Electrical Panel Capacity Calculator
Calculate if your electrical panel has enough capacity for additional circuits and loads
About this calculator
The Electrical Panel Capacity Calculator helps homeowners and electricians determine if their electrical panel can safely accommodate new circuits or appliances. By calculating your panel's current load versus its total capacity, this tool prevents dangerous overloading situations that can cause fires or electrical failures. It's essential for planning home additions, installing new appliances, or upgrading electrical systems while ensuring code compliance and safety standards are met.
How to use
Enter your electrical panel's total amperage rating (typically 100, 150, or 200 amps) and list all current circuits with their amperage ratings. The calculator will sum your existing load and compare it to your panel's capacity, showing available space for additional circuits and recommending safe loading percentages.
Frequently asked questions
What percentage of panel capacity should I use?
Most electrical codes recommend using no more than 80% of your panel's total capacity for safety and to prevent overheating.
How do I find my panel's amperage rating?
Check the main breaker switch or look for a label inside the panel door that shows the total amperage rating.
Can I add circuits if my panel shows 100% capacity?
No, you'll need to upgrade to a larger panel or remove existing circuits before adding new ones safely.