Unit conversion
Inch to Millimetre Converter
Convert inches to mm instantly. Free inches to mm calculator with formula, examples and FAQs.
Converted value
25.40
1.00 inches = 25.40 mm
Introduction
Need to convert inches to mm? This page gives you an instant calculator, the exact conversion formula, worked examples and answers to common questions. Whether you are studying, travelling, shipping goods or checking specifications, accurate unit conversion saves costly mistakes.
Formula
mm = inches × 25.4
Examples
- •1 inches = 25.4 mm
- •10 inches = 254 mm
- •100 inches = 2540 mm
Related conversions
Support
Frequently asked questions
How do I convert inches to mm?
Multiply your inches value by the conversion factor, or use the formula: mm = inches × 25.4. Our calculator applies this instantly in your browser.
What is the formula for inches to mm?
The standard conversion is: mm = inches × 25.4. Enter any inches value above and the calculator returns the equivalent in mm immediately.
How do I convert mm back to inches?
Reverse the conversion by swapping the units in the calculator, or visit our dedicated mm-to-inches page for the inverse formula and examples.
Is this inches to mm converter accurate?
Yes. Conversions use standard international factors and precise floating-point math. Results are suitable for everyday, engineering and travel use.
When would I need a length conversion like inches to mm?
Common uses include travel planning, shipping labels, school coursework, recipe scaling and reading international product specs. Bookmark this page for quick inches to mm lookups.
Is my data sent to a server?
No. The conversion runs locally in your browser on MerQPrime. Values are never uploaded.
Explore more