Free language tools

Lightweight, private tools that run in your browser. Built for learners who study from video and subtitle files.

• Add furigana to Japanese subtitlesAnnotate kanji with furigana or export an SRT with inline readings.
• Clean subtitle text for studyStrip timestamps, indices, and HTML from SRT/VTT into clean study text.
• Add pinyin to Chinese textAnnotate Chinese with pinyin tone marks; Simplified / Traditional toggle.
• Count word frequency in subtitlesRank unique words in subtitle or transcript text by frequency.
• Convert subtitles to Anki cardsTurn subtitle lines into an Anki-import TSV (Basic Front/Back).
• Align dual-language subtitlesMerge two SRTs into one bilingual file aligned by cue timing.
• Filter kanji by JLPT or gradeColor-code kanji by JLPT N5–N1 or jōyō / kyōiku grade.
• Scan Hanzi by HSK 3.0 levelHighlight Hanzi by HSK 3.0 bands with a percent breakdown.
• Romanize Hangul for studyHangul → Revised Romanization or jamo phonetic breakdown.
• Extract conjugated Japanese verbsScan Japanese text/SRT for conjugated verbs and dictionary forms.
• Unpack Korean verb endingsConjugated Korean → dictionary form with tense / honorific steps.
• Parse Hangul into jamoHangul blocks → jamo parts with sound-change notes.