A pocket reference for electricians and electrical engineers, Elec Ref provides a set of convenient utilities for reference on the job or on the go.

• Wire gauge calculator selects an appropriate wire gauge based on wire type, current, and environmental temperature.
• Parallel conductors determines the required number of conductors for a load and wire size.
• Conduit size calculator determines the minimum conduit diameter required for a series of wires.
• Transformer sizing calculator helps you buy the right transformer for your load, voltage, and phases.
• Resistor color code utility identifies the ohms, tolerance, and temperature coefficient based on a resistor's color bands.
• Motor amps reference gives typical Full Load Amps for standard motors.
• Motor horsepower calculator determines a motor's hp based on its voltage, efficiency, and amps. Also typical FLA values for electric motors.
• RJ45 Ethernet plug wiring reference.
• NEMA Plugs reference, locking and non-locking plugs to 60 amps.
• Standard wire colors for low voltage, 3 phase, telephone, British Automotive, bladed fuse color codes
• 25/50 pair color codes for telephone cables
• Wire types defined for more than 20 types including THHN, THWN, MTW, and all the major types.
• Thermocouple wire reference for 12 different types
• OptiCut cut optimization: how best to get a series of wire cuts out of a combination of partial spools and how many new spools you'll need to buy.
• Ohm's Law feature does all the permutations of V=IR and calculates Power as well.
• Voltage Drop calculator
• Voltage Unbalance calculator

Please share your ideas for additional functions at our website.
If you like Elec Ref please leave us good feedback on the iTunes store!

What’s New

Version 1.27

Fixed bug with Transformer sizing when calculating 3 phase sizes.
Thanks Mike B. for pointing this out!

Ratings and Reviews

2.9 out of 5
113 Ratings
113 Ratings
Greg76823 ,

Unavailable with IOS update

Updated phone to iOS 11.1 and now the app I paid for does not work and is showing it needs an update by developer. Great app otherwise, until you update your device then the app does not work. Hoping this issue gets fixed soon!

haillecoyote ,

Nice App, Needs Work

The following do not work; Motor Horsepower, Ohms Law, Opticut: Cut Optimization, Voltage drop, and Voltage Unbalance. Basically anything requiring numerical entry causes the numerical keypad to appear, then there is no way to eliminate the numerical keypad once the value has been entered. There is no way to complete the calculation or get out of the value field. The Opticut has no way of entering values at all. Would be very nice to enter custom amperage and voltage values rather than relying on 5 amp increments. A good idea poorly implemented. iPhone 6 running os 9.1

edenorchestra ,

Will there be an update?

I am an EE and this tool is a great addition to my arsenal. Its well rounded for design as well as field work. I looked around for something like this for a while. I have no regrets spending 5 bucks on it. Hoping there’s an update


Trunnion, LLC
2 MB
Requires iOS 5.0 or later. Compatible with iPhone, iPad, and iPod touch.
Age Rating
Rated 4+
© 2013 Trunnion LLC


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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