What Size AC Unit Do I Need? How to Choose the Right HVAC System for Your Home

Key Points

• AC size is measured in tons—1 ton = 12,000 BTUs per hour. Most homes need between 1.5 to 5 tons based on square footage.
• Undersized units run constantly and wear out quickly; oversized units cool too fast without dehumidifying properly.
• The ideal system balances cooling power and humidity control for comfort and efficiency.
• Generic online AC calculators often miss important factors like home layout and number of stories.
• Mint Home’s instant quotes recommend the right tonnage using smart technology—no math or guesswork needed.
• Every quote includes recommended AC size, installation cost, and a system tailored to your home.

If you’re wondering “What size AC unit do I need?”, you are not alone. Choosing the right AC size is the first important step in making sure your home stays comfortable year-round. The best system for your home depends on the home’s layout, location, and overall cooling needs.

Installing an undersized AC unit can leave you sweating through the summer, while an oversized AC unit may cool too quickly without removing enough humidity; leading to higher bills and uncomfortable conditions. The sweet spot is choosing a system with the right AC tonnage per square foot for your specific home.

Let’s break down how to estimate AC size and what to know before you choose a 2-ton, 3-ton, or even 5-ton system.

What Is AC Tonnage, Anyway?

You’ll hear AC units described in “tons”, but not the kind you weigh. A ton of cooling equals 12,000 BTUs (British Thermal Units) per hour. Most residential systems range from 2-ton AC units to 5-ton AC units, depending on the size of the home.

Here’s a rough guide using common AC tonnage per square foot:

Home Size (sqft) Estimated AC Tonnage 600–1,000 1.5 – 2 tons 1,000–1,500 2 – 2.5 tons 1,500–2,000 3 – 3.5 tons 2,000–2,500 4 tons 2,500–3,000 5 tons

Keep in mind: These are rough estimates, so don’t stress about hitting the exact number. We’ll do the heavy lifting when it comes to picking the right size.

Bigger Isn’t Always Better

We get it, it’s tempting to just go for the biggest unit you can afford. But HVAC doesn’t work that way. An oversized AC unit might cool your space too quickly without running long enough to pull moisture out of the air. This can leave you with cold but clammy rooms.

On the other hand, an undersized ac unit will have to run constantly to keep up, driving up your energy bills and wearing itself out too fast.

The goal is to find the “just right” size so your home feels good, and your system lasts.

Why We Don’t Love Other Online AC Size Calculators

Most online ac calculators miss the mark, but ours takes everything into account to give an accurate instant quote.

At Mint Home, we keep it simple and smart. Our free instant quotes take into account your home’s square footage and number of stories to recommend the right AC tonnage. You’ll see that info right in your quote, along with transparent pricing. No upselling, no guessing, just a realistic recommendation that actually makes sense for your home.

We Include the Right Size in Every Quote

With Mint Home, you don’t have to do any math, or second guess what size unit you need. Your quote includes:

• The recommended tonnage for your home
• A real price for installation (no hidden fees)
• A system that fits your space and layout

We use technology to figure out what will work best, and keep the process stress-free from start to finish.

Ready to See What Size You Need?

Whether your home needs a 2-ton, 3.5-ton, or 5-ton system, we’ll show you what fits best. Our instant quotes are backed by data, not guesswork, and take just a minute to complete.

Get an instant quote now, and find out what size AC is best for your home!