Estimate your monthly electricity bill by adding every appliance in your home along with its wattage, quantity, and daily usage hours. This tool is for general estimation only — your actual bill may include fixed charges, taxes, and slab-based rates set by your electricity provider.
Appliance
Watt
Qty
Hours/day
How to Use the Electricity Bill Calculator
List every appliance you want to include, with its wattage, quantity, and average hours of use per day.
Set the number of days per month and your electricity rate per unit (kWh).
Click "Calculate Bill" to see total units consumed and the estimated cost.
From Watts to Units to Rupees
One "unit" on an Indian electricity bill is one kilowatt-hour (kWh): 1,000 watts used for one hour. For each row the calculator works out watts × quantity × hours per day × days, divides by 1,000 to get units for the month, then adds the rows. The estimated cost is simply total units × the single rate you enter.
Worked Example with the Default Rows
Appliance
Working
Units per month
Fan
75 W × 1 × 10 h × 30 ÷ 1,000
22.5
TV
120 W × 1 × 5 h × 30 ÷ 1,000
18
AC
1,500 W × 1 × 6 h × 30 ÷ 1,000
270
Total
310.5
At ₹8 per unit the estimate is 310.5 × 8 = ₹2,484. Notice that the AC alone accounts for 87% of the units, which is typical in summer. Cutting its use by one hour a day saves 45 units, or ₹360 at the same rate.
Slab Tariffs and Your Effective Rate
Most Indian electricity boards charge domestic consumers by slabs, where the price per unit rises as monthly consumption goes up. The calculator uses one flat rate, so the most accurate figure to enter is your average rate: the energy charge on a recent bill divided by the units billed.
As an illustration only, take a made-up tariff of ₹4 for the first 100 units, ₹6 for the next 100 and ₹8 for everything above 200. For 310.5 units the energy charge would be 400 + 600 + 884 = ₹1,884, an average of about ₹6.07 per unit. Real slab boundaries, rates and whether the slabs apply to all units or only the excess differ by state and change with each tariff order.
Your bill will also include items this tool leaves out, such as a fixed or demand charge based on sanctioned load, electricity duty levied by the state, fuel or power purchase cost adjustment, and meter rent. Some states also give a subsidy or a free allowance of units to eligible households. Your board's website or tariff order lists the current figures.
Getting a Realistic Estimate
Appliances with a thermostat, such as fridges, ACs and geysers, do not draw their full rated power all the time. Entering rated watts × hours switched on overstates their use. For a fridge, use the yearly kWh printed on its BEE star label instead: divide it by 8,760 hours and multiply by 1,000 to get its average watts, then enter that with 24 hours a day. A fridge rated at 250 kWh a year averages about 29 W, or roughly 20.5 units in 30 days.
For an inverter AC, the running power after the room cools down is usually well below the rated figure. If the AC averages 60% of 1,500 W over 6 hours, enter 900 W and you get 162 units instead of 270.
Match the days to your billing cycle. Many boards bill every two months, so set about 60 days to compare with such a bill.
Compare the result with the units on your meter reading. If your estimate is much lower, you have probably missed an appliance or underestimated hours.
Frequently Asked Questions
Units (kWh) = Watt × Quantity × Hours/day × Days ÷ 1000. For example, a 75W fan used 10 hours a day for 30 days uses 75 × 10 × 30 ÷ 1000 = 22.5 units.
No. This estimates only the energy cost (units × rate). Most electricity providers also add fixed/meter charges, taxes, and sometimes slab-based rates that increase per unit as consumption rises — check your actual bill or provider's tariff for those.
Take a recent bill and divide the energy charge by the number of units billed. That gives your average rate under your state's slabs. If you want an all-in figure including fixed charges and duty, divide the total bill amount by the units instead.
Yes, a little. TVs, set-top boxes, chargers and microwave clocks draw a few watts when switched off by remote. To include it, add a row with the standby wattage and the hours the device sits idle. Switching off at the socket removes it.
Common reasons are fixed charges and electricity duty, higher slab rates once usage crosses a threshold, a billing period longer than the days you entered, or appliances left off the list, such as a geyser, water pump or iron.