In WattPayoff, open your recent bills and choose a billing cycle; the app analyzes exactly the dates PG&E billed you, so the usage matches the bill. You can see that cycle's usage pattern and what it would have cost on other plans.
Why analyze a single billing cycle instead of a year?
To explain one bill. A billing cycle lines up with the bill you received, so a jump is easy to trace: a heat wave, a new EV, guests, or a change in PG&E's prices. For choosing a plan, the full 365 days is the fairer view.
Frequently asked questions about billing cycles
Why don't my billing cycles start on the 1st of the month?
PG&E bills on your meter-reading schedule, so cycles usually run about a month from your read date, not calendar month to calendar month.
Why did one bill cover more days than usual?
Billing cycles vary in length. The bill detail shows the number of billing days.