Fix garbled subtitle encoding
Subtitles turn into gibberish when the file’s encoding and the player’s assumption disagree. This tool detects the original encoding and rewrites the file as UTF-8.
Why subtitles get garbled
Japanese subtitle files are often saved as Shift_JIS (CP932), while VLC, YouTube and the HTML5 <track> element assume UTF-8. The mismatch produces the familiar mojibake. A UTF-16 file that appears to have a space between every character is the same problem seen from the other side.
How to use it
Choose the subtitle file and the tool reads the BOM and the byte patterns to identify the encoding, showing its confidence and a preview of the decoded text. If the preview reads correctly, press Convert to save it as UTF-8; if not, pick the encoding by hand.
With or without a BOM
Subtitles are normally UTF-8 without a BOM. Add one only if you plan to open the file in Notepad or Excel. Players read either, but a few older ones mistake the three BOM bytes for part of the first cue number.
Frequently asked questions
Can I paste text that is already garbled?
No — mojibake is the result of decoding bytes the wrong way, so the original bytes are needed. Load the original .srt through the file picker instead.
The detected encoding looks wrong.
Select Shift_JIS, EUC-JP or UTF-16LE explicitly in the source encoding list and check the preview until the text reads correctly.
Some characters disappear after conversion.
Writing back to Shift_JIS cannot represent emoji and some rarer kanji, and you get a warning listing them. Saving as UTF-8 preserves everything.
Are my files uploaded to a server?
No. Everything runs as JavaScript inside your browser and the file contents never leave your machine, which makes it safe for unreleased scripts and confidential recordings.