Korean → Japanese
To translate Korean subtitles to Japanese, upload your .srt or .vtt file to SubLingo, set the target language to Japanese, and download the file with every timecode preserved. Japanese collapses to far fewer characters than Korean (roughly 20% shorter on a character basis) but each glyph is full-width, so lines stay capped at 13 characters. Japanese mixes kanji and kana with no spaces, so Netflix caps horizontal lines at 13 full-width characters and just 4 cps. Keep each line under 13 characters and a reading speed below 4 characters per second — the limit Netflix sets for Japanese subtitles — and save the file as UTF-8 so every character survives the round trip.
Last updated: 2026-06-11
Drop your subtitle file here, or click to browse
Supports .srt, .vtt, and .ass / .ssa
Drop in your Korean .srt or .vtt file. SubLingo parses every cue and locks the timings in place.
Set the target language to Japanese. The source is auto-detected, so you can leave it on Korean or let it detect.
Run the translation. Only the text inside each cue is rewritten in Japanese — never the timecodes.
Download the Japanese subtitle file in the same format you uploaded, ready to drop straight onto your video.
Translating from Korean into Japanese: Japanese collapses to far fewer characters than Korean (roughly 20% shorter on a character basis) but each glyph is full-width, so lines stay capped at 13 characters. Japanese mixes kanji and kana with no spaces, so Netflix caps horizontal lines at 13 full-width characters and just 4 cps. Because SubLingo rewrites only the text inside each cue, every timecode from the original Korean file carries over to the Japanese version unchanged.
Need the other direction? Translate Japanese subtitles to Korean.
Netflix caps Japanese subtitles at 13 full-width characters per line and a reading speed of about 4 characters per second, across a maximum of two lines. SubLingo keeps the cue boundaries fixed, so you can re-break a long Japanese line without touching the timing.
No. SubLingo translates only the subtitle text, so every start and end time is preserved exactly. Your Japanese subtitles stay frame-accurate against the original video.
Yes. Both WebVTT (.vtt) and SubRip (.srt) Korean files are supported, including multi-line cues. The output keeps the same format you uploaded.
Yes. You can translate a Korean subtitle file to Japanese in your browser for free, with no signup and nothing to install.
You can try it for free with no account. Upload your Korean file, translate to Japanese, and download the result.
Most Korean subtitle files translate to Japanese in a few seconds. Longer files with thousands of cues take a little more, but you stay on the page the whole time.
Typical movie and episode subtitle files — a few hundred KB and a few thousand cues — translate without trouble. Very large files may take longer to process, but the timecodes still come back unchanged.