What is an electricity bill calculator?
An electricity bill calculator estimates what you will pay for the power you use in a month. Enter the units shown on your meter – or the watts and hours of each appliance – and the calculator applies your state's slab rates, fixed charge and electricity duty to give you the bill amount with a slab-wise breakup. It is a handy electricity bill calculator for home use, for checking whether a new AC is worth it, and for spotting a wrong bill before you pay it.
Important: electricity tariffs in India differ by state and by DISCOM (distribution company), and change every year when the state regulatory commission issues a new tariff order. The default slabs in this tool are only an example. For an accurate result, copy the slab limits, per-unit rates, fixed charge and duty from your own bill or your DISCOM's website – whether that is BSES or Tata Power in Delhi, MSEDCL or Adani in Maharashtra, TANGEDCO in Tamil Nadu, KSEB in Kerala, BESCOM in Karnataka, UPPCL in UP, or the MP, Rajasthan, Punjab, Gujarat or West Bengal boards.
How to calculate electricity bill – step by step
- Find the units consumed. Subtract last month's meter reading from this month's reading. The difference is your consumption in units (kWh). This is how to calculate an electricity bill from a meter reading.
- Apply the slab rates. Most Indian DISCOMs use telescopic slabs: the first block of units is charged at a low rate, the next block at a higher rate, and so on.
- Add the fixed charge. A monthly charge per kW of sanctioned load or per connection, paid even if you use nothing.
- Add electricity duty and other levies. Usually a percentage of the energy charge, plus any fuel cost adjustment.
This calculator does all four steps. Pick Units consumed if you know your reading, or Appliance-wise usage to estimate from your appliances.
Electricity bill calculator formula
Bill = Σ (units in each slab × slab rate) + fixed charge + duty % × energy charge
For appliances, the units come from this formula:
Units (kWh) = Watts × Hours per day × Days ÷ 1000
- 1 unit = 1 kilowatt-hour (kWh) = 1,000 watts used for one hour
- Watts – the power rating on the appliance label
- Duty – the state electricity duty or tax percentage
How is electricity bill calculated – with example
Take 250 units in a month with these example slabs: 0–100 units at ₹3, 101–200 at ₹4.50, 201–400 at ₹6.50, above 400 at ₹8, a fixed charge of ₹100 and 5% duty.
| Slab | Units | Rate | Charge |
|---|---|---|---|
| 1–100 | 100 | ₹3.00 | ₹300.00 |
| 101–200 | 100 | ₹4.50 | ₹450.00 |
| 201–400 | 50 | ₹6.50 | ₹325.00 |
| Energy charge | ₹1,075.00 | ||
| Fixed charge | ₹100.00 | ||
| Duty 5% of energy charge | ₹53.75 | ||
| Total bill | ₹1,228.75 | ||
The average cost works out to about ₹4.92 per unit. Notice how only the units above 200 are billed at ₹6.50 – you don't pay the higher rate on all 250 units. That is the telescopic slab system most states use for domestic connections. A few tariffs are non-telescopic (once you cross a limit, all units are charged at the higher rate); if yours is one of them, set every slab rate to that single rate.
Electricity bill calculator by appliances
Choose appliance-wise usage to see where your units go. Typical wattages:
| Appliance | Typical power | Daily use | Units per month (30 days) |
|---|---|---|---|
| 1.5 ton AC (3-star inverter) | 1,200–1,500 W | 6 h | 216–270 |
| Refrigerator (double door) | ~150 W average | 24 h | ~108 |
| Ceiling fan | 50–75 W (BLDC 28–35 W) | 10 h | 15–23 |
| LED bulb | 9 W | 6 h | 1.6 |
| Geyser | 2,000 W | 1 h | 60 |
| LED TV | 60–100 W | 5 h | 9–15 |
| Washing machine | 500 W | 1 h | 15 |
With the default appliance values – a 1,500 W AC for 6 hours, a fridge, 300 W of fans and lights for 8 hours and 2,000 W of other appliances for 1 hour – the home uses 270 + 108 + 72 + 60 = 510 units in 30 days.
Electricity bill calculator for AC
An air conditioner is usually the single biggest item. A 1.5 ton AC drawing 1.5 kW for 8 hours a day uses 12 units a day, or 360 units a month. Because those units fall into the highest slabs, an AC can double a summer bill. Setting the thermostat at 24–26°C, using a 5-star inverter model and cleaning filters regularly cuts consumption noticeably.
What is electricity bill per unit?
The price per unit depends on your state, connection type and how many units you use. Domestic rates in India range from about ₹2–₹4 in the lowest slab to ₹7–₹10 in the top slab. Commercial and industrial connections (shops, offices, factories) pay higher rates plus a demand charge per kVA, so use the rates printed on your commercial bill to use this as an electricity bill calculator for commercial or shop connections. The result shows your effective average cost per unit, which includes fixed charges and duty.
