Present with Real-Time, Automatic Captions or Subtitles in PowerPoint

PowerPoint for Microsoft 365 can transcribe your words as you present and display them on-screen as captions in the same language you are speaking, or as subtitles translated to another language. This can help accommodate individuals in the audience who may be deaf or hard of hearing, or more familiar with another language, respectively.

There are also position, size, color, and other appearance options for the captions and subtitles to accommodate different environments and audience needs.

Set up captions and subtitles

You can choose which language you want to speak while presenting, and which language the caption/subtitle text should be shown in (i.e., if you want it to be translated). You can also select whether subtitles appear at the top or bottom of the screen.

Simplified Ribbon:

On the Slide Show ribbon tab, select the drop-down arrow next to Always Use Subtitles to open the menu of options.

Classic Ribbon:

On the Slide Show ribbon tab, select Use Subtitles. Then click Subtitle Settings to open the menu of options.

Choose Spoken Language to see the voice languages that PowerPoint can recognize, and select the one you want. This is the language that you will be speaking while presenting. (By default, this will be set to the language corresponding to locale of your web-browser.)

Choose Subtitle Language to see which languages PowerPoint can display on-screen as captions or subtitles, and select the one you want. This is the language of the text that will be shown to your audience. (By default, this will be the same language as your Spoken Language, but it can be a different language, meaning that translation will occur.)

Set the desired position of the captions or subtitles: they can appear overlaid at the top or bottom margin of the slide. The default setting is Bottom (Overlaid).

Turn the feature on or off while presenting

To have subtitles always start up when a Slide Show is presented, select Slide Show > Always Use Subtitles.

If you’re in the middle of giving a presentation and want to turn the feature on or off, click the Use Subtitles button in Slide Show, on the toolbar below the main slide:

On/Off keyboard shortcut: J

Windows: Requires Windows 10 and later, with PowerPoint for Microsoft 365 version 16.0.11601.20178 or higher on Current Channel. The feature isn’t supported if you’re using an earlier version of Windows

Set up captions and subtitles (Windows)

You can choose which language you want to speak while presenting, and which language the caption/subtitle text should be shown in (i.e. if you want it to be translated). You can select the specific microphone you want to be used (if there is more than one microphone connected to your device), the position where the subtitles appear on the screen (bottom or top, and overlaid or separate from slide), and other display options.

On the Slide Show ribbon tab, select Subtitle Settings. Or, you can adjust the settings without leaving your presentation through the context menu, Slide Show or Presenter View menus > Subtitle Settings > More Settings.

Use Spoken Language to see the voice languages that PowerPoint can recognize, and select the one you want. This is the language that you will be speaking while presenting. (By default, this will be set to the language corresponding to your Office editing language.)

Use Subtitle Language to see which languages PowerPoint can display on-screen as captions or subtitles, and select the one you want. This is the language of the text that will be shown to your audience. By default, this will be the same language as your Spoken Language, but it can be a different language, meaning that translation will occur.

In the Subtitle Settings menu, set the desired position of the captions or subtitles. They can appear over the top or bottom margin of the slide (overlaid), or they can appear above the top or below the bottom of the slide (docked). The default setting is Below Slide.

More appearance settings are available by clicking Subtitle Settings > More Settings (Windows).

You can change the color, size, transparency, and font style of the subtitles. You can change the background to improve contrast and make text easier to read.

Turn the feature on or off while presenting (Windows)

If you’re in the middle of giving a presentation and want to turn the feature on or off, click the Toggle Subtitles button from Slide Show View or Presenter View, on the toolbar below the main slide:

You can also toggle subtitles from the right-click menu, or with the shortcut key J.

To have subtitles always start up when a Slide Show presentation starts, from the ribbon you can navigate to Slide Show > Always Use Subtitles to turn this feature on for all presentations. (By default, it’s off.) Then, in Slide Show and Presenter View, a live transcription of your words will appear on-screen.

Source Microsoft Support: Present with real-time, automatic captions or subtitles in PowerPoint