Microsoft has now added a powerful spell checker to PowerPoint online editor. When you are editing text in PowerPoint Online, misspelled words are flagged with a red underline, so you can correct them before you finalize your presentation.
To help you avoid this situation and deliver great, error-free, presentations we added spell check to the PowerPoint Online editor. We previously utilized the browser spell check for PowerPoint Online, but we switched to the high quality Office spell checker.
This feature is already live at Office.com and you can try it on PowerPoint Online. Send them feedback anytime—just click Help Improve Office in the bottom right corner of PowerPoint Online.
Read more at Office blogs.