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Keycap Sizing Guide

Keycaps are the components of a keyboard that are responsible for typing letters, numbers, and symbols. Keycap sizing is a crucial aspect that determines how well the keycap fits on the switch stem. Measuring the keycap size is important to ensure compatibility with the keyboard and to avoid any misfits that could hamper typing accuracy and speed. In this guide, we will explore the different keycap sizes and how to measure them accurately.

Keycap Sizing: Measuring Units

Keycap size is measured in units or “u,” which represents the width of the keycap in relation to the standard 1-unit size. The standard 1-unit size keycap measures 19.05mm (0.75 inches) in width. Different keycap sizes are available in the market, and their measurements are indicated in terms of “u” or fractions of the standard 1-unit size.

Common Keycap Sizes

Here are some of the common keycap sizes and their measurements:

2.25 U keycaps
6.25 U spacebars
1.5 U keycaps
1.75 U keycaps
Other common keycap sizes are also available, and they have their specific uses, such as ergonomic or layout optimization. To ensure compatibility with your keyboard, you should carefully measure the keycap size and compare it with the manufacturer’s specifications.

Keycap Profile: Understanding Different Shapes and Heights

The keycap profile is an important factor in determining the overall feel and aesthetic of a keyboard. Keycap profiles refer to the overall shape of the keycap, and they can be flat, rounded, or have many different shapes.

Different keyboard manufacturers use different keycap profiles, and there are certain styles in which each row of keys has a different height to allow for a concave or sloped shape over the entire keycap. Understanding the different keycap profiles and shapes can help you choose the right keycap set for your keyboard.

Removing and Installing Keycaps: The Friction-Fit Mechanism

Keycaps attach to the switch stem using a simple friction-fit mechanism. To remove them, you need a keycap puller, which is a wire loop that fits under each side of the keycap. Gently pulling the keycap upward will disengage it from the switch stem.

When installing keycaps, you need to ensure that they are aligned correctly on the switch stem. Pressing the keycap firmly down onto the switch stem until you hear a click indicates that it is correctly attached.

I. Keycap Sizing Guide: A Quick Overview

Before diving into a detailed discussion of keycap sizes, let’s first have a quick overview of the different sections of a keyboard:

Alphanumeric section: This section includes letters, numbers, and special characters. It is located in the middle of the keyboard.
Function section: This section is located above the alphanumeric section and includes function keys and media keys.
Navigation section: This section is located on the right side of the keyboard and includes arrow keys, home, end, page up, and page down keys.
Numeric section: This section is located on the right side of the keyboard and includes a numeric keypad.
Now that we have an understanding of the different sections of a keyboard, let’s dive into the different keycap sizes.

II. Different Keycap Sizes

Keycap size is measured in units or “u.” A standard keycap size is 1u, which is the size of most keys on a keyboard. However, some keys, such as the spacebar and enter key, come in different sizes.

Here are the most common keycap sizes and their uses:

1u keycaps: These keycaps are the standard size and are used for letters, numbers, and most other keys on a keyboard.
1.25u keycaps: These keycaps are slightly smaller than the standard size and are used for keys such as shift, tab, and caps lock.
1.5u keycaps: These keycaps are larger than the standard size and are used for keys such as control, alt, and function.
1.75u keycaps: These keycaps are larger than the 1.5u keycaps and are used for keys such as enter and right shift.
2u keycaps: These keycaps are larger than the standard size and are used for keys such as backspace and delete.
2.25u keycaps: These keycaps are larger than the 2u keycaps and are used for keys such as the left shift, the right shift, and the enter key on a standard layout keyboard.
2.75u keycaps: These keycaps are larger than the 2.25u keycaps and are used for keys such as the left shift on an ISO layout keyboard.
6.25u spacebar: This is the standard size for the spacebar on most keyboards.
7u spacebar: This size is used on some larger keyboards.
It’s important to note that some keycaps come in different sizes across varied layouts for reasons ranging from ergonomics to optimization of key placement.

III. How to Measure Keycap Sizes Accurately

To measure keycap sizes accurately, you’ll need a keycap puller and a ruler or measuring tape. Here are the steps to follow:

Use the keycap puller to remove the keycap you want to measure.
Measure the distance between the centers of the two keycap mounting stems. This will give you the size of the keycap.
Record the size of the keycap in units or u.
It’s important to measure keycaps accurately to ensure that you purchase the correct size keycaps for your keyboard.