CFM per Ton Calculator
Airflow per ton of cooling capacity.
Enter your values
Enter the measured airflow in CFM.
Enter the system capacity in tons.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- CFM per ton
- 383
- Target range
- 350–450 CFM/ton
- Airflow at 400 CFM/ton
- 1,200 CFM
- Difference from target
- -50 CFM
- Verdict
- on target
Quick answer
Most cooling systems are designed for about 400 CFM per ton, lower in humid climates and higher in dry ones.
CFM per ton = airflow / tons
At a glance
| What it does | Airflow per ton of cooling capacity. |
|---|---|
| Category | HVAC & Airflow |
| Inputs needed | Measured airflow, System capacity |
| Main output | CFM per ton |
| Formula | CFM per ton = airflow / tons |
| Cost | Free — no sign-up, no download |
How to use the CFM per Ton Calculator
- 1Measure or read the delivered airflow in CFM.
- 2Enter the nominal capacity in tons (12,000 BTU/h per ton).
- 3Adjust blower speed if the ratio sits outside 350–450.
Inputs explained
- Measured airflow(CFM)
- Enter the measured airflow in CFM.
- System capacity(tons)
- Enter the system capacity in tons.
Worked example
Using the values the calculator loads with:
Inputs
- Measured airflow1150 CFM
- System capacity3 tons
Results
- CFM per ton383
- Target range350–450 CFM/ton
- Airflow at 400 CFM/ton1,200 CFM
- Difference from target-50 CFM
- Verdicton target
Frequently asked questions
Why 400 CFM per ton?
It balances sensible cooling and dehumidification for typical loads.
When should I run lower?
In humid climates 350–375 CFM per ton keeps the coil colder and pulls out more moisture.
What do I need to enter into the CFM per Ton Calculator?
Just 2 values: measured airflow, system capacity. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the CFM per Ton Calculator work out the answer?
Most cooling systems are designed for about 400 CFM per ton, lower in humid climates and higher in dry ones. It applies the formula CFM per ton = airflow / tons and shows the working so you can check each step by hand.
Is the CFM per Ton Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.