Every month a number arrives: $126.40, due in three weeks. It doesn’t say which appliance earned which dollar — just the total, take it or leave it. PowerBill exists for the ten minutes after you look at that number and wonder where it went.

What the site does

The estimator on the home page is a per-appliance ledger: fifteen common devices, each with quantity, hours-per-day and days-per-month, summed into monthly kWh and priced at whatever rate you bring. It answers the questions bills actually raise — what does the AC cost me? would LEDs pay back? is the old garage fridge the problem? — and it shows its work: every row prints the wattage it assumes and the range that wattage typically spans.

The method, and its honest limits

The math is the one-line formula every meter runs — watts × hours ÷ 1,000 — so the estimate is only as good as two inputs: the wattage and the hours. We supply typical wattages drawn from the usual public references (DOE and ENERGY STAR consumption figures, FTC EnergyGuide ranges, nameplate data); where a device cycles — a fridge, a water heater — the row says so and uses a duty-cycled figure instead of pretending the nameplate runs all day. You supply the hours, which is the part we can’t know. The result is a model with the assumptions printed next to it — useful for ranking and budgeting, not a substitute for your meter.

What the site doesn’t do

No account linking, no utility login, no uploading your bill, no smart-home integration. The estimator runs entirely in your browser tab, which is a deliberate design: your appliance list is exactly the kind of mundane data that doesn’t need to exist on anyone’s server, so it doesn’t.

Around the neighborhood

PowerBill lives on nxtolerance.com alongside sibling tools like ResCal (resize geometry) and PixelCalc (pixel density). Same philosophy across the cluster: one page, honest math, nothing phoned home.

Corrections

Wattage figures are ranges by nature, but a wrong typical value is still wrong — if your device’s real-world draw contradicts a row here, or an article misstates a figure, the contact page is the fastest way to get it fixed.