Electricity Bill Calculator
An electricity bill has three parts: units at slab rates, a fixed monthly charge, and taxes. Slabs differ by discom and state — the first 100 units might cost ₹4.90 under one tariff and ₹3.50 under another — so hardcoding one state's rate table would be wrong for everyone else. Take the rates printed on YOUR bill and this page returns the bill-ready total, with each tier broken out.
Enter values
Results
- Estimated bill
- ₹1,400.00
- Tier 1 charge
- ₹490.00
- Tier 2 charge
- ₹800.00
- Fixed charge
- ₹110.00
How is the Electricity Bill calculated?
Open your latest bill and copy three things: the rate for the first block of units, how many units that block covers, and the rate for units beyond it. Add the fixed monthly charge shown on the bill. Enter your consumption for the period in units — the same kWh the meter bills. The calculator charges the first slab at its rate, everything above the limit at the second rate, adds the fixed charge, and returns the estimated bill with every component listed separately.
Formula
Bill = min(units, limit) × rate₁ + max(0, units − limit) × rate₂ + fixed charge where: units = kWh consumed in the billing period rate₁ = ₹ per unit within the first slab limit = how many units the first slab covers rate₂ = ₹ per unit beyond the first slab fixed charge = flat monthly rental for the connection
Example
Units: 200 · Tier 1: ₹4.90/unit for the first 100 · Tier 2: ₹8.00/unit beyond that · Fixed charge: ₹110 Tier 1 = 100 × ₹4.90 = ₹490 · Tier 2 = 100 × ₹8.00 = ₹800 · Fixed = ₹110 Estimated bill = ₹1,400 A flat ₹6 for all 200 units would be only ₹1,200 — slabs are exactly why a high-use summer month costs proportionally more per unit, not less.
Things to remember
Re-check the slab split on your bill once a quarter: discoms revise tariffs, and the fixed charge lands whether you use the power or not. The levers on a high bill are structural — tariff plan, efficient appliances, solar net metering — not small habits. Taxes sit on top, so the printed bill runs a few percent higher.
Frequently Asked Questions
How do I find my slab rates on the electricity bill?
Look for the tariff or units block near the front: it lists the slab boundaries and the rate per unit for each, plus the fixed-charge line. Copy those two rates and the boundary into this calculator and the estimate should land within a few rupees of the printed amount.
Why is my bill higher than units times the first rate?
Because the second slab's higher rate, the fixed charge and taxes all stack on top of the first slab's units. At 200 units with ₹4.90 and ₹8.00 slabs plus ₹110 fixed, the arithmetic alone is ₹1,400 — against ₹980 if every unit were charged at the first slab rate.
Do commercial connections use the same slab structure?
Often not — many commercial tariffs are single-rate plus a much higher fixed demand charge. This calculator handles that too: set both rates equal, or set the tier-1 limit above your full consumption, and the second slab simply never applies.
How can I reduce my monthly electricity bill?
Check the fixed charge first — a higher connected load raises it every month whether you use it or not. Then look at the big two: an efficient air conditioner and LED lighting usually beat every small habit combined. Where time-of-day pricing exists, shifting usage outside peak slabs cuts the per-unit rate itself.
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