Voice-over (VO) is a production technique in which a recorded narration or spoken audio track is laid over visual content, with the speaker not visible on screen. The voice-over provides information, context, storytelling, or emotional framing that accompanies the imagery without requiring the speaker to be physically present within the scene being shown.

Voice-over serves a wide range of functions across different content types. In documentary filmmaking it provides narration that guides the viewer's understanding of the images being shown. In advertising it delivers messaging and calls to action over product or lifestyle footage. In narrative film it can provide a character's internal monologue, establish backstory, or create an intimate storytelling register that feels more literary than purely visual. Corporate and explainer content relies heavily on voice-over to walk audiences through information while relevant visuals play alongside. The quality of a voice-over recording - microphone, acoustic environment, delivery style, and pacing - has an enormous impact on the professional feel of the finished content, making it one of the areas where investment in quality yields the most visible returns.

AI voice synthesis tools have made high-quality voice-over production significantly more accessible, allowing creators to generate narration from text without recording sessions, and to iterate on pacing and delivery quickly. When assembling AI video projects, pairing generated visual content with either recorded or synthesized voice-over in post-production is one of the most effective ways to add narrative clarity, emotional direction, and professional polish to a sequence.