Electricity Cost Calculator
Estimate your next electricity bill by combining kWh usage, tariff splits, and daily supply charges. Adjust the sliders to mirror time-of-use plans or single rate offers and see the monthly and annual cost instantly.
Billing period inputs
Tariff split
Adjust the percentage split if you know how much usage falls into each tariff. The percentages do not need to equal exactly 100%, but the calculator will highlight any gaps.
Estimated bill
$547.60
for a 92-day billing period
Monthly average
$178.57
Annualised cost
$2,172.54
Average usage rate
$0.28 / kWh
Usage breakdown
Peak
960 kWh · $0.32 / kWh
$307.20
Shoulder
400 kWh · $0.24 / kWh
$96.00
Off-peak
240 kWh · $0.18 / kWh
$43.20
Supplier charges
- Supply charge (92 days)$101.20
- Usage charges$446.40
- Total estimated bill$547.60
Tip: Update supply and usage rates whenever retailers announce new reference price changes.
How to interpret the results
Compare the estimated bill against each retailer's quote. If the total cost is higher than expected, tweak the tariff split or lower the usage number to match your household habits.
The monthly average is handy when lining up energy plans with other recurring expenses. Use the annualised cost to track how much a switch could save you over 12 months.
Want to keep electricity and gas with a single provider? Pair this calculator with our gas bill estimator before locking in a dual fuel bundle.
FAQ
Electricity calculator questions
Where do I find my usage numbers?+
Check the back of your last electricity bill. Retailers list the total kWh for the billing period and often provide a daily average. Enter either the exact usage or an estimate based on your meter reads.
How accurate are the supply and usage rates?+
The calculator uses whatever rates you enter. Copy the supply charge (usually expressed in cents per day) and usage tariffs (cents per kWh) from each retailer you compare. Update the values whenever reference prices change.
What if I only have a single rate plan?+
Set the peak percentage to 100% and leave shoulder/off-peak at 0. This mirrors a flat tariff and still calculates your bill, supply charge, and annual equivalent costs.