Updated 2026-06-28

How to Hardcode (Burn) Subtitles Into a Video on iPhone

By the iPhone Captions editorial team · Updated 2026-06-28

“Hardcoding” or “burning in” subtitles means baking the text permanently into the video's pixels, so they appear on every player and every platform with no separate file. It's exactly what you want for social video.

How do I burn subtitles into a video on iPhone?

Use a captioning app that renders the text into the video and exports a new file. Hardcoded (burned-in) subtitles are part of the picture, so they always show — unlike a soft SRT that a player can turn off. In Subly you transcribe or add your captions, then export; the result is an MP4 with subtitles baked in.

Hardcoded vs soft subtitles

Hardcoded (burned-in): drawn into the video pixels. Always visible, can't be turned off, work on every platform. Best for Reels, TikTok, Shorts and anywhere captions must show.
Soft (SRT/VTT): a separate text file the player overlays. Can be toggled or restyled, but many social apps ignore them — so the captions just don't appear.

For social video you almost always want hardcoded captions, because most feeds autoplay muted and won't load an external subtitle file.

Burn captions in on iPhone

Import the video. Open your captioning app and select the clip.
Add the captions. Auto-transcribe the speech (Subly does this on-device) or type your lines, then fix wording and timing.
Style them. Pick size, position and look — keep them inside the safe area so platform UI doesn't cover them.
Export. Save a new video; the captions are now burned into the file and will show everywhere.

Already have an SRT file you want burned in? Not every iPhone app imports SRT — check the app's import options first. If yours doesn't, re-transcribe in the app (it's usually faster than retyping) and export burned-in.

Frequently asked questions

What does hardcoded subtitles mean?

Hardcoded (or burned-in) subtitles are drawn permanently into the video image, so they're always visible and can't be switched off. They're the opposite of a soft SRT file the viewer's player can toggle.

Why won't my SRT subtitles show on Instagram or TikTok?

Because those platforms don't read external SRT files for uploaded video. You need the captions burned into the video itself — hardcode them in an app before you upload.

Does burning in subtitles reduce video quality?

Only from the normal re-encode, which is minor. Export at the highest quality the app offers and keep captions inside the safe area so nothing important is cropped.

Written for iPhone users. App features and iOS steps can change between versions — check the latest before you rely on them. How we test & our sources →

How to Hardcode (Burn) Subtitles Into a Video on iPhone

Hardcoded vs soft subtitles

Burn captions in on iPhone

Frequently asked questions

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