Add Voiceover, Music, and Captions

Silent video is only half a video. Audio and captions are what make a clip feel professional and keep viewers watching — especially on social, where most people scroll with the sound off. This lesson shows you how to add AI voiceover, background music, and readable captions without any audio-editing experience.

What You'll Learn

• How to create an AI voiceover from your script
• How to choose and add background music that fits the mood
• Why captions are essential and how to add them fast
• How to balance the three audio layers so nothing clashes

The Three Layers of Sound

Good short video usually has three audio layers:

1. Voiceover (narration) — carries the message.
2. Background music — sets mood and energy.
3. Captions (on-screen text) — makes it watchable without sound.

You don't always need all three. A moody atmosphere clip might be just music. A tutorial might be voiceover plus captions. But knowing how to layer them gives you options.

Creating an AI Voiceover

You wrote a script in the last lesson — now give it a voice. Options:

• Canva's built-in Text to Speech / AI voice features — paste your script, pick a voice, and it generates narration right in your project.
• Dedicated AI voice tools (like ElevenLabs and similar) — more natural-sounding voices with a free tier; export an audio file and import it into Canva.

Tips for natural narration:

• Write for the ear. Short sentences. Contractions ("you'll," "it's"). Read your script aloud first — if you stumble, rewrite it.
• Add commas and periods where you want pauses; punctuation controls pacing.
• Pick a voice that matches the mood — warm and calm for wellness, upbeat for tips, confident for business.

Ask a chatbot to polish narration for voice:

"Rewrite this script to sound natural when read aloud by an AI voice for a 25-second Reel. Use short spoken sentences, contractions, and natural pauses. Keep it under 65 words: '[paste script]'."

Choosing Background Music

Music sets emotion before a single word lands. In Canva:

1. Open the Audio tab in the sidebar.
2. Search by mood ("upbeat," "calm," "cinematic," "corporate").
3. Preview and drag a track onto your timeline.
4. Trim it to your video length and fade it out at the end.

Rules that keep it professional:

• Music supports, never competes. Lower music volume when there's narration.
• Match energy to content — a finance tip isn't a dance track.
• Watch licensing. Use Canva's included audio or clearly royalty-free/licensed music, especially if you'll post publicly or monetize.

Adding Captions (Do Not Skip This)

Most social video is watched on mute. Captions aren't optional — they're how your message survives the silent scroll. They also boost accessibility and watch time.

In Canva:

• Use the auto-captions / "Captions" feature to transcribe your voiceover automatically, then fix any errors.
• Or add text elements manually per scene (you may already have caption lines from your script).
• Keep captions short (3–6 words per line), high-contrast, and near the center or lower third — but not so low they're hidden by platform UI.

Style tips: bold sans-serif font, a subtle background bar or outline so text stays readable over any footage, and animate them in with a simple preset.

Balancing the Mix

When you have all three layers:

• Narration is loudest and clearest.
• Music sits underneath — roughly a third of the narration's volume when someone's speaking.
• Captions match the narration word for word so muted viewers get the same message.

Play the whole thing with headphones. If you have to strain to hear the words over the music, turn the music down.

Your Exercise

1. Take your explainer script from the last lesson.
2. Generate an AI voiceover (Canva or a free voice tool) and add it to your project.
3. Add a background music track that matches the mood; trim and fade it.
4. Add captions — auto-generate them, then correct any mistakes.
5. Watch it once with sound and once muted. Does it work both ways? Fix whatever doesn't.

Certificate Reminder

Knowing how to layer voice, music, and captions is what separates amateur clips from shareable content. This free course's free certificate signals you can deliver finished, platform-ready video — not just raw clips.

Key Takeaways

• Short video has three audio layers: voiceover, music, and captions — use what the piece needs.
• Generate natural AI narration by writing for the ear and picking a mood-matched voice.
• Music should support, not compete; trim, fade, and mind licensing.
• Captions are essential because most social video is watched muted — keep them short and high-contrast.
• Balance the mix so narration leads, music sits underneath, and captions match the words.