Need to convert inches to millimeters? Toolharo’s free Inches to Millimeters converter gives you an exact answer as you type. You can enter decimals or fractions such as 3/4 or 1 3/8, which makes it handy for woodworking, machining, 3D printing, plumbing, and engineering drawings. The tool also shows the result in centimeters and the calculation steps, with a quick reference table for common sizes. Need to go the other way? One click swaps the tool to convert millimeters to inches. It works on any device, with no signup and nothing to install.
| Inches (in) | Millimeters (mm) |
|---|---|
| 1/8 | 3.175 |
| 1/4 | 6.35 |
| 1/2 | 12.7 |
| 3/4 | 19.05 |
| 1 | 25.4 |
| 2 | 50.8 |
| 6 | 152.4 |
| 12 | 304.8 |
How to Use the Inches to Millimeters Converter:
- Enter a value in inches in the left box. You can type a decimal (2.5), a fraction (3/4), or a mixed number (1 3/8).
- The result in millimeters appears instantly in the right box.
- Choose how many decimal places you want from the dropdown.
- Check the extra results: the value in centimeters and the calculation steps.
- Click the swap button (⇆) to convert millimeters to inches instead. The tool also shows the nearest fraction (to 1/64 inch).
- Click Copy result to copy the answer, or use the reference table below for common sizes.
FAQs:
How do I convert inches to millimeters? Multiply the inches by 25.4. For example, 2 inches × 25.4 = 50.8 mm.
How many millimeters are in 1 inch? 1 inch is exactly 25.4 millimeters.
Is 25.4 an exact number? Yes. One inch is defined as exactly 25.4 millimeters, so the conversion is precise.
Can I enter fractions like 1/4 or 3/8? Yes. You can type fractions and mixed numbers, such as 1/4 or 2 3/8, and the tool converts them directly.
How many millimeters is 1/4 inch? 1/4 inch is 6.35 mm.
How do I convert millimeters to inches? Click the swap button, or divide the millimeters by 25.4.
