Does floor level affect AC tonnage?

Yes. Top floor rooms receive more heat through the roof and may need 10-15% more cooling capacity. Ground floor rooms are cooler and may need slightly less.

What is a 5-star vs 3-star AC?

5-star rated ACs consume 25-30% less electricity than 3-star models for the same cooling. The upfront cost is higher but it saves ₹3,000-6,000/year on electricity depending on usage. Split inverter ACs are the most efficient.

AC Tonnage Calculator — Right Air Conditioner Size

Room Length (ft)

Room Width (ft)

Ceiling Height

Floor Level

City / Climate Zone

Sunlight / Window Exposure

Number of People (usual occupants)

Kitchen Heat Load

ℹ️ How it's calculated

Base BTU = Room area (sq ft) × 60 BTU/sq ft — adjusted for Indian climate conditions
Adjustments applied for ceiling height, floor level, climate zone, sunlight, occupants, kitchen
1 Ton = 12,000 BTU/hour
Final result rounded to nearest available AC size (0.75, 1, 1.2, 1.5, 2, 2.5, 3 ton)

📊 Quick Reference

Up to 120 sq ft0.75 ton

120–180 sq ft1 ton

180–240 sq ft1.2–1.5 ton

240–320 sq ft1.5–2 ton

320–480 sq ft2–2.5 ton

480–600 sq ft3 ton

🔗 Related Tools

❓ Frequently Asked Questions

How is AC tonnage calculated?

The basic rule is 60 BTU per sq ft for Indian conditions. A 150 sq ft room needs about 1 ton, a 250 sq ft room needs 1.5 tons, and 350 sq ft needs 2 tons. Adjustments are made for floor level, climate, sunlight, and occupants.

What happens if AC tonnage is too high or too low?

Too high: short-cycles, causing humidity problems and higher bills. Too low: runs continuously without reaching target temperature, reducing efficiency and lifespan.

1 ton AC covers how many square feet in India?

In Indian conditions, 1 ton is typically sufficient for 100–150 sq ft. In very hot cities like Delhi, consider 1 ton per 100–120 sq ft.

Should I buy 1 ton or 1.5 ton AC?

Use this calculator. Roughly: up to 150 sq ft = 1 ton, 150–250 sq ft = 1.5 ton, 250–400 sq ft = 2 ton. When in doubt, go slightly higher — undersized AC costs more to run.

What is 5-star vs 3-star AC?

5-star ACs consume 25–30% less electricity than 3-star models. The upfront cost is higher but saves ₹3,000–6,000/year on electricity. Inverter split ACs are the most efficient choice.