Subtitle Validator
Lint your subtitles for issues that break players or look unprofessional.
Drop your subtitle file here, or click to browse
SRT, VTT, ASS, SMI, TTML, SBV, LRC, MicroDVD, SubViewer
Frequently asked questions
What does the validator check?
Cue duration (200ms–12s window), line count (≤3 recommended), line length (≤80 chars), overlap with the previous cue, and parser warnings (encoding, malformed timing).
My file passed but the player still won’t show subtitles.
Likely a player-side codec or container issue, not a subtitle issue. Try the Universal Converter to switch to VTT, which has the broadest player support.