How to add subtitles to a video on iPhone

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In VDIT, tap Captions to generate subtitles from speech. For text you want to write yourself, use the manual text tools. Review the wording, match each caption to the audio, and check its position before exporting.

Automatic captions are useful for dialogue and narration. Manual text works well for a short line, a title, or wording that is not spoken in the video. Both help viewers follow your content when they cannot hear the audio.

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Generate subtitles with Captions

Open your video in VDIT and tap Captions in the editing toolbar to start creating automatic captions from speech.

VDIT's Captions menu highlighted in an automatic-caption introduction screen. — Tap Captions to start. The image shows the feature’s introduction screen.

Once captions are generated, listen to the audio while reading each line. Correct words that do not match the speaker, including names or product names. If a line is missing or has the wrong meaning, fix it before styling the captions.

For more about this feature, see our VDIT automatic-caption guide.

Add subtitles manually

Select your clip and tap Text. Type the line you want to display, then adjust its timing, position, and style.

VDIT editing toolbar with the Text menu highlighted.

Set the text to appear when that line is spoken and disappear when it ends. For a title or a short message without speech, leave enough time to read it at the video’s normal speed.

A selected text layer in VDIT, with text editing tools and its duration visible on the timeline.

Repeat for the remaining lines. Manual text also lets you add a phrase or title that is not part of the recorded speech.

Check timing and readability

Play the video with sound and check when each line appears and disappears. If the timing is off, adjust the caption’s timing and play that section again.

Then watch with the sound off. Check whether you can read each line before it changes. Break up long lines where the wording allows, and choose a size and position that remain readable against the footage. Keep text away from important faces or details.

If you plan to post to a social app, check that app’s preview too. Buttons or interface text may overlap captions near the edges of the frame.

Export and review the saved video

Save the finished video and open it in Photos. Watch it from beginning to end to check for missing lines, spelling errors, or captions that disappear too quickly. Return to the project and correct any problems before sharing.

This check is useful for both automatic and manual subtitles. Automatic generation gives you text to review; you still decide whether it accurately represents what was said.

To follow these steps, download VDIT on the App Store.