Get It Right First Time: Grow Room Fan & Carbon Filter Calculator

The wrong fan or filter is one of the most common — and most expensive — mistakes growers make. Too small and your room overheats, humidity spikes, and odour escapes. Too large and you've wasted money on a fan that cycles your air so fast it never reaches the right temperature. Size matters, and it starts with your room's volume.

Here's why getting both right is critical:

  • Fan too small: Heat and humidity build up, plants stress, and odour isn't controlled — especially under heavy CO₂ or lighting load.
  • Fan too large: You strip out CO₂ before plants can use it, and your environment becomes impossible to dial in.
  • Filter not matched to your fan: A mismatched flange means adapters and air leaks. A filter rated below your fan's output means odour breaks through.

Enter your grow room dimensions below. We calculate the exact m³/hr your room needs using the industry-standard formula — room volume × 60 air changes per hour × 1.3 safety buffer — then match you to every fan and filter that fits, sorted by price.

Step 1 Enter your grow room width, depth and height in cm, m, or ft
Step 2 We calculate the m³/hr your room needs and show matched fans
Step 3 Click any fan to see every matching carbon filter by flange size
Fan & Filter Calculator

Fan type

Units

Room dimensions

Your room is very large — contact us and we'll put together a custom recommendation.

Choose your fan

sorted cheapest first

Matching carbon filters

sorted cheapest first

Matched by flange size and airflow to your selected fan. Everything connects without adaptors.