How to Add an AI Voiceover to a TikTok Video

A voiceover does two things for a short video: it holds attention through the first few seconds, and it lets you cut the picture freely because the story is carried by sound. You do not need a microphone to have one. Here is the whole process on an iPhone.

What you need

• A text to speech app. This guide uses Voice Labs, which is free to download and includes 2 free generations.
• A video editing app. CapCut and iMovie are common choices; any editor that can import an audio file works.
• Your clips.

Step 1: Write a script to length

Short-form scripts are counted in seconds. At a natural pace an AI voice speaks about two and a half words a second.

Video	Words
7 to 10 seconds	18 to 25
15 seconds	35 to 40
30 seconds	70 to 80
60 seconds	140 to 160

Put the hook first. The opening sentence should be the question, the claim or the result, never the greeting.

Weak: “Hey everyone, today I’m going to show you something I found.”

Strong: “This two-pound gadget fixed the most annoying thing about my kitchen.”

Then keep every sentence short. One idea each. Full stops are where you will cut.

Step 2: Generate the voiceover

1. Open Voice Labs and paste your script.
2. Open the voice library and choose a language.
3. Tap Preview on a few voices and pick one.
4. Tap Generate.

The audio is ready in a few seconds.

Step 3: Check the read

While the clip plays, the line being spoken is highlighted and each word lights up. Listen for three things:

• Pace. Too slow for the format? Raise Speed slightly, or switch to the Expressive preset.
• Pauses. A pause in the wrong place is a punctuation problem. Move or remove the comma.
• Pronunciation. If a name is wrong, spell it the way it sounds.

Fix the script and generate again. It is normal to do this two or three times.

Step 4: Save or share the audio

Save the audio to your iPhone, or use the share option to send it directly to your editing app. The clip also stays in the app’s History if you need it again.

Step 5: Add it to your clips

In your video editor:

1. Start a project with your clips.
2. Import the voiceover as an audio track. Look for an option such as “add audio”, “sounds” or “import from Files”.
3. Play it through and trim each clip so the shot changes on a sentence break.
4. Lower or remove the original clip sound so it does not fight the voice.
5. If you add music, keep it quiet enough that every word is clear.

Always fit the picture to the voice. Trimming half a second from a clip is easy. Removing half a second from a sentence is not.

Step 6: Captions, export, post

Add captions that match the voiceover. Many viewers watch without sound, and captions also help people follow fast speech. Export the finished video and upload it to TikTok like any other.

Five things that make AI voiceovers better

1. Use one voice per series. People recognise an account by ear.
2. Start mid-thought. Drop the introduction entirely.
3. Write numbers as words if pronunciation matters.
4. End with an action. Tell viewers what to do next.
5. Reuse the audio. The same file works for YouTube Shorts and Instagram Reels.

If something goes wrong

• The voice sounds flat. Try the Expressive preset, or shorten your sentences.
• It runs too long. Cut a sentence. Do not speed the voice up until it is hard to follow.
• A word is mispronounced. Respell it phonetically and regenerate that sentence.
• The audio will not import. Save it to the Files app first, then import it into the editor from there.

For more on short-form scripts, see the TikTok voiceover use case and the guide to writing scripts for AI voices.