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🎞️ Subtitle (SRT) Shifter

Paste or load an .srt file, apply a time shift in seconds (+/-) and optionally rescale the frame rate, then copy or download the corrected subtitle file — all in your browser, no upload needed.

SRT subtitles

About

This tool parses every timestamp in a standard SubRip (.srt) file and applies two independent corrections. A time shift adds or subtracts a fixed offset (e.g. +2.5 s or -0.8 s) to every cue, letting you push all subtitles forward or backward to match the audio track. A frame-rate rescale multiplies every timestamp by the ratio of the target FPS to the source FPS, correcting drift that accumulates when a video is encoded at a different frame rate than the subtitle was authored for (for example, converting a 25 fps PAL subtitle to 23.976 fps NTSC). Both corrections can be applied together in one pass. Processing happens entirely in your browser — your subtitle text never reaches any server.

How to use

  1. Paste your .srt content into the text area, or click Load File to open an .srt file from your device.
  2. Enter a time shift in seconds — use a positive value to delay subtitles, or a negative value to make them appear earlier.
  3. Optionally select the original and target frame rates (e.g. 25 → 23.976) to correct FPS-related timing drift.
  4. Click Apply Shift to process the file. The corrected subtitle text appears instantly in the output area.
  5. Copy the result to clipboard or click Download .srt to save the corrected subtitle file to your device.

FAQ

What does the time shift value mean?
It is added to every timestamp in the file. Enter +2.5 to delay all subtitles by 2.5 seconds, or -1 to make them appear 1 second earlier.
When should I use frame-rate rescaling instead of a plain time shift?
Use rescaling when the subtitle drift increases over time — e.g. it is off by 1 s at minute 10 but 5 s at minute 50. This indicates an FPS mismatch between the subtitle and the video file.
Is my subtitle file uploaded to a server?
No. All processing happens entirely in your browser. Your subtitle text never leaves your device.
Which frame rates are supported for rescaling?
The tool supports conversions between 23.976 fps (NTSC film), 24 fps, and 25 fps (PAL). These cover the vast majority of subtitle sync issues caused by FPS mismatches.
Can I apply a time shift and a frame-rate rescale at the same time?
Yes. The tool first applies the frame-rate rescale to correct drift, then adds the time shift to fix any remaining global offset — both in a single pass.