
Knowing the right tonnage for an AC unit can make or break your HVAC system’s ability to cool your home. Keep reading to learn more about AC tonnage.
Your AC tonnage per square foot depends on your home's size, with most homes needing 1 ton for every 400 to 600 square feet of space.
Expect to pay $3,906 to $8,020 for professional AC replacement, with average costs around $5,900 depending on your unit size and installation needs.
You can calculate your AC tonnage by multiplying your square footage by 25, then dividing by 12,000 to find the right cooling capacity.
Hiring a local heating and air conditioning professional provides accurate tonnage calculations and proper installation, accounting for your ductwork, insulation, and climate conditions.
Air conditioner tonnage is a measure of how large an air conditioner is and, therefore, how much cooling capacity it has. Tonnage refers to how many BTUs of heat the AC can remove each hour—one ton of cooling equals 12,000 BTUs of heat removed per hour. If you’re wondering, “What tonnage AC do I need?” we can help. Calculating tonnage will help you choose the unit that has a sufficient cooling capacity without being too large or too small.

When it’s time to upgrade your AC, you can get a good idea of the AC tonnage you need by estimating based on the size of your home. You’ll also need to consider other factors like insulation, type of AC unit, amount of sun exposure, usage of heat-generating appliances, the region you live in, and home features that can modify the temperature, like a fireplace, among others.
Using the square footage of your house, refer to the chart below to get an estimate of AC tonnage.
| Square Feet | AC Size |
|---|---|
| 600 | 1–2 tons |
| 1,000 | 2 tons |
| 1,500 | 3–4 tons |
| 2,000 | 4 tons |
| 2,500 | 5–6 tons |
| 3,000 | 6–7 tons |
To calculate AC tonnage, you’ll need to know how many square feet your home is and then apply the following formula:
AC Tonnage = (Square feet x 25) / 12,000
Before you can determine the AC tonnage you need and choose a central air conditioner, you should measure the square footage of your home. To do this, measure the length and width of each room and multiply them together. You may have to break the room into smaller sections or regular shapes for large or irregularly shaped rooms.
Once you have the measurements of each room, add them together to determine the total square footage.
A local HVAC pro can come to your home and estimate the tonnage of your new AC unit. Using the square footage as a starting point, they’ll also take other factors into consideration, including the quality and condition of your ductwork and insulation, the amount of direct sun exposure your home gets, the quality of the number of windows and doors, the material your home is made of, and the local climate. Using all of these inputs, they’ll be able to give you an accurate estimate so you can purchase the right size air conditioning unit.
Great company! Price was competitive, technician showed up on time and completed the job (exterior electric Radon fan replacement) quickly. Would hire them again.
As usual with ECO, tech Jordan was outstanding, very professional, very knowledgeable, and very thorough with repairs made to tankless water heaters. Very highly recommend ECO!!!
Raven and crew does absolutely fantastic job. They are very professional if any concerns were to occur with any of her work she always took responsibility and finished out with a great job. I have worked with her business for a year and have always been satisfied. Very trusted business and...
I would recommend this company to anyone! He showed up on time, was friendly, completed a very difficult repair on our dryer vent cover, was responsive, and pricing was extremely fair and competitive. I would have him back to do any of our repairs or cleanings without hesitation!
Ace Fireplace Services' chimney sweep service is truly exceptional. They used advanced technology to ensure a thorough cleaning process, and my chimney has never looked better. I highly recommend their services.
The technician was very professional and friendly. He answered all my questions and was very thorough. He left the fireplace area very clean . He inspected from the roof and advised me as to other work that might need to be done. There was no pressure there. I was very satisfied with the...
Excellent experience with hiring Tether House to Mount our 77’ Samsung TV in our bedroom. Fast, friendly, and knowledgeable. Highly recommend.
On time, clean and finished fast. Windows seem sturdy and the finish is good. Caulking was done with no smudges. Would recommend.
Great job...edging and pre clean up went well with a great job with seal coat. Friendly, efficient and professional.
Good workers and they do a good job.
From average costs to expert advice, get all the answers you need to get your job done.

Knowing the right tonnage for an AC unit can make or break your HVAC system’s ability to cool your home. Keep reading to learn more about AC tonnage.

What is a Manual J load calculation? It’s used to find out how many heating units your house needs. Discover how to use this complicated formula.

How much pea gravel do I need? This calculator will help you determine quantity and cost for accurate budgeting for your project.

How many bricks do you need for a brick home project? Our brick calculator and guide will help you determine the correct number so you don’t over- or underbuy.

It’s snowing up a storm outside when you start to wonder: How much snow can my roof hold? Use our snow load calculator to determine your roof’s limits.

You’ll need to estimate demolition waste to rent dumpsters or trucks for hauling it away. Learn how to calculate demolition debris with this guide.