ANSI vs. ISO Keyboards - Which layout is right for you?

ANSI stands for the American National Standards Institute, and it defines the layout most commonly used in the United States, Canada, and the Asia-Pacific region.

You’ll recognize the ANSI layout by the wide, horizontal Enter key and long left Shift key. It typically includes 104 keys on a full-size layout.

Key features of an ANSI keyboard

• It’s the default in North America
• It’s widely supported by mechanical keyboard manufacturers
• It’s often the layout used for custom keycap sets and PCBs (Printed Circuit Boards)

ISO refers to the International Organization for Standardization, and this layout is standard across the UK and the rest of Europe.

You’ll spot the ISO layout by the tall, L-shaped Enter key and shorter left Shift key, which makes room for an additional key used for language-specific characters.

Key features of an ISO keyboard

• 105 keys on a full-sized keyboard (one more than ANSI)
• Designed for multilingual compatibility
• Standard in all European countries for regional typing needs

Let’s compare the physical differences side by side.

Note: key counts (104 vs. 105) refer to typical full‑sized keyboards for Windows. Counts can vary by platform and model, but in general, ANSI has fewer keys.

Other keys, such as the left and right Alt key, the Control keys, the Delete key, Caps lock, navigation keys, modifier keys, and the home row (the most frequently used letters) are similar between both keyboard layouts.

ISO does also feature the Alt Gr key, unlike ANSI. This key (only for Windows) provides access to tertiary characters like accents and special punctuation.

If you’re unsure which layout you’re using, look at your Enter key:

• A wide rectangular Enter key = ANSI.
• A tall Enter key shaped like an upside down L = ISO.

You can also check the Shift key on the left of your keyboard:

• ANSI uses a long left Shift key.
• ISO uses a shorter left Shift key with an extra key to its right.

That extra key is often used for symbol keys like \, |, or regional characters depending on your country.

ANSI layout

• United States
• Canada
• Some parts of Asia
• Australia and New Zealand

ISO layout

• Europe

Much of Latin America (including Mexico) uses the Latin American Spanish layout (ISO keyboard layout family).

Beyond ANSI and ISO: PTB and JIS layouts

While ANSI and ISO layouts are the most discussed, Logitech® also supports two other layouts:

• PTB (Brazil): Similar to ISO (tall Enter) with one additional key next to each Shift for Portuguese-language characters.
• JIS (Japan): Backspace split into two keys, tall Enter, long left Shift and one extra near right Shift, and three dedicated bottom‑row keys for Kana.

The history and evolution of keyboard layouts

The story of ANSI, ISO, PTB, and JIS starts with the typewriter. The QWERTY layout was created in 1868 to prevent mechanical jams. When computers emerged, ANSI and ISO formalized regional variations.

• ANSI (1980s): The American National Standards Institute standardized the U.S. layout with long Shift keys and rectangular Enter.
• ISO (1980s): The International Organization for Standardization defined European layouts, adding flexibility for extra language characters.

Today, more than 30 country-specific layouts exist, from German QWERTZ to French AZERTY, but almost all are rooted in ANSI, ISO, PTB, or JIS.

Neither layout is objectively better. The right choice depends on where you live and how you type.

Advantages of ANSI

• Widely available in the U.S. market.
• Easier to find replacement keycaps and mechanical keyboards.
• Larger left Shift key is comfortable for many users.

Advantages of ISO

• Extra key supports special characters needed in European languages.
• L-shaped Enter key can feel more natural to some typists.
• Standard in the UK and many European countries, ensuring consistency across devices.

Generally, no. ANSI and ISO keycaps differ in size and shape, especially for the Enter, Shift, and surrounding keys. While some keys are interchangeable, a full set will not fit properly across layouts.

Tip: If you're customizing your mechanical keyboard, make sure your keycap set matches your layout. Or go for a “universal” set that supports both ANSI and ISO configurations.

Programmers in the U.S. often favor ANSI because it places characters like the backslash key, { }, and [ ] in intuitive positions. They're key for writing code.

European programmers who are used to ISO layouts don’t typically notice a drop in performance; it’s all about what you’re used to. But if you're switching layouts mid-career, expect a short adjustment period.

For most gamers, choosing ANSI or ISO comes down to comfort and familiarity.

ANSI layouts tend to be favored by players in the U.S. because:

• The larger Shift key makes it less likely to miss a press during fast gameplay.
• Keycap and switch availability is wider, making it easier to customize mechanical keyboards for gaming setups.

ISO layouts hold their own advantages, especially in Europe:

• The extra key near Shift can be mapped for in-game actions or macros.
• The tall Enter key can feel easier to hit without looking down, depending on grip and play style.

ANSI or ISO won’t make you faster or more accurate. But a responsive, ergonomic keyboard can give you a real edge in comfort during gaming sessions.

Not directly. Typing speed and comfort are influenced more by ergonomics, key spacing, and keyboard quality than by the layout itself. Familiarity with different key types such as laptop keys (scissors) or deep keys (plungers) also affects typing speed.

That said, switching between layouts can temporarily slow you down, especially if you're using muscle memory built for ANSI and switch to ISO (or vice versa).

At Logitech, all our keyboard designs feature optimized pitch (key spacing), responsive switches, and concave keycaps for a smoother typing experience.

• ANSI is standard in North America, ISO in the UK and Europe.
• ISO includes one extra key and a different Enter key shape.
• Keycap sets are not interchangeable between layouts.
• Neither ANSI nor ISO is better; it depends on your region and preferences.

Keyboard layouts may seem like a minor detail, until they’re not. If you’ve ever hit the wrong key mid-sentence or struggled to find a symbol, you know how frustrating it can be.

The good news? Whether you prefer ANSI or ISO, Logitech makes keyboards that meet your regional needs and individual preferences.

For more information about keyboards and layouts, check out our FAQ for media keyboards.