Base64 Decoder
Decode Base64 into readable UTF-8 text in the browser, with invalid-data feedback.
Free browser tool
No Matrix computer needed
✓ No account or card
✓ Use the result right away
✓ Task-specific limits below
Workspace
Use base64 decoder
Runs in this browser tab
Result
How to use it
Paste a Base64 value to see its decoded UTF-8 text before using it.
Try this example
SGVsbG8sIE1hdHJpeCBPUyE=
What to check
Binary data that is not valid UTF-8 cannot be displayed as text here.
Review the result before using it in a published page, application, or agent configuration.
Quick answers
Frequently asked questions
Why can a Base64 value fail to decode as text?
The decoded bytes must be valid UTF-8. Binary files and malformed Base64 are rejected because this tool displays text rather than arbitrary bytes.
Does Base64 decoding check whether content is safe?
No. It reveals the encoded text but does not establish trust. Treat decoded scripts, links, and credentials as untrusted content.
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