Subtitle checker
Check an SRT file for long lines, too many lines, fast reading speed, very short or long cues, and overlapping timing.
Runs in your browser. Your file is never uploaded.
What the subtitle checker looks for
The checks follow common broadcast and streaming guidelines: at most 42 characters per line, at most 2 lines per cue, a reading speed of at most 17 characters per second, and each cue on screen for between 0.833 and 7 seconds.
Overlapping cues make many players hide or stack lines, so they are listed with both cue numbers. Fix the problems in your editor, or open the file in Aivently, where the same checks run as you edit.
Questions
Are these rules mandatory?
No. They are common defaults. Some platforms and children's content use stricter limits.
How is reading speed counted?
Visible characters, excluding spaces, divided by the time the cue is on screen.
Does it check spelling or translation?
No. It checks layout and timing only.
More free subtitle tools
Subtitle converter
SRT, VTT, ASS, SUB, SBV, TTML and more to SRT, VTT, ASS, TXT or JSON.
SRT to text
Strip numbers and timecodes and keep only the dialogue.
Subtitle sync
Shift every line earlier or later, or convert frame rates.
SRT merger
Join two subtitle files, one after the other or by time.
Dual subtitles
Two languages on screen at once, from two SRT files.
Sample SRT files
Valid SRT, VTT and ASS examples to copy or download.
Need this file in another language?
Aivently translates SRT, VTT and ASS files with AI, keeps every timecode, and lets you review each line before export. New accounts get 10 free minutes.