Electric Bill Calculator
kWh
$
$
%
Total Bill$126.26
Energy Charge$108.00
Tax$8.26
Effective Rate / kWh$0.1403
The Electric Bill Calculator builds up a complete monthly power bill rather than the cost of running a single device. It bills your kWh usage against either a flat rate or a tiered block schedule where each band of consumption is priced separately, then layers on the fixed service charge your utility adds every month and a percentage tax. The result is the full total plus your true effective rate per kWh once every line item is included.
Formula
energy = Σ(kWh_in_tier × tier_rate); subtotal = energy + fixed; total = subtotal × (1 + tax/100)
- kWh_in_tier
- Usage that falls within each rate block
- tier_rate
- Price per kWh charged in that block
- fixed
- Flat monthly service or connection charge
- tax
- Tax percentage applied to the subtotal
How it works
- Enter your monthly usage in kWh, then choose a flat rate or define up to three tiered blocks with their kWh limits and per-kWh prices.
- Each tier is billed only on the kWh that fall inside its band, so the first block fills before the next rate applies — exactly how block pricing works on a utility bill.
- Your fixed service charge is added to the energy charge, tax is applied to that subtotal, and the calculator divides the grand total by usage to show your effective all-in rate.
Worked example
900 kWh on a three-tier plan: 0.12/kWh to 300, 0.18 to 600, 0.26 above, plus a $10 charge and 7% tax.
- Tier 1: 300 × 0.12 = $36.00.
- Tier 2: 300 × 0.18 = $54.00; Tier 3: 300 × 0.26 = $78.00; energy = $168.00.
- Subtotal = 168 + 10 = $178.00; tax = 178 × 0.07 = $12.46; total = $190.46.
Total bill $190.46, with an effective rate of about $0.2116 per kWh.
Frequently asked questions
- How is this different from a basic electricity cost calculator?
- A basic appliance calculator multiplies one device’s watts by hours and a single rate. This tool models a whole bill: tiered block rates across all usage, the monthly fixed charge, and tax to reach the real total.
- What are tiered or block rates?
- Many utilities charge a low rate for the first block of kWh and higher rates as you use more. Each tier is billed only on the kWh inside its band, so heavy use is penalized at the top tier rate.
- What is the fixed or service charge?
- It is a flat fee billed every month regardless of usage, covering metering and grid connection. It is added before tax and is why a low-usage month still has a meaningful minimum bill.
- Why is my effective rate higher than my base rate?
- The effective rate divides the full total — energy, fixed charge and tax — by your kWh. Because fixed fees and tax spread across your usage, the all-in rate per kWh sits above the headline energy rate.