# MM to Inches

Convert millimeters to inches with configurable decimal precision

> Canonical page: https://elysiatools.com/en/tools/mm-to-inches

- **Category:** Math & Numbers

- **Keywords:** millimeters, inches, length, conversion, mm, inch

## Overview

The MM to Inches converter allows you to instantly transform millimeter measurements into inches with customizable decimal precision. Perfect for engineering, manufacturing, and crafting, this tool ensures highly accurate length conversions to fit your exact project specifications.

## Inputs

- **Millimeters** (text): e.g. 25.4
- **Decimal Precision** (number)

## When to use

- When converting metric hardware dimensions or technical drawings into imperial units.
- When you need precise control over decimal rounding for manufacturing tolerances.
- When working on international design projects that require switching between metric and imperial measurements.

## How it works

- Enter the length value in millimeters into the input field.
- Specify your desired decimal precision to control the rounding of the output.
- Generate a structured JSON object containing the precise conversion in inches.

## Use cases

- Converting metric bolt and screw sizes to imperial equivalents for mechanical assembly.
- Translating architectural blueprints from millimeters to inches for construction planning.
- Adjusting 3D printing model dimensions from metric STL files to imperial slicer settings.

## Frequently asked questions

### How many millimeters are in an inch?

There are exactly 25.4 millimeters in one inch.

### Can I control the rounding of the converted value?

Yes, you can set the decimal precision from 0 up to 10 decimal places.

### What is the default decimal precision?

The tool defaults to 4 decimal places if no precision is specified.

### Does this tool support negative millimeter values?

Yes, it converts negative values, which is useful for relative offsets or tolerances.

### What format is the output returned in?

The output is returned as a structured JSON object containing both the input millimeters and the converted inches.

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