A multi-format subtitle editor, timestamp synchronizer, quality auditor, and Matroska softsub muxer for Linux. A lightweight Linux alternative to Subtitle Edit for timing synchronization, CPS/overlap repair, and format conversion.

Key features powered by bundled FFmpeg:

• Native editing and lossless format conversion across SubRip (.srt), WebVTT (.vtt), and SubStation Alpha (.ass / .ssa), plus embedded subtitle track extraction from video containers.
• Interactive cue table displaying index, start/end timestamps, duration, reading speed in characters per second (CPS), and line length with a live cue editor and 42-character auto-wrapper.
• Batch timestamp synchronization via millisecond time-shift (+/- ms) and frame-rate (FPS) stretching across 23.976, 24, 25, 29.97, 30, 50, and 60 fps.
• Automatic Quality & Error Inspector detecting and fixing overlapping timestamps, >25 CPS fast lines, >42-character long lines, and legacy text encodings.
• Visual video frame sync preview at any subtitle cue and lossless Matroska (.mkv) soft-subtitle multiplexing.

Disclaimer: This project is an independent open-source tool and is not affiliated with, sponsored by, or endorsed by Nikse or the Subtitle Edit project.