Base64 Decoder
Decode Base64 to text online for free — correctly handles Vietnamese, emoji, and other Unicode text. Nothing uploaded to a server.
Your files are processed locally in your browser and are not uploaded to our servers.
How to use Base64 Decoder
- 1
Paste a Base64 string into the box.
- 2
Click "Decode."
- 3
Copy or download the decoded text.
Common uses
- Reading the actual content of a Base64-encoded API token or config value
- Decoding a data URL's payload to inspect it
- Checking what a Base64 string someone sent you actually says
Supported formats and limitations
Accepts text, up to one file at a time.
- Invalid Base64 (wrong characters, broken padding) is rejected with a clear error rather than producing garbled output.
- This decodes to text — a Base64 string that represents binary data (like an image) will decode to unreadable characters, since it was never text to begin with.
Frequently asked questions
You'll see "Invalid Base64 string" rather than garbled or silently wrong output.
Yes — decoding goes through proper UTF-8 byte conversion, so Unicode text decodes back exactly as it was encoded.
No. Decoding happens entirely in your browser.
No — Base64 isn't encryption, and anyone with the encoded string can decode it just as easily. It provides no confidentiality.