Subtitle file diagnostics
Subtitle Encoding Checker
Diagnose common text-encoding symptoms before a subtitle file reaches your player or editor. The checker reports damaged replacement characters, hidden null bytes, normalization and line-ending details.
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Tool workspace
No account required · processed locally
Three steps
How this tool works
- 1
Paste text from an SRT or VTT file.
- 2
Inspect visible and hidden encoding signals.
- 3
Use the report to decide whether to re-export as UTF-8.
Useful for
Common workflows
- Broken regional-language captions
- Subtitle import troubleshooting
- UTF-8 delivery QA
What it checks
Focused, transparent output
- Unicode replacement characters
- Null bytes and BOM
- NFC normalization and line endings
Questions
Frequently asked questions
Can a browser identify the original file encoding with certainty?
Not after text has already been decoded. This tool detects common damage signals and Unicode structure, not the original byte encoding.
What does the replacement character mean?
The symbol � often indicates bytes could not be decoded correctly.
What encoding should I export subtitles with?
UTF-8 is the safest general choice for Indian scripts and multilingual captions.