YouTube subtitle file garbled? Save it as UTF-8, or burn captions

YouTube says caption files should be plain UTF-8 text. If an uploaded subtitle file shows accents, Hangul, or other non-English characters as boxes or odd symbols, the first thing to check is the file's encoding: re-save it as UTF-8 and upload again. If you would rather the captions not depend on a file at all, Sume's video captions burns them into the video, for Latin and Hangul text.

The YouTube facts come from Upload subtitles and captions, read on 2026-10-02.

Which subtitle formats does YouTube take?

The page groups them. Basic formats include SubRip (.srt), SubViewer (.sbv or .sub), MPsub, LRC, and Videotron Lambda (.cap). Advanced formats with styling include SAMI, RealText, WebVTT (.vtt), and TTML (.ttml). Broadcast formats include Scenarist Closed Caption (.scc) and EBU-STL (.stl), among others. YouTube recommends SubRip or SubViewer for newcomers.

How do you fix garbled characters?

Open the file in an editor that shows and sets the encoding, save it as UTF-8, and confirm the file extension still matches the format inside. Do a quick check on one line with the characters you worry about: an accented letter, a Hangul syllable, an emoji. If those look right in the editor, they should upload correctly.

This is a file problem, not a language problem. YouTube names UTF-8 plain text as the expected encoding, so a file saved in another encoding is the likely cause when characters break. The page does not describe a specific garble symptom, so treat this as the first thing to rule out, not a guaranteed cure.

When is burning captions the better route?

A sidecar file keeps captions switchable and lets the viewer's player pick the font. A burned caption is pixels: it always shows, and it fits platforms that take no caption file, such as a Short you reshare. The cost of burning is that it cannot be turned off and the language is fixed per file.

What does Sume cover?

The Video captions page documents burning onto a public HTTPS video, with cues or segments you supply, or speech-to-text when you omit them. Latin styles (slam, punch, tiktok-green) and Hangul styles (such as black-outline) are documented. A caption job costs $0.20 for a video up to 60 seconds.

The docs say SRT uploads are unsupported as input and describe no caption file export, so Sume does not produce your sidecar. Pass the phrases as cues with text, start, and end. For Japanese, Chinese, or Arabic the docs list no face, so test one clip first.