Charges you may see on an Indian electricity bill
- Energy charge – units × slab rates.
- Fixed or demand charge – based on sanctioned load (kW) or a flat amount.
- Fuel cost adjustment (FCA / FPPCA) – a per-unit surcharge when generation fuel costs rise.
- Electricity duty / tax – a state levy, usually a % of the energy charge.
- Meter rent and subsidy – some states (like Delhi and Punjab) give free or subsidised units below a limit, which lowers the final amount.
Enter FCA as part of your per-unit rate, or add it to the fixed charge, to include it in the estimate.
Electricity bill calculator with solar
With rooftop solar on net metering, you pay only for net units: units imported from the grid minus units exported. Enter that net figure as the units consumed. A 3 kW rooftop system in most of India generates about 10–12 units a day, roughly 300–360 units a month, which can wipe out the bill of a typical home.
Electricity bill calculator for your state
The method is the same everywhere; only the numbers change. Use this page as an electricity bill calculator for Delhi, Maharashtra, Tamil Nadu, Kerala, Karnataka, Rajasthan, Punjab, Haryana, Gujarat, West Bengal, Odisha, Andhra Pradesh, Telangana, Jharkhand, Chhattisgarh, Goa, UP or MP by typing in that state's domestic slabs:
- Delhi (BSES Rajdhani, BSES Yamuna, Tata Power-DDL) – telescopic slabs plus a state subsidy on the lowest units.
- Maharashtra (MSEDCL, Adani Electricity, Tata Power, BEST) – slab energy charges plus a separate wheeling charge per unit; add the wheeling charge to each slab rate.
- Tamil Nadu (TANGEDCO, Chennai included) – bi-monthly billing, so enter two months of units and double the slab limits.
- Kerala (KSEB) – also bi-monthly, with different rates once usage crosses 250 units a month.
- Uttar Pradesh (UPPCL, Lucknow, Noida) and Madhya Pradesh (MP electricity boards in Bhopal, Indore and Jabalpur) – slab rates plus fixed charge per kW of load.
- Haryana (DHBVN, UHBVN, Gurgaon) and Rajasthan (Jaipur, Ajmer and Jodhpur discoms) – fixed charge depends on the slab you reach.
To estimate the electricity cost per year, check the yearly figure in the result or run the calculator for a summer month and a winter month and average the two.
Tips to reduce your electricity bill
- Stay within a lower slab – even 20–30 fewer units can move you out of the costliest slab.
- Replace old bulbs with LEDs and old fans with BLDC fans.
- Buy 5-star rated appliances; the extra price is often recovered in two to three years.
- Switch off geysers, chargers and TVs at the plug instead of leaving them on standby.
- Run the washing machine and dishwasher on full loads.
Planning an EV? Use the fuel cost calculator to compare charging cost with petrol, and the unit converter to convert kWh, joules and BTU.
How much is my electric bill? Calculator in three steps
If you are wondering how much your electric bill will be this month, the calculator needs three things: units used, your slab rates and the fixed charge plus duty. Read the units from the meter, copy the rates from your last bill and the answer appears with a slab-wise breakup.
How to calculate electricity bill: calculator vs by hand
By hand you multiply the units in each slab by its rate, add the fixed charge and add duty – easy to get wrong when there are four or five slabs. The calculator does the same sum instantly, and you can change one rate to see what a tariff revision will do to your bill.
Electricity bill calculator from meter reading
Take the current reading (kWh) from your meter display and subtract the previous reading printed on your last bill. For example, 18,642 − 18,392 = 250 units. Enter 250 in the units box and the electricity bill calculator from meter reading gives the same ₹1,228.75 as the worked example above. On smart meters, the kWh register is usually one of the screens that scroll past; ignore kVAh and kW readings, which are for demand billing.
Electricity bill calculator per unit
To find your cost per unit, divide the total bill by the units used. The result panel shows this effective rate; it is always higher than the lowest slab rate because fixed charge and duty are spread over every unit. Use the electricity bill calculator per unit figure to price any new appliance: a 2 kW heater used 2 hours a day adds 120 units a month, or about ₹780 at ₹6.50 a unit.
Electricity bill calculator: UPPCL, Lucknow and Bhopal
For an electricity bill calculator for UPPCL in Lucknow or elsewhere in Uttar Pradesh, enter the domestic slabs and the fixed charge per kW printed on your UPPCL bill; rural and urban connections have different rates. For an electricity bill calculator in Bhopal, use the slabs of the Madhya Pradesh Madhya Kshetra discom shown on your bill – MP bills also show the state subsidy, which you subtract at the end.
Electricity bill calculator in Chennai and Tamil Nadu
For an electricity bill calculator in Chennai, remember that Tamil Nadu bills every two months. Enter the units for the full two-month cycle and double each monthly slab limit, or halve your units, work out one month and double the result. The first block of units is free for domestic consumers under the state scheme, so set the lowest slab rate to zero.
Electricity bill calculator for Jammu and Kashmir
For an electricity bill calculator for Jammu and Kashmir, including homes in and near Srinagar, enter the slab rates from your JPDCL (Jammu) or KPDCL (Kashmir) bill. Many homes in the Kashmir valley still have high winter usage from heaters, so run the calculator for a winter month separately.
Electricity bill calculator for industry
Industrial and large commercial bills add a demand charge per kVA of contract demand, time-of-day rates and sometimes a power factor penalty. As an electricity bill calculator for industry, this page gives a first estimate: put the demand charge (kVA × rate) in the fixed charge box and use the average energy rate from your tariff. For exact industrial bills, use the kVAh units and the time-of-day slabs shown on your bill.
Electricity bill calculator outside India
Switch the currency at the top of the page and the same slab method works elsewhere. In Sri Lanka, the CEB domestic tariff charges each block of units at its own rate plus a fixed monthly charge that depends on your usage band – that is the electricity bill calculation formula Sri Lanka uses, so the electricity bill calculator for Sri Lanka works once you enter those blocks. In Pakistan, LESCO (Lahore) and IESCO (Rawalpindi) bills add taxes and fuel adjustments on top of slab rates; an electricity bill estimator online near Lahore works the same way if you enter those rates. In Egypt, domestic tariffs also use rising consumption tiers.
In Australia there are no slabs on most plans: an electricity bill calculator for QLD or Victoria is just usage (kWh) × the usage rate plus a daily supply charge × days. In the US there is no electric bill calculator by zip code here, but your utility's rate per kWh from any bill is all you need.
Electricity bill calculator in Python and C
A slab-wise electricity bill calculator in Python is a common school exercise. This version matches the worked example:
slabs = [(100, 3.0), (100, 4.5), (200, 6.5), (float('inf'), 8.0)]
def bill(units, fixed=100, duty=0.05):
energy, left = 0, units
for size, rate in slabs:
used = min(left, size)
energy += used * rate
left -= used
return energy + fixed + energy * duty
print(bill(250)) # 1228.75
An electricity bill calculator in C uses the same idea with if–else blocks: charge the first 100 units at the first rate, the next 100 at the second rate and so on, then add the fixed charge and duty. Check your program with 250 units – it should print 1228.75. Those are also good question and answer practice sums for electricity bill calculation.
Electricity bill calculator app or download?
No electricity bill calculator app is needed; this page works on any phone. To get your real slab rates, download your latest bill from your DISCOM's website or app – an online electricity bill download is free and the tariff page lists every slab.
Frequently asked questions
How is electricity bill calculated?
Your DISCOM multiplies the units in each slab by that slab's rate, adds them up, then adds a fixed charge, electricity duty and any fuel cost adjustment. This calculator follows the same steps with slab rates you can edit.
How do I calculate my electricity bill from a meter reading?
Subtract the previous meter reading from the current reading to get units consumed, then enter those units in the calculator with your state's slab rates.
What is 1 unit of electricity?
One unit is one kilowatt-hour (kWh): 1,000 watts used for one hour, for example a 100 W bulb running for 10 hours.
How many units does a 1.5 ton AC consume?
A 1.5 ton AC uses about 1.2–1.5 units per hour. At 8 hours a day that is roughly 300–360 units a month, depending on star rating and thermostat setting.
Why are the default slab rates different from my bill?
Electricity tariffs are set separately for each state and DISCOM and change every year. The defaults are examples only; enter the slabs and rates from your own bill for an accurate estimate.
How much is a yearly electric bill?
The calculator shows the yearly cost at the current usage (monthly bill × 12). Real yearly bills vary because summer AC use is much higher than winter use.
Can I use this electricity bill calculator for a shop or commercial connection?
Yes. Enter the commercial slab rates, fixed or demand charge and duty from your commercial tariff. Industrial bills with kVA demand charges are approximated by adding the demand charge as the fixed charge.
How do I calculate my electricity bill per unit?
Divide the total bill by the units consumed. For 250 units and a ₹1,228.75 bill, the effective cost is about ₹4.92 per unit.
Does this work for a UPPCL or Chennai (TANGEDCO) bill?
Yes, if you enter the slab rates from your own bill. For Tamil Nadu, remember the bill covers two months, so use two months of units and double the monthly slab limits.
How is an electricity bill calculated for industry?
Industrial bills add a demand charge per kVA, time-of-day rates and power factor adjustments. For an estimate, put the demand charge in the fixed charge box and use your average energy rate.
Last updated 2026-09-18