About These Calculators
Electrical calculators for electricians, engineers, and DIYers. Size wires, calculate voltage drop, determine breaker sizes, and plan electrical panels.
Electrical Calculators
14 toolsBreaker Size Calculator
Calculate the correct circuit breaker size for your load
LED Resistor Calculator
Calculate the correct resistor for LED circuits
Amps to Watts Calculator
Convert between amps, watts, and volts
Power Factor Calculator
Calculate real, reactive, and apparent power
Electrical Conduit Fill Calculator
Calculate conduit fill capacity based on wire gauge, count, and conduit size per NEC standards
Transformer Sizing Calculator
Calculate transformer kVA requirements based on load voltage and amperage
Motor Horsepower Calculator
Calculate electric motor horsepower from torque and RPM or voltage and amperage
Electrical Load Balancing Calculator
Balance electrical loads across panel phases to prevent overloading and tripped breakers
Ground Wire Size Calculator
Determine the correct grounding conductor size per NEC Table 250.122
Electrical Panel Capacity Calculator
Calculate total electrical panel load and remaining capacity for new circuits
Three Phase Power Calculator
Calculate three-phase power, current, and voltage for industrial and commercial electrical systems
Emergency Generator Load Calculator
Size an emergency or standby generator based on your essential electrical loads
Battery Life Calculator
Calculate battery runtime from capacity and load
Wire Ampacity Calculator
Look up maximum amperage for wire gauge sizes
Frequently Asked Questions
Are these electrical calculators free?
Yes, all 14 calculators are completely free with no signup required. They run entirely in your browser — no data is sent to any server.
How accurate are these calculators?
Our calculators use industry-standard formulas and are regularly updated. However, they provide estimates — always verify critical calculations with a professional in the relevant field.
Can I use these calculators on my phone?
Yes, all calculators are mobile-responsive and work on any device with a web browser. No app download needed.
Do you save my calculations?
No. All calculations happen in your browser. We don't store any of your inputs or results. Your data stays on your device.
Can I embed these calculators on my website?
Select calculators offer embed codes that you can copy and paste into your website or blog. Look for the "Embed This Calculator" section on individual tool pages.