Skip to main content
Tool · Panel Amperage Calculator

What service size does your house really need?

* A two-minute calculator built on Ontario Electrical Safety Code Rule 8-200 — the same load calculation your electrician runs before quoting a panel upgrade.

01Current panelIn progress

What's your current main panel size?

The amperage printed on your main breaker — usually 100 A or 200 A on newer homes, 60 A on older ones. Pick "Not sure" and we'll skip the comparison at the end.

How do I find my panel size?
MAIN30

The wide switch at the top (copper) is your main breaker.

  1. Find your panel — usually in the basement, garage, utility room, or a hallway closet. It's a grey metal door.
  2. Open it. The biggest switch — often alone at the top or side — is the main breaker.
  3. The number stamped on it (60, 100, 125, 200) is your panel size. Can't find it? Pick Not sure — we'll confirm from the photos you send.

Answer above to continue.

Estimated load
0A
Step
1 / 7