Most "my bill jumped" stories have one of three causes: the rate went up, the billing period got longer, or the household used more energy. Only the last one is something an appliance or a draft can explain. These guides help you tell them apart using the two numbers every bill prints, kWh and days, before you spend anything.
If you already know your usage went up, the electricity cost calculator turns a suspected appliance into a dollar figure you can check against the bill.