Base64 Decoder – Decode Base64 Encoded Data Online




About our Base64 Decoder

Our Base64 Decode and Encode, a simple and easy online tool that does exactly what it says:

Decodes from Base64 encoding. Encodes into it swiftly and easily. Base64 encodes your data without trouble or decodes it into user-friendly readable format.

Base64 encoding systems are commonly used when there is a requirement to encode binary data, particularly when that data needs to be collected and exported over media that are designed to deal with text. This Base64 encoding helps to assure that the data remains intact without adjustment during transport. Base64 is normally used in various applications as well as collecting complex data in XML or JSON.

Quick answer

Paste Base64-encoded text and the tool instantly decodes it back into the original text.

Key facts

  • Runs entirely in your browser via JavaScript's built-in Base64 functions|Decodes standard Base64-encoded text (A-Z, a-z, 0-9, +, /)|No file upload or server round-trip involved|Free with no usage limit|Invalid Base64 input will fail to decode correctly

What is this tool?