HVAC & Airflow

Anemometer Traverse Average Calculator

Average velocity and CFM from grid anemometer readings.

Enter your values

Enter the velocity readings (comma-separated) in FPM.

Enter the opening area in sq ft.

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.

Results
Average velocity
478 FPM
Airflow
1,194 CFM
Reading spread
60 FPM
Points used
6

Quick answer

Average velocity is the simple mean of the traverse readings, multiplied by the free area to get CFM.

CFM = average(V_i) x Area

At a glance

What it doesAverage velocity and CFM from grid anemometer readings.
CategoryHVAC & Airflow
Inputs neededVelocity readings (comma-separated), Opening area
Main outputAverage velocity
FormulaCFM = average(V_i) x Area
CostFree — no sign-up, no download

How to use the Anemometer Traverse Average Calculator

  1. 1Divide the duct or opening into equal-area cells and take a velocity reading in each.
  2. 2Enter all readings comma-separated and the total free area.
  3. 3Read the average velocity and total airflow.

Inputs explained

Velocity readings (comma-separated)(FPM)
Enter the velocity readings (comma-separated) in FPM.
Opening area(sq ft)
Enter the opening area in sq ft.

Worked example

Using the values the calculator loads with:

Inputs

  • Velocity readings (comma-separated)450, 480, 510, 495, 470, 460 FPM
  • Opening area2.5 sq ft

Results

  • Average velocity478 FPM
  • Airflow1,194 CFM
  • Reading spread60 FPM
  • Points used6

Frequently asked questions

Vane or hot-wire anemometer?

Either works — this calculator just averages whatever velocity readings you provide.

Wide spread between readings?

Large variation often indicates turbulence or an obstruction upstream; move the traverse plane if possible.

What do I need to enter into the Anemometer Traverse Average Calculator?

Just 2 values: velocity readings (comma-separated), opening area. 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 Anemometer Traverse Average Calculator work out the answer?

Average velocity is the simple mean of the traverse readings, multiplied by the free area to get CFM. It applies the formula CFM = average(V_i) x Area and shows the working so you can check each step by hand.

Is the Anemometer Traverse Average 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.