Subtitles, resynch'ed.


  • 2020.05.31

    New design. New conversion feature. New cleaning feature. Now supports .vtt files. All files are now truly encoded in UTF-8.

  • 2020.05.11

    [FIXED] Carriage returns being skipped in .srt files. Thanks Johnny!

  • 2018.01.15

    [FIXED] Incorrect time shifting when using decimals. Thanks Benjamin!

  • 2017.11.28

    [ADDED] Filesize limit increased.

  • 2017.11.15

    [FIXED] Line feeds being skipped in .srt files. (currently monitoring) Thanks Yvonne!

  • 2017.03.28

    [ADDED] More format flexibility on .srt files.


SubSyncer is a free online tool able to edit subtitles in any languages and in the most popular subtitles formats. With SubSyncer you can:

  • Re-synchronize (FPS to FPS)
  • Shift time
  • Convert to other file formats
  • Clean cues

You can also use the link provided to share your subtitles with others!

Ease of use & Flexibility. No need to worry about your file format. All features support all below subtitle file formats:

  • .srt
  • .vtt
  • .ass
  • .ssa
  • .sub

Even better, Subsyncer will now tell you if your file is not in the proper format!


Subtitles are slowly becoming out of sync?
This is due to the number of frames per second (FPS) of videos that will result in subtitles become slightly delayed over time. This tool gets the FPS of the original subtitle file and changes all cues' timings according to your video's FPS.

Supported formats: ALL (.srt, .vtt, .ass, .ssa, .sub)

Time Shifting

All cues are out of sync by the same interval?
This may be due to your video being cut shorter or longer at some places. This tool can shift all cues by the same time interval at once. You can choose to fasten or delay all cues in milliseconds, and shift the subtitles until it fits your video.

Supported formats: ALL (.srt, .vtt, .ass, .ssa, .sub)


Different video players support different file formats.
Or it could be that you want more flexibility using one format over another. SubSyncer has the tool that can convert your subtitle files to the format that you want. If possible, it will also automatically translate all syntaxes to fit the new file format!

Supported formats: ALL (.srt, .vtt, .ass, .ssa, .sub)


Syntaxes are specific to subtitle file formats.
Some files may have wrong syntaxes or may include closed captions. Using the cleaning tool, SubSyncer allows you to remove closed captions and all syntaxes that may not be suitable to your subtitle file. You can decide what to keep or what to remove.

Supported formats: ALL (.srt, .vtt, .ass, .ssa, .sub)

About SubSyncer

This was originally a personal project that originated from my own need in having such tools without downloading any software. I decided to make it public and free of use so that everyone can enjoy this tool.
I am always looking to improve the website/algorithm further so if you have any problem, feedback or suggestion please send me an e-mail. I will answer within 48 hours.

About SubSyncer

Privacy and
Personal Informations

This website does not record any browsing informations. Subtitle files are uploaded upon submission and temporarily saved for 60 days on the server. Files will not be shared with other third-party websites and may only be used to improve this tool's accuracy.