raceways.

Check allowable ampacity →

Voltage Drop

Check copper or aluminum on single- or three-phase circuits. Set a drop target and compare conductor size or maximum run length.

Check voltage drop →

Ohm’s Law & AC Power

Enter two values and see the worked solution. Convert between current, kW and kVA, or calculate power factor for AC loads.

Solve electrical formulas →

Follow the calculation through

Move the CCC count from Conduit Fill into Ampacity, then carry conductor size and current per parallel set into Voltage Drop.

Open the full calculator suite →

Need bend layouts or exam preparation?

Conduit Bending Pro and the License Exam Study App are available together for $34.99, paid once.

See the Complete Bundle →

NEC reference methods for qualified electrical workers. Verify the adopted edition, local amendments, equipment listings and installation conditions. Field calculators require an internet connection to load; bending and study support offline use after installation.

Bending & study apps

Choose one app or get both in the bundle. Current prices are in US dollars and are one-time purchases.

Bending Calculator
$14.99
one-time purchase
  • Offset, concentric & saddle calculators
  • 7 conduit types, 12 trade sizes
  • Metric & imperial
  • Works offline on any device
Buy Calculator →
Study App
$24.99
one-time purchase
  • 220+ exam-quality questions
  • Journeyman & Master content
  • Study + timed test modes
  • Works offline on any device
Buy Study App →
One-time payment  ·  Instant download  ·  No subscription  ·  Secure checkout via Stripe
From the Desk of

Listen up, future spark wranglers! If you're an electrician—or dreaming to be one—you're about to hit a critical hurdle: the licensing exam. But don't sweat it; I'm here to guide you through the maze.

I've been knee-deep in this trade for over 60 years as a Professional Electrical Engineer, Master Electrician, and Electrical and General Building Contractor. I've built and inspected installations across the U.S., Canada, Ireland, the UK, and even the Philippines. Taught the National Electrical Code for the Associated Builders and Contractors, too. I'm not just a name; I've held my ground with NECA, BICSI, SAME, and countless other organizations. Whether it was rolling with IBEW or hustling as a non-union contractor, I know this industry inside and out. And you better believe I know what it takes to ace these exams—I've taken more than a few myself.

Thirty-eight states, to be exact.

The Hidden Trick No One Dares to Share

Let me tell you something crucial that flipped the script for me while living in Salt Lake City. I stumbled upon a testing company that administered licensing exams for most states. Instead of hopping from one state capital to another like some kind of license-hunting nomad, I decided to play it smart: I scheduled all my tests at their facility—at one point, I was cranking out two or three state tests in one sitting!

Here's the kicker: this testing company was pulling from the same question bank for every state. Once I caught wind of that, everything fell into place. Study the code until it's second nature, and forget about geographical limitations.

But let's be crystal clear—the National Electrical Code (NEC) is your Holy Grail. You need to know it inside and out—the specifics, not just the generalities. This is where preparation makes all the difference between success and floundering.


The Game-Changing Study App

We've crafted an exam prep app that pulls from my decades of experience. It's designed for both Journeyman and Master Electrician content, all based on the 2026 NEC—ideal whether you're prepping for your first exam or brushing up for continuing education.

Right now, this powerhouse app houses over 220 multiple-choice questions. Miss one? Don’t worry—it redirects you to the right answer with an explanation that’ll make it stick. We’re expanding it to include calculation-based questions too: load calculations, conductor sizing, conduit fill—the skills you’ll need to work through on paper anyway.

We’ll keep updating it as the code evolves, because staying ahead is what separates the pros from the amateurs.


Your Conduit Bending Calculator

Ever stared at those beautiful concentric bends and wondered how on earth they got laid out so perfectly? Most of us learned offsets from some flimsy laminated card and guessed our way through the rest. But there’s a smarter way.

Our conduit bending calculator gives you precise mark distances, stagger amounts, and bite spacings for creating perfect offsets, concentric bends, and saddles across every major conduit type—in both metric and imperial. It runs right on your phone and works offline at job sites. Say goodbye to guesswork; we’ve crunched the numbers for you.


What Does This Cost?

Here’s the deal: nothing substantial. We priced these tools so that every hardworking electrician can access them—because you’re the ones who need them most. Download both apps, use them to prep for your exam, then keep them handy for your daily grind.

After sixty years in this game, I can tell you: success in electrical work comes from continuous learning. These tools are engineered to help you do just that—learn, grow, and conquer.

— Charles BaldwinElectrical Pro Tools
What’s Included
224
Study Questions
18
Categories
7
Conduit Types
4
Bend Calculators
Conduit Bending Pro covers the mathematics most electricians learned from a laminated card — now extended to full conduit specifications across seven conduit types and up to twelve trade sizes. Switch between mm and inches at the tap of a button. The bending formulas are trigonometrically exact: mark distance = offset ÷ sin(θ) for offsets; shrinkage correctly explained with field method; stagger marks + incremental bite technique for true concentric bends; height ÷ sin(outer angle) for saddles.

Electrical Field Calculators include conduit fill through 4 inches, box fill, ampacity and derating with parallel sets, voltage drop, and Ohm’s Law with AC power conversions. Each result shows the method, applicable limits and the entered values. Use them on your phone or desktop, and move between the linked calculations as you plan a run.

The Study App covers every major category tested on Journeyman and Master electrician state exams: electrical theory, all major NEC articles, grounding and bonding, load calculations, motor circuits, hazardous locations, transformers, box fill, and — for Master candidates — business management, accounting, contracts, estimating, labor law, tax, and project management. The Exam Tips tab includes field-tested strategy from an electrician who held 38 state licenses simultaneously.
Note: These tools are for educational and field-reference use. Always verify calculations and code references against your current jurisdiction’s adopted NEC edition and local amendments. Exam content requirements vary by state — confirm with your state licensing board before your exam. NEC® is a registered trademark of the National Fire Protection Association.