How to add captions to a video on iPhone.
Most people watch video on mute, so captions are no longer optional — they lift watch time and make your work accessible. Here are your real options on iPhone, the burned-in vs SRT decision, and how to caption so it actually reads well.
First, your options
- Apple's built-in tools. Photos can show live captions for accessibility, but it does not bake captions into an exported file. iMovie and Clips can add titles or basic captions manually, which is slow for a full script.
- A dedicated captioning app. This is the fast path: the app transcribes your audio, word-syncs the text, and lets you style and export. Quality varies in how well it syncs and whether it works offline.
- Desktop editors (Premiere, CapCut desktop) do this well but pull you off your phone and out of a quick mobile workflow.
Burned-in vs SRT: which to choose
This is the decision that trips people up, and it depends on where the video is going.
- Burned-in (open captions) are rendered into the video pixels, so they always show and can't be turned off. Use these for TikTok, Reels, and Shorts, where most viewing is muted and you want the captions guaranteed on screen.
- Sidecar SRT or VTT (closed captions) is a separate text file you upload next to the video. The platform can toggle it, style it, and even auto-translate it. Use this for YouTube, course platforms, and anywhere captions need to be optional or accessible.
The honest answer for a lot of creators is "both": burn them in for the social cut, and keep an SRT for the YouTube upload.
How to caption so it actually reads
Auto-generated captions are only as good as their timing and styling. A few rules that make the difference:
- Word-sync, not block-dump. Captions that highlight the current word (karaoke style) are far easier to follow and hold attention longer than a paragraph that appears all at once.
- Short lines, big text. One to four words per line, a large readable font, and a background or outline so it survives over any footage.
- Proofread the transcript. Names, jargon, and homophones are where auto-captions slip. A 30-second read-through saves an embarrassing typo on screen.
NexCam generates word-synced captions on your iPhone (your audio never leaves the phone), with eight styles including bold karaoke, then lets you burn them in or export SRT and VTT — in the same app you recorded in. It's step six of the full workflow.
Frequently asked
Can iPhone add captions to a video automatically?
Photos shows live captions for accessibility but doesn't bake them into an export. To add captions that travel with the file, use an app that transcribes and renders them, then burns them in or exports an SRT/VTT.
Burned-in or SRT — which should I use?
Burned-in for muted social feeds (TikTok, Reels, Shorts) where they must always show. SRT/VTT for YouTube and course platforms where captions should be toggleable, stylable, and translatable. Many creators do both.
Do captions actually help?
Yes — most social video is watched on mute, so captions lift watch time and completion, and they make your content accessible.