CFM Requirements by Tool
CFM (Cubic Feet per Minute) measures the volume of air moved by your dust collection system. Each tool requires specific CFM for effective dust capture at the source.
Last updated: 2026-02-27
CFM Requirement Calculator
Calculate required CFM (cubic feet per minute) for woodworking tools and design effective dust collection systems. Get tool-specific CFM requirements and system recommendations.
Tool-Specific CFM Duct Sizing Static Pressure System Design
Tool Selection
ft
Total length from collector to tool pcs
90-degree elbows in duct run CFM Requirements
Select a tool and system parameters, then click "Calculate CFM" to see the requirements.
CFM Quick Reference
Table Saw (10 in)350 CFM
Planer (13 in)400 CFM
Jointer (6 in)350 CFM
Band Saw (14 in)350 CFM
Router Table300 CFM
CFM requirements vary by tool size and manufacturer. Always check manufacturer specifications and add a 20% safety margin for system design.
How to Use This Calculator
- 1 Select Tool Choose from 20 common woodworking tools organized by category: Saws, Planers & Jointers, Sanders, Routers & Shapers, and Other.
- 2 Set Port Size Select the dust port diameter on your tool (2.5 in to 6 in). Match duct size to port for optimal airflow.
- 3 Enter Duct Length Measure the total duct run length from dust collector to tool in feet.
- 4 Count Elbows Count 90-degree elbows/bends in your duct run. Each elbow adds static pressure loss.
- 5 Calculate Get required CFM, recommended collector size, duct velocity, and static pressure estimates.
Pro Tip: Size your dust collector for your most demanding tool plus 20% safety margin. Use blast gates to direct airflow to the active tool only, which effectively gives you more CFM at that tool.
| Tool | CFM Required | Port Size | Notes |
|---|---|---|---|
| Table Saw (10 in) | 350 CFM | 4 in | Blade guard + splitter collection |
| Table Saw (12 in) | 450 CFM | 4 in | Higher volume cutting |
| Planer (13 in) | 400 CFM | 4 in | Heavy chip production |
| Planer (15-20 in) | 500-785 CFM | 4-6 in | Industrial volume |
| Jointer (6-8 in) | 350-450 CFM | 4 in | Continuous shavings |
| Band Saw (14-18 in) | 350-500 CFM | 4 in | Fine dust generation |
| Router Table | 300 CFM | 4 in | High-speed fine particles |
| Drum Sander | 400 CFM | 4 in | Very fine dust |
| CNC Router | 500 CFM | 4 in | Continuous operation |
CFM values based on 4000 FPM capture velocity. Add 20% safety factor for system design.
Duct Sizing Impact
Duct diameter significantly affects airflow capacity and velocity. Properly sized ducts maintain transport velocity to prevent dust settling.
| Duct Diameter | CFM Range | Air Velocity | Best For |
|---|---|---|---|
| 2.5 in | 100-200 CFM | 3500-4500 FPM | Small tools, scroll saw |
| 3 in | 200-300 CFM | 3500-4500 FPM | Sanders, small tools |
| 4 in | 300-500 CFM | 3500-4000 FPM | Most stationary tools |
| 5 in | 500-700 CFM | 3500-4000 FPM | Large planers, main trunk |
| 6 in | 700-1000 CFM | 3500-4000 FPM | Main trunk lines |
Maintain 3500-4000 FPM minimum velocity to prevent dust settling in ducts.
SP Loss = (Pipe Length x Friction Factor) + (Elbows x 2.5 ft equiv.) System Design Best Practices
- Size collector for largest tool + 20% margin to handle peak demand
- Use shortest duct runs possible — every foot adds resistance
- Minimize elbows — use 45-degree bends instead of 90-degree when possible
- Install blast gates at each tool — focus airflow where needed
- Use smooth-wall ducting — PVC or metal, not flex hose for long runs
- Seal all connections — air leaks reduce system performance significantly
- Ground ductwork — static buildup in PVC can cause shock or fire
Glossary of Terms
Volume of air moved per minute. Primary measurement for dust collection system capacity. Higher CFM = more air movement and better dust capture.
Air velocity in ductwork. Minimum 3500 FPM needed to transport wood dust. Below this, dust settles and clogs ducts.
Resistance to airflow in the duct system, measured in inches of water gauge (in. w.g.). Higher static pressure requires more powerful collectors.
A sliding valve installed at each tool branch to open/close airflow. Directs all suction to the active tool for maximum CFM delivery.
Air speed at the point of dust generation needed to capture and transport particles. Typically 3500-4500 FPM for wood dust.
Frequently Asked Questions
How much CFM do I need for my dust collector?
Size based on your largest tool requirement plus 20% safety margin. Most hobbyist shops need 400-800 CFM. Small commercial shops: 800-1200 CFM. Use blast gates to run one tool at a time for maximum efficiency.
Can I use flex hose for dust collection?
Flex hose creates 3-5x more friction than smooth-wall ducting. Use it only for short connections (under 6 feet) at tool ports. For main runs, use PVC, metal spiral, or smooth-wall duct for best performance.
How do elbows affect my system?
Each 90-degree elbow adds approximately 2.5 feet of equivalent straight duct resistance. Use 45-degree bends (only 1.5 ft equivalent) when possible. Minimize total elbows to maintain system performance.
What size duct should I use for main lines?
Main trunk lines should be 5-6 inch diameter. Branch lines to individual tools: 4 inch. Never reduce trunk size until after last branch connection. Larger ducts reduce static pressure and allow higher CFM.
Do I need a 1HP or 2HP dust collector?
1HP collectors typically deliver 400-600 CFM at low static pressure. 2HP collectors deliver 800-1200 CFM. For shops with more than 2-3 stationary tools, a 2HP or larger collector is recommended.