Character Encoding and Broken Korean: Why It Happens and How to Fix It
Broken text almost always comes from an "encoding mismatch." CSV and text files created on older Windows systems are often saved as EUC-KR (or its superset CP949). When modern apps (Excel, Google Sheets, VS Code) assume UTF-8 and read them, the characters appear garbled. The "Fix File" tab reads the raw bytes, interprets them with several encodings, and restores the original once you pick the right one.
Auto-detection works by checking for a BOM (byte order mark), validating UTF-8, and scoring candidate encodings by their ratio of Hangul/CJK/Kana characters versus replacement characters (�). It is not perfect, but it reliably guesses most Korean files saved as EUC-KR/CP949. If the guess is wrong, pick another encoding from the list and compare instantly in the live preview.
Text that already looks like "우리" on screen is repaired in the "Fix Mojibake" tab. This pattern usually appears when UTF-8 bytes were misread as Windows-1252/Latin-1; the tool maps the visible characters back to bytes and re-decodes them with the actual charset (UTF-8, EUC-KR, etc.). Everything runs inside your browser, so even sensitive data stays private.
Know the limits, too. The browser standard API only encodes to UTF-8, so this tool is optimized for "read many encodings → save as UTF-8." Re-saving UTF-8 back into EUC-KR is limited with standard features. Still, the most common real-world need — reviving a broken file as UTF-8 — is handled completely.