If you are building an automated kiosk presentation for a trade show, or creating a self-running digital training module for your company, you likely have a pre-recorded voiceover file (like an MP3) that you want to play while the slides are displayed. However, trying to manually set the slide transition timers (e.g., telling Slide 1 to advance after exactly 14.5 seconds, and Slide 2 to advance after 8.2 seconds) to perfectly match the pacing of the audio track is a maddening, mathematically frustrating process.
Instead of doing the math manually, you can use PowerPoint’s “Rehearse Timings” feature to physically listen to the audio track and click through the slides live, permanently recording those precise click-timestamps into the presentation file.
Step 1: Insert the Master Audio Track
First, we need to embed the voiceover file so it plays continuously across the entire presentation, rather than stopping when the slide changes.
- Go to Slide 1.
- Click the Insert tab on the top ribbon, go to the far right, click Audio, and select Audio on My PC. Select your MP3 file.
- A small speaker icon will appear on the slide. Click it so it is highlighted.
- Look at the top ribbon for the new Playback tab and click it.
- Check the box labeled Play Across Slides.
- Check the box labeled Hide During Show (so the ugly speaker icon vanishes when presenting).
- Change the “Start” dropdown menu to Automatically.
Step 2: Open the Rehearsal Studio
Now we are going to record the automation.
- Click on the Slide Show tab on the main ribbon.
- Ensure the checkboxes for Play Narrations and Use Timings are checked.
- Click the Rehearse Timings button.
Step 3: Record the Timestamps Live
The moment you click “Rehearse Timings,” your presentation will launch in full screen, and your embedded audio track will immediately begin playing from the beginning.
- A small “Recording” toolbar will appear in the top left corner of the screen, showing a running stopwatch.
- Listen closely to the audio track.
- The exact moment the voiceover begins talking about a topic that belongs on Slide 2, click your mouse (or press the right arrow key on your keyboard).
- The slide will instantly advance to Slide 2, but the audio will continue playing seamlessly.
- Continue listening, and click your mouse to advance the slides exactly when the audio dictates it.
- When you reach the final slide and the audio ends, press the Esc key on your keyboard.
Step 4: Save the Automation
When you press Esc, a dialogue box will pop up saying: “The total time for your slide show was [XX:XX]. Do you want to save the new slide timings?”
Click Yes.
You are done. If you press F5 to launch the presentation right now, you can take your hands completely off the keyboard. The audio will begin playing, and PowerPoint will automatically advance every single slide at the exact millisecond you clicked your mouse during the rehearsal process. You can now safely export the file as an MP4 video or distribute it as an automated kiosk file.