SRT Duration Adjuster

Captions are too quick to read, or they linger too long. The SRT Duration Adjuster resizes every cue.

Scale multiplies each duration by a factor — 0.8 to shorten, 1.2 to lengthen. Add shifts each end by a fixed number of milliseconds. You can also enforce a minimum and maximum duration so nothing is unreadable or endless. Only the end time changes; the wording and start are preserved. Paste your SRT and tune the timing.

• Scale mode: factor-based resizing.
• Add mode: fixed ms shift per cue.
• Min/Max clamp: readable, consistent lengths.
• Start preserved: only ends move.
• Lossless text: wording unchanged.
• Private: runs in your browser.

1. Paste your SRT (sample preloaded).
2. Pick a mode and enter a factor, ms, or min/max.
3. Click Adjust Duration and copy or download.

Example 1 — Too fast. Scale 1.25 to give readers more time.

Example 2 — Too slow. Scale 0.9 to tighten pacing.

Example 3 — Consistent. Min 1.5s, max 6s clamp.

• Readable: enforces minimum time.
• Consistent: caps runaway cues.
• Flexible: scale or add.
• Lossless: text preserved.
• Private: nothing uploaded.