Is this Electricity Bill calculator free?

Yes — completely free with no registration required. All calculations happen instantly in your browser.

Yes — all calculations happen in your browser. NerdyTools does not store or transmit any of your inputs. Your data never leaves your device.

How accurate is this Electricity Bill calculator?

This calculator uses established formulas and verified figures checked against official sources.

Does this work on mobile?

Yes — fully responsive and works on any modern browser on desktop, tablet, or mobile. No app download needed.

⚡ Home & Energy

Electricity Bill Calculator

Work out your electricity cost from your usage, or find out how much any appliance costs to run. See the cost per day, week, month, and year.

⚡

Choose a mode: estimate a full bill from your kWh usage, or find the running cost of a single appliance from its wattage. Enter your electricity rate and get the cost across every period.

Electricity Used

kWh

From your meter or bill, for the period below.

Billing Period

Usage Rate

Price per kWh (check your bill — often $0.25–0.45).

Daily Supply Charge (optional)

Fixed daily connection fee on most bills.

Estimated Bill

Per Day

Per Week

Per Month

Per Year

⚠️ Estimate only. Real bills vary with tiered/time-of-use tariffs, peak and off-peak rates, seasonal usage, taxes, discounts, feed-in credits (solar), and demand charges. Use your actual per-kWh rate and supply charge from your bill for the closest result. This is a guide, not your exact bill.

What is an Electricity Bill Calculator?

An electricity bill calculator estimates how much your power costs — either as a full bill from your total energy usage, or as the running cost of a single appliance. Electricity is billed per kilowatt-hour (kWh), so by combining your usage with your rate (and the fixed daily supply charge most providers add), you can work out what you're paying and where the money goes. This tool does both: estimate your whole bill, or find out exactly how much that heater, air conditioner, or fridge costs to run.

Understanding your electricity costs is the first step to reducing them. Seeing the yearly cost of a power-hungry appliance often makes the case for using it less, replacing it, or shifting it to off-peak times.

How is an Electricity Bill Calculated?

Your bill has two main parts: a usage charge (what you consume, in kWh, times the rate) and a fixed supply charge (a daily fee for being connected). For an appliance, the energy it uses is its power in kilowatts multiplied by the hours it runs.

Usage Cost = kWh used × rate per kWh
Supply Cost = daily charge × number of days
Total Bill = Usage Cost + Supply Cost

Appliance kWh/day = (Watts ÷ 1000) × hours per day
Appliance Cost = kWh/day × rate × days

How to Use This Calculator

For Estimate My Bill, enter your total electricity used (in kWh, from your bill or meter), the billing period, your usage rate per kWh, and the daily supply charge if you want it included. For Appliance Cost, enter the appliance's power in watts, how many hours a day and days a week you use it, and your rate. Either way, you'll get the cost per day, week, month, and year.

What is a Kilowatt-Hour (kWh)?

A kilowatt-hour is the unit electricity is sold in. It's the energy used by a 1,000-watt (1 kW) appliance running for one hour. So a 2,000-watt heater uses 2 kWh per hour, while a 100-watt device running for 10 hours also uses 1 kWh. Your bill multiplies your total kWh by the rate. Knowing an appliance's wattage and how long it runs is all you need to work out its energy use and cost.

💡 The biggest electricity users in most homes are heating and cooling, hot water, and anything that heats: electric heaters, air conditioners, clothes dryers, ovens, and kettles. Low-wattage devices left on (like phone chargers or standby electronics) cost far less than people fear — focus on the high-wattage, long-running appliances to cut your bill.

Typical Appliance Power Usage

Appliance	Typical Power	Notes
Electric heater	1,500–2,400 W	High cost when run for hours
Air conditioner	1,000–3,500 W	Varies hugely by size
Clothes dryer	2,000–3,000 W	Expensive per load
Refrigerator	100–250 W	Runs 24/7 but cycles on/off
LED light bulb	5–15 W	Very cheap to run
TV	50–150 W	Modest cost

How to Lower Your Electricity Bill

Target the big users: heating, cooling, and hot water dominate most bills — small changes here save the most.
Use off-peak rates: if you're on a time-of-use tariff, run dishwashers, washing, and charging overnight.
Switch to LED lighting and efficient appliances with good energy ratings.
Adjust the thermostat: a degree or two on heating and cooling makes a real difference.
Compare retailers and plans — the per-kWh rate and supply charge vary a lot between providers.

Understanding Tariffs and Time-of-Use Pricing

Many electricity plans charge a single flat rate per kWh, but others use time-of-use pricing, where electricity costs more during peak hours (typically late afternoon and evening) and less off-peak (overnight). Some plans also have tiered rates that rise after you pass a usage threshold. This calculator uses a single rate for simplicity — for the most accurate estimate, use your average or applicable rate, and consider shifting heavy usage to cheaper periods if you're on a time-of-use plan.

Frequently Asked Questions

How do I calculate my electricity bill?

Multiply your electricity usage in kWh by your rate per kWh, then add the daily supply charge times the number of days in the period. For example, 900 kWh × $0.30 = $270, plus a $1/day supply charge over 91 days ($91) = $361 for the quarter. Enter your figures above and the calculator does it instantly, with daily, weekly, monthly, and yearly costs.

How much does it cost to run an appliance?

Take the appliance's power in watts, divide by 1,000 to get kilowatts, multiply by the hours you use it to get kWh, then multiply by your rate. A 2,000W heater for 5 hours uses 10 kWh; at $0.30/kWh that's $3 a day, or about $90 a month if used daily. Use the Appliance Cost mode above to calculate any device.

What is a kWh?

A kilowatt-hour (kWh) is the unit of energy your electricity is billed in — the energy a 1,000-watt appliance uses in one hour. A 2,000W appliance uses 2 kWh per hour; a 500W appliance uses 0.5 kWh per hour. Your total kWh for the billing period, times your rate, gives your usage charge.

What uses the most electricity in a home?

Heating and cooling typically use the most, followed by hot water heating, then high-wattage appliances like clothes dryers, ovens, and dishwashers. Anything that produces heat (heaters, kettles, dryers) draws a lot of power. Lights and electronics usually use far less than people expect. Focus on the big, heat-producing appliances to cut costs.

What is the supply charge on my bill?

The supply charge (or service/connection charge) is a fixed daily fee you pay just to be connected to the grid, regardless of how much electricity you use. It's typically around $1 per day but varies by provider and region. Even with zero usage, you'd still pay the supply charge, which is why it's included as an option in this calculator.

Why is my actual bill different from this estimate?

Real bills can differ due to tiered or time-of-use tariffs (peak/off-peak rates), seasonal usage changes, taxes and levies, discounts, solar feed-in credits, and demand charges. This calculator uses a single flat rate for simplicity. For the closest estimate, use your exact per-kWh rate and supply charge from a recent bill.

How can I reduce my electricity bill?

Target the biggest users: reduce heating and cooling (adjust the thermostat a degree or two), shift heavy usage to off-peak times if you're on a time-of-use plan, switch to LED lighting and efficient appliances, and compare electricity retailers — the rate and supply charge vary significantly between plans. Use the appliance mode to find your costliest devices.

Is my data private?

Yes. The calculator runs entirely in your browser — nothing you enter is uploaded or stored. It's instant, private, and works offline once loaded.