As you work on a presentation, PowerPoint automatically checks spelling and basic grammar and you can check the spelling of an entire presentation with ease.

Fix spelling as you work

  1. Right-click on a word with a red squiggly line underneath.

  2. Select the correct spelling from the list of suggestions.
    Or you can choose:

    • Ignore All: Ignores the error and removes the red squiggly line.

    • Add to Dictionary: Adds the spelling to the dictionary so that spelling will not show an error in the future.

Check your entire presentation

  1. Select Review > Spelling.

  2. In the Spelling pane, select the correct spelling from the suggestions.

  3. Select Change to fix the error or Change All if it appears more than once in the document.
    Or you can select:

  • Ignore: Ignores the error and removes the red squiggly line.

  • Ignore All: Ignores the error and removes the red squiggly line for all instances in the presentation.

  • Add: Adds the spelling to the dictionary so that spelling will not show an error in the future.

Source: Microsoft