RapiToolbox

Subtitle UTF-8 BOM Converter

Drag & drop your .srt or .vtt files here or click to select

Max 50 files | Up to 2MB per file

Why do subtitles show corrupted accents in MKVToolNix?

When multiplexing external subtitle files (.srt or .vtt) into MKV containers, tools like MKVToolNix often read standard UTF-8 files using local system encodings, causing special characters, tildes (á, é, í), and ñ to break. Adding a Byte Order Mark (BOM) forces complete compatibility.

Features & 100% Privacy

  • Local Processing: Your subtitle files never leave your browser; conversion happens instantly on your device.
  • Encoding Intelligence: Automatic fallback from strict UTF-8 to Windows-1252 (ANSI) prevents accent and symbol corruption.
  • Batch Support: Drop up to 50 files (2MB each) to convert them simultaneously with Windows CRLF line endings.
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