RandoziSubtitle Checker for SRT and VTT
Paste your subtitle file and get a table of every problem — overlaps, cues that flash by, text that reads too fast, lines that are too long — plus a summary. Nothing leaves your browser.
Issues found
10
1 errors · 9 warnings · 4 cues
- Format
- SRT
- Cues
- 4
- Average CPS
- 26.6
- Highest CPS
- 40.5
| Cue | Level | Problem |
|---|---|---|
| 2 | Error | Starts 500 ms before cue 1 ends. |
| 2 | Warning | Reads at 35.0 characters/s (limit 17). |
| 2 | Warning | Reads at 360 words/min (limit 200). |
| 3 | Warning | Lasts 400 ms (minimum 833 ms). |
| 3 | Warning | Reads at 22.5 characters/s (limit 17). |
| 3 | Warning | Reads at 300 words/min (limit 200). |
| 4 | Warning | Numbered 5, expected 4. |
| 4 | Warning | Longest line has 81 characters (limit 42). |
| 4 | Warning | Reads at 40.5 characters/s (limit 17). |
| 4 | Warning | Reads at 420 words/min (limit 200). |
Last cue ends at 00:00:08,000. Characters are counted without tags and line breaks.
How it works
- Paste the contents of your .srt or .vtt file into the box. A short sample is loaded to show how it works.
- Adjust the limits if your client or platform uses different ones: reading speed, duration, line length, number of lines.
- Read the summary, then go through the table of issues. Each row names the cue and what is wrong.
- Fix the cues in your subtitle editor and paste the file again until the table is empty.
What people use it for
Before delivery
Catch overlaps and numbering errors that make a streaming platform or a client reject your file.
Fast dialogue
Find the cues that viewers cannot finish reading, so you can trim the text or extend the timing.
Fan and community subs
Check a translated file for lines that run too long on screen before you publish it.
Questions
- How are CPS and WPM calculated?
- CPS (characters per second) is the number of characters in a cue, tags removed and line breaks not counted, divided by the cue duration in seconds. WPM (words per minute) is the number of words divided by the duration in minutes. A cue of 34 characters shown for 2 seconds reads at 17 CPS.
- Which default limits are used?
- 17 characters per second, 200 words per minute, a minimum of 833 ms (5/6 of a second) and a maximum of 7 seconds per cue, two lines of at most 42 characters. These are common adult-audience guidelines; your client or platform may require other values, so change them above.
- What counts as an overlap?
- A cue overlaps when it starts before the latest end time of the cues above it. Overlaps are reported as errors because many players show two cues at once or drop one of them. Cues that touch exactly (end = next start) are fine.
- Is my file uploaded?
- No. The file is parsed by your browser and is never sent, stored or logged.