Add to phone

Square Millimeters and Square Inches Converter

Spelling: American | British
Use this calculator to convert square millimeters (mm²) to square inches (in²) and square inches to square millimeters. This converter is part of the full area converter tool.


Disclaimer: Whilst every effort has been made in building this calculator, we are not to be held liable for any damages or monetary losses arising out of or in connection with the use of it. This tool is here purely as a service to you, please use it at your own risk. Full disclaimer. Do not use calculations for anything where loss of life, money, property, etc could result from inaccurate calculations.


Converting square inches and square millimeters

In the conversion tables below, figures are rounded to a maximum of 5 decimal places (7 with smaller numbers) to give approximations.

Square Inches to Square Millimeters Conversion Table
Square Inches Square Millimeters
1 square inch 645.16 square millimeters
2 square inches 1290.32 square millimeters
3 square inches 1935.48 square millimeters
4 square inches 2580.64 square millimeters
5 square inches 3225.8 square millimeters
6 square inches 3870.96 square millimeters
7 square inches 4516.12 square millimeters
8 square inches 5161.28 square millimeters
9 square inches 5806.44 square millimeters
10 square inches 6451.6 square millimeters
11 square inches 7096.76 square millimeters
12 square inches 7741.92 square millimeters
13 square inches 8387.08 square millimeters
14 square inches 9032.24 square millimeters
15 square inches 9677.4 square millimeters
16 square inches 10322.56 square millimeters
17 square inches 10967.72 square millimeters
18 square inches 11612.88 square millimeters
19 square inches 12258.04 square millimeters
20 square inches 12903.2 square millimeters
Square Millimeters to Square Inches Conversion Table
Square Millimeters Square Inches
1 square millimeter 0.00155 square inches
2 square millimeters 0.0031 square inches
3 square millimeters 0.00465 square inches
4 square millimeters 0.0062 square inches
5 square millimeters 0.00775 square inches
6 square millimeters 0.0093 square inches
7 square millimeters 0.01085 square inches
8 square millimeters 0.0124 square inches
9 square millimeters 0.01395 square inches
10 square millimeters 0.0155 square inches
11 square millimeters 0.01705 square inches
12 square millimeters 0.0186 square inches
13 square millimeters 0.02015 square inches
14 square millimeters 0.0217 square inches
15 square millimeters 0.02325 square inches
16 square millimeters 0.0248 square inches
17 square millimeters 0.02635 square inches
18 square millimeters 0.0279 square inches
19 square millimeters 0.02945 square inches
20 square millimeters 0.031 square inches

How many square millimeters are there in 1 square inch?

There are 645.16 square millimeters in 1 square inch. To convert from square inches to square millimeters, multiply your figure by 645.16 (or divide by 0.0015500031000062) .

How many square inches are there in 1 square millimeter?

There are 0.0015500031000062 square inches in 1 square millimeter. To convert from square millimeters to square inches, multiply your figure by 0.0015500031000062 (or divide by 645.16) .


What is a square inch?

A square inch is a common unit of measurement within the United States and the United Kingdom. It can be used throughout numerous industries such as construction, graphic design, textiles and painting. Some common abbreviations include sq. in., sq. inches and in/-2. One square inch can approximate the size of many postage stamps. A single square inch is equal to 6.45 square centimeters.

What is a square millimeter?

The square millimeter (or 'millimetre' with British spelling) is a unit defined as a square with each side measuring one millimeter in length. This is abbreviated simply as mm2. This is quite a small area, for an average-sized playing card measures 5,600 square millimeters (56 square centimeters). Square millimeters can be used when designing smartphone screens or determining the total area occupied by an electrical component on a circuit board. Another application can be mapping the scalp before a hair transplantation process takes place.


Other individual area converters

Square Inches and Acres, Square Inches and Square Centimeters, Square Inches and Square Feet, Square Meters and Square Inches, Square Millimeters and Cents, Square Millimeters and Square Centimeters, Square Millimeters and Square Feet, Square Millimeters and Square Inches, Square Millimeters and Square Meters,