Windows: select or add a layout
- Click the taskbar input-language icon and choose the required keyboard layout. Windows+Space cycles through installed layouts.
- To add one, open Settings → Time & language → Language & region, open the language’s options, then use Add a keyboard.
- Choose the exact variant. Changing the keyboard layout changes input, not necessarily the Windows display language.
macOS: select or add an input source
- Choose the source from the Input menu in the menu bar.
- If the menu is hidden or the source is missing, open System Settings → Keyboard → Text Input → Edit. Add the desired source and enable Show Input menu in menu bar.
- Use Keyboard Viewer to inspect the selected layout and how Shift or Option changes its characters.
Compare the right things
In the layout test, select the same expected layout and try plain letters and punctuation. That tool selection compares characters; it does not change your computer’s input source.
Release modifiers and check Caps Lock before comparing. A dead key or input method can compose a character over multiple presses. Test the finished text in your editor too.
Recover text already typed in the wrong layout
Keep the original text. Convert only the wrong-layout segment, choosing the source layout that produced it and the destination you intended. Review punctuation and mixed-language text before copying.
Changing the active input source corrects future typing; it does not rewrite an existing document.