AC Tonnage Calculator &
Room Size Guide (2026)
Stop guessing. Enter your room dimensions, floor level, and occupancy — get a precise tonnage recommendation in seconds, calibrated for Indian climate conditions.
Rated 4.8 out of 5 by 2,340+ users — India's most trusted AC bill calculator
8+ years practical experience in AC / Plant Installation, Maintenance and Repair. HVAC Expert at S.R Enterprise under the authorized dealership of Hitachi. All data is verified against 2026 BEE Tariff Orders and manufacturer specifications.
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Input Mode
Fill in your room details and click Calculate to see your recommendation.
Pro Tip
Even a perfectly sized AC won't cool efficiently if filters are dirty. See our Maintenance Guide to keep performance at peak.
AC Size Chart: Square Feet to Tons
A quick reference guide based on BEE 2026 standards and Indian climate conditions. Once you know your tonnage, check our Best 1.5 Ton ACs in India list.
* Add 10–15% to tonnage for top-floor rooms with direct roof exposure. Values based on standard 9–10 ft ceiling height.
Why Tonnage Matters: The Cost of
Under-sizing vs. Over-sizing
Getting tonnage wrong is the #1 mistake Indian buyers make — and it costs thousands every year.
Under-sized AC
- ✕Runs continuously at 100% capacity — never reaches set temperature
- ✕Compressor overheats and wears out 2–3x faster
- ✕Electricity bill 20–35% higher than a correctly sized unit
- ✕Room never feels truly cool on peak summer days (45°C+)
- ✕Humidity stays high — feels muggy even when running
Over-sized AC
- ⚠Short-cycles: cools too fast, shuts off, restarts repeatedly
- ⚠Each start-up draws 3–5x normal current — spikes your bill
- ⚠Doesn't run long enough to dehumidify — room feels cold but clammy
- ⚠Higher upfront cost for capacity you'll never use
- ⚠Compressor short-cycling reduces lifespan significantly
The Right-Sized AC: What You Get
30–40%
Lower electricity bill vs. wrong-sized unit
2–3x
Longer compressor lifespan with correct sizing
100%
Dehumidification — truly comfortable air
Now that you know the right size, calculate the exact electricity bill for this AC on our homepage. And remember, even a 2-ton AC won't cool efficiently if not maintained.
How to Measure Your Room for an AC
A 2-minute process that saves you from years of wrong cooling.
Step 1
Measure the Length
Stand at one wall and measure to the opposite wall in feet. Include any alcoves or bay windows in the measurement.
Step 2
Measure the Width
Measure the perpendicular wall. For irregular rooms, measure the longest dimension in each direction.
Step 3
Note Your Floor Level
Top-floor rooms absorb roof heat and need 10–15% more cooling capacity. Middle and lower floors have standard heat loads.
Step 4
Enter Into Calculator
Multiply Length × Width to get square footage, or use our slider. Add occupants and floor type for a precision result.
Got your tonnage? Now find the perfect AC.
Match your tonnage to the right model — and know exactly what it'll cost to run.
Best 1-Ton ACs
Top picks for small rooms up to 120 sq ft — bedrooms, studies, and cabins.
Best 1.5-Ton ACs
India's most popular size — ideal for 120–180 sq ft rooms.
Best 2-Ton ACs
For large rooms, halls, and open-plan spaces above 180 sq ft.
Understand the tech? Now see how it saves you money.
Use our AC Savings Calculator to see your exact payback period and 5-year ROI.
Know Your Tonnage? See Exact Electricity Costs
Find out exactly how many watts your AC uses and what it costs per month — by tonnage and star rating.
Know Your Size? Now Calculate the Bill.
Use our AC Bill Calculator to see exactly how much your new AC will cost per month — and how much you save with a 5-star inverter model.
Go to AC Bill Calculator →