Base64 Encoder / Decoder
Encode and decode UTF-8 text to base64 and back. Swap modes in one click and catch malformed input with a friendly explanation.
UTF-8 is fully supported. Unpadded base64 is not accepted — the decoder explains why.
About the Base64 Encoder / Decoder
Encode and decode UTF-8 text to base64 and back. Swap modes in one click and catch malformed input with a friendly explanation.
Encoding and decoding happen entirely in the browser.
How to use the Base64 Encoder / Decoder
- Step 1Choose Encode or Decode, or jump between them with Swap.
- Step 2Type or paste your text (any language works).
- Step 3Press the action button to get the result, then copy it.
When people reach for this tool
Carry a small string through a query parameter
Base64 handles characters that would otherwise break a link, such as plus signs, ampersands and line breaks.
Build the encoded value for an API request
The username and password pair goes into a header as a single base64 string, which is quicker than assembling by hand.
Encode a text snippet for a form field
Fields that expect a single-line string often reject raw multi-line content, and encoding avoids that.
Practical tips
- Base64 is an encoding, not encryption. Anyone can decode it, so never use it to hide a password or a secret.
- Decoding expects the exact original text. Extra whitespace added while copying is usually tolerated, but anything else is not.
What you get
- Encode and decode text with full UTF-8 support
- One-click mode swap
- Friendly errors for malformed base64
- Copy and clear actions
- Good for sharing or embedding small text blocks
Base64 Encoder / Decoder — FAQ
Does it support Unicode?
Why does decoding fail?
Is base64 encryption?
Why does my decoded text look wrong?
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