Quote Cart
mm ↔ Inches Converter
Convert between millimetres (mm) and inches instantly. Essential for comparing pipe sizes, duct dimensions, and component measurements between metric and imperial specifications.
mm to Inches Conversion
1 inch = 25.4 mm. To convert mm to inches, divide by 25.4. To convert inches to mm, multiply by 25.4. For example, 22 mm = 0.866 inches.
HVAC pipe sizes often use both systems: copper tube is measured in mm (15, 22, 28 mm) while refrigerant pipes use inches (1/4, 3/8, 1/2 inch).
Frequently Asked Questions
How many inches is 22 mm?
22 mm = 0.866 inches. Divide mm by 25.4 to get inches.
How many mm is 1/2 inch?
1/2 inch = 12.7 mm. Multiply inches by 25.4 to get mm.
Why do refrigerant pipes use inches?
Refrigerant pipe sizes (1/4, 3/8, 1/2, 5/8 inch) follow US standards from the air conditioning industry. Copper plumbing tube uses metric sizes (15, 22, 28 mm) in the UK.
mm ↔ Inches Converter
Related Quick Converters Tools
Need Professional Help?
Post a request and get competing quotes from rated HVAC engineers nationwide.