Back to Conversions

Inches To Millimeters Converter

Perform accurate calculations for Inches To Millimeters Converter.

Formula & Explanation

Formula

Millimeters = Inches × 25.4

Step-by-step explanation

Since one inch is defined as exactly 2.54 centimeters, and there are 10 millimeters in every centimeter, it follows that one inch is equal to 25.4 millimeters. To convert inches to millimeters, simply multiply the inch value by 25.4. For example, 3 inches is 3 × 25.4 = 76.2 mm.

Conversion Table

Inches (in)Millimeters (mm)
125.40
250.80
5127.00
10254.00

FAQ

What is this conversion based on?

The international definition of an inch is exactly 2.54 centimeters, and a centimeter contains 10 millimeters.

Choose the right precision

Millimeters are convenient for small parts. Use sufficient decimals to preserve tolerances when converting from inches.

Guidance

  • 3D printing: keep at least two decimals in mm for critical fits.
  • Fasteners: verify nominal sizes (e.g., 1/4‑20) against metric equivalents rather than raw conversions.
  • CAD exports: ensure your software’s unit settings match project documentation.

Embed This Calculator

Add this calculator to your website or blog using the embed code below:

<div style="max-width: 600px; margin: 0 auto;"> <iframe src="https://mycalculating.com/category/conversions/inches-to-millimeters-converter?embed=true" width="100%" height="600" style="border:1px solid #ccc; border-radius:8px;" loading="lazy" title="Inches To Millimeters Converter Calculator by MyCalculating.com" ></iframe> <p style="text-align:center; font-size:12px; margin-top:4px;"> <a href="https://mycalculating.com/category/conversions/inches-to-millimeters-converter" target="_blank" rel="noopener"> Use full version on <strong>MyCalculating.com</strong> </a> </p> </div>
Open in New Tab

Inches To Millimeters Converter

Perform accurate calculations for Inches To Millimeters Converter.

How to use Inches To Millimeters Converter

Step-by-step guide to using the Inches To Millimeters Converter:

  1. Enter your values. Input the required values in the calculator form
  2. Calculate. The calculator will automatically compute and display your results
  3. Review results. Review the calculated results and any additional information provided

Frequently asked questions

How do I use the Inches To Millimeters Converter?

Simply enter your values in the input fields and the calculator will automatically compute the results. The Inches To Millimeters Converter is designed to be user-friendly and provide instant calculations.

Is the Inches To Millimeters Converter free to use?

Yes, the Inches To Millimeters Converter is completely free to use. No registration or payment is required.

Can I use this calculator on mobile devices?

Yes, the Inches To Millimeters Converter is fully responsive and works perfectly on mobile phones, tablets, and desktop computers.

Are the results from Inches To Millimeters Converter accurate?

Yes, our calculators use standard formulas and are regularly tested for accuracy. However, results should be used for informational purposes and not as a substitute for professional advice.