Text File Encoding Detector

Upload a text file to find out what encoding it's actually in — UTF-8, Shift-JIS, EUC-JP, Windows-1252, GB18030, and more. Detection only — no conversion.

Drag & drop a file here, or click to browse

Runs automatically as soon as a file is selected.

When this helps

Developers

A file lands with no encoding declared and opening it garbles the text.

Upload it here first to find out what encoding it's actually in.

Accounting staff

Not sure if an old export is Shift-JIS or already UTF-8 before converting it.

Check the encoding here, then use the Shift-JIS ⇔ UTF-8 tool if a conversion is needed.

FAQ

Is my file uploaded to your servers?
No — if your browser supports WebAssembly (WASM, a technology that runs software safely and quickly right inside your browser), the file never leaves your device. If that isn't available, it falls back to normal server-side processing, which also discards the file immediately after returning the result — nothing is stored either way.
How accurate is this?
Encoding detection is a best guess, not a certainty — especially on very short files. The report includes a confidence level and any other plausible encodings so you can sanity-check the result.
Which encodings can it recognize?
A wide range — UTF-8/16/32, Shift-JIS/CP932, EUC-JP, ISO-2022-JP, GB2312/GB18030, Big5, EUC-KR/CP949, Windows-1252, and other common single-byte and CJK encodings.
What's the file size limit?
10MB per file on the free tier.