What language and localization settings do, and why they matter

Language and localization settings tell your computer which language to display menus, error messages, and system text in, and which region's formats to use for dates, times, numbers, and currency. When these are set wrong, you might see menus in a language you don't read, dates formatted in an unfamiliar order, or programs that won't run because they're looking for region-specific files.

Changing these settings is straightforward on both Windows and Mac. You don't need to reinstall anything — the language packs are already on your computer, and switching between them takes a few clicks. If you've bought a used computer, inherited one from someone else, or moved to a different country, resetting the language to what you actually use will make your system much easier to navigate.

Key Takeaways

  • Windows stores language settings in Settings > Time & Language > Language & Region, where you can add new languages and set a default one.
  • Mac language settings live in System Settings > General > Language & Region, and changing the primary language takes effect when ready.
  • Your keyboard layout is separate from your display language — you can display menus in English but type in French or Spanish by adding keyboard layouts.
  • Some older programs may not display correctly in languages other than English, so test critical software before committing to a language change.
  • Changing your region format (dates, times, numbers) is independent of language and can be customized separately on both systems.

Changing the display language on Windows 11 and Windows 10

Open Settings by pressing the Windows key and typing "Settings", then click the app that appears. Go to Time & Language in the left sidebar, then click Language & Region. You'll see a section called "Windows display language" with your current language listed.

To add a new language, click the Add a language button. A window will open showing available languages — find the one you want, click it, and then click Next. Windows will ask whether you want to set it as your display language right away or just add it for later use. If you choose to set it now, the menus and system text will switch when ready. If you want to keep English for now and switch later, click "Install" and you can change it anytime by returning to this same screen and selecting the language from the dropdown.

If you don't see your language in the list, scroll down — the list is long. Languages are grouped alphabetically by their English name, so Spanish appears under S, not E. If you're looking for a regional variant (like Brazilian Portuguese versus European Portuguese), click the language name and you'll see options for each region.

Changing the display language on Mac

Click the Apple menu in the top-left corner and select System Settings. Click General in the sidebar, then click Language & Region. The first option, "Preferred languages", shows your current language at the top of the list.

To change it, click the Edit button next to "Preferred languages". A list will appear showing all available languages. Drag the language you want to the top of the list, or click the plus button at the bottom to add a new language and then drag it to the top. Once you've set a new primary language, close the window — the change takes effect when ready, and you'll see system menus switch to your chosen language.

Unlike Windows, Mac doesn't require you to read language packs separately. All major languages are included with the operating system, so the switch is when ready. If you ever want to revert, just return to this screen and drag your original language back to the top.

Setting up keyboard layouts separate from display language

Your keyboard layout — the language you type in — is independent of the language your menus display in. You can have English menus but type in Spanish, French, German, or any other language your keyboard supports. This is useful if you work in multiple languages or live in a bilingual household.

On Windows, go to Settings > Time & Language > Language & Region, scroll down to "Related settings", and click Keyboard. Click Add a keyboard and select the language and layout you want. Once added, you can switch between keyboard layouts using the language switcher in your system tray (usually a small icon in the bottom-right corner of the screen). On Mac, go to System Settings > Keyboard > Input Sources, click the plus button, select your language, choose the layout, and click "Add". You can then switch layouts using the flag icon in the top-right menu bar.

Test your keyboard layout before relying on it for important work. Some layouts, like AZERTY (French) or QWERTZ (German), place common keys in different positions than the standard QWERTY layout, and it takes practice to adjust.

Changing date, time, and number formats for your region

Your region format controls how dates, times, and numbers display — whether a date reads as 12/31/2024 (US) or 31/12/2024 (UK), whether a decimal separator is a period or a comma, and what currency symbol appears. This is separate from your display language, so you can have English menus but UK date formatting, or vice versa.

On Windows, go to Settings > Time & Language > Language & Region. Scroll down to "Regional format" and click the dropdown to select your region. Windows will automatically adjust dates, times, numbers, and currency to match that region's standard. If you want to customize individual formats (for example, use UK dates but US currency), click Related settings > Additional date, time & regional settings, then click Change date, time, or number formats to fine-tune each one.

On Mac, go to System Settings > General > Language & Region. The "Region" dropdown at the bottom controls these formats. Select your region and the system will update when ready. Mac offers less granular control than Windows — you can't easily customize individual formats — but the preset options cover most common needs.

Troubleshooting when language changes don't work

If you've changed your language but some programs still display in the old language, those programs may not support the language you selected, or they may cache the language setting and need to be restarted. Close the program completely and open it again — don't just minimize it. If it still shows the wrong language, the program itself may need to be updated or may not include that language in its installation.

If your system language changed but your keyboard still types in the old layout, you may have added the language without adding the corresponding keyboard layout. Return to your keyboard settings and add the layout separately. On Windows, check the language switcher in your system tray to make sure you're on the right layout — it's straightforward to accidentally switch back without noticing.

If you see garbled text or boxes instead of characters after changing language, your system may not have the font files for that language installed. This is rare on modern Windows and Mac, but if it happens, restart your computer — the system will complete any pending font installations during startup. If the problem persists, check whether the program you're using supports that language by looking at its system requirements or documentation.

When to change language versus when to use a translator

Changing your system language makes sense if you use your computer primarily in one language other than English, or if you live in a region where that language is standard. It affects everything — menus, error messages, file dialogs, and system notifications — so the change is comprehensive and permanent until you switch it back.

If you only occasionally need to read text in another language, or if you work with documents in multiple languages, it's usually better to leave your system language in English and use a browser translator (like Google Translate or the built-in translation in Edge or Chrome) for specific documents or web pages. This keeps your system stable and familiar while still letting you access content in other languages.

Some specialized software — particularly older programs or industry-specific tools — may not work correctly in languages other than English. Before committing to a system-wide language change, test the programs you rely on most. If they don't display correctly or behave strangely, you may need to keep your system in English and use other tools to work with content in your preferred language.

Frequently Asked Questions

Will changing my system language affect my files or documents?

No. Your files, documents, and data remain unchanged. Only the labels on menus, buttons, and system messages switch to the new language. If you have a Word document written in English, it will still be in English after you change your system language to Spanish — only the Word menu bar will display in Spanish.

Can I use multiple languages at the same time?

Yes. You can add multiple languages and keyboard layouts, then switch between them using the language switcher in your system tray (Windows) or menu bar (Mac). This is useful if you work bilingually or live in a multilingual household. You can even set different languages for different user accounts on the same computer.

What happens if I change my language and then want to change it back?

You can change it back anytime using the same settings screen. On Windows, go to Settings > Time & Language > Language & Region and select your original language from the dropdown. On Mac, go to System Settings > General > Language & Region and drag your original language back to the top of the list. The change takes effect when ready.

Do I need to restart my computer after changing the language?

On Mac, no — the change takes effect when ready. On Windows, you may see a prompt asking whether you want to restart, but it's usually optional. If you don't restart, some older programs may still display in the old language until you close and reopen them. Restarting ensures everything switches cleanly.

What if my language isn't in the list?

Windows and Mac both support hundreds of languages, but very small or regional languages may not be included. If your language isn't available, check whether a regional variant is listed instead — for example, if you're looking for a specific dialect, it may be grouped under the main language. If it's truly not available, you may need to use a third-party language pack or consider using a translator tool for specific documents instead of changing your system language.