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Base64 decode
Paste Base64 and read the original text right away. Missing padding, line breaks and URL safe characters are handled for you, and if the data is a file you can preview and download it.
Free and private. Everything runs in your browser, nothing is uploaded.
Base64
TXT
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How it works
Paste your textType or paste into the input box, or open a text file. Sample shows an example.
Check the resultThe result appears on the right as you type. Errors are shown with the line and column.
Copy or swapCopy the result, download it as a file, or press Swap to reverse the direction and check it.
Decode anything that looks like Base64
API responses, email sources, configuration files and JWT tokens often contain Base64. Paste it here to see what is inside. Data URIs that start with data: are accepted as they are.
When the decoded data is an image, a PDF or a ZIP archive, the tool says so, shows images as a preview and lets you save the file with the right extension.
About Base64
Base64 writes binary data using 64 safe characters: A to Z, a to z, 0 to 9, + and /. Every 3 bytes become 4 characters, so the result is about a third larger than the original.
Frequently asked questions
Why do I get an invalid character error?
Base64 only contains letters, digits, +, /, - and _. The error points to the first character that does not belong, which is often a quote or a stray symbol copied by mistake.
Is my text uploaded anywhere?
No. Encoding and decoding happen in your browser. Tokens, keys and other private text never leave your device.
Is Base64 encryption?
No. Base64 only changes how data is written. Anyone can decode it, so never use it to protect passwords or secrets.
What is URL safe Base64?
It replaces + and / with - and _ and drops the = padding, so the result can be used in addresses and file names. It is used in JWT tokens, for example. The decoder accepts both forms.
Why does decoding show a file instead of text?
If the decoded data is not readable text, the tool checks what kind of file it is. Images are previewed, and any file can be downloaded with the Download button.
Does it work offline?
Yes. After you open the page once, it keeps working without an internet connection.