Does it handle Unicode and emoji correctly?

Yes. The encoder uses encodeURIComponent() before btoa() to handle multi-byte UTF-8 characters. Many simpler tools fail on characters outside the Latin-1 range — this one does not.

What happens if I try to decode an invalid Base64 string?

The tool catches the error from atob() and displays 'Invalid Base64 string.' in red. Common causes are missing padding (= characters) or characters outside the Base64 alphabet.

Can I encode images with this tool?

This tool encodes text strings only. For converting an image file to a Base64 data URL, use the dedicated Image to Base64 tool on ToolBrigade.

Does it support URL-safe Base64?

No. Standard Base64 uses + and / which are not URL-safe. URL-safe Base64 replaces those with - and _. This tool outputs standard Base64 only.

Base64 Encoder / Decoder

Encode plain text to Base64 or decode Base64 strings back to readable text instantly.

How to use this tool

1Paste your plain text or Base64 string into the left 'Input' textarea.
2Click Encode to convert plain text to Base64, or Decode to convert Base64 back to plain text.
3The result appears in the right 'Output' textarea — select all and copy it from there.
4If decoding fails (invalid Base64), a red error message appears below the buttons.

About Base64 Encoder / Decoder

Base64 encoding turns arbitrary text or binary data into a string of 64 printable ASCII characters, making it safe to embed in JSON payloads, HTTP headers, data URLs, and email bodies that can't handle raw binary. This encoder uses btoa() with a UTF-8 pre-encoding step (encodeURIComponent + unescape) so it correctly handles non-ASCII characters like accented letters, emoji, and CJK text — a common failure point in naive implementations. The decoder reverses the process using atob() with the same UTF-8 unwrapping. Paste your plain text on the left, click Encode, and the Base64 string appears on the right. To decode, paste a Base64 string and click Decode. If the input is not valid Base64, an error message is shown immediately. Typical uses include encoding Basic Auth credentials (username:password) before adding them to an Authorization header, inspecting JWT payloads, and embedding small text blobs in HTML data attributes.

Frequently asked questions

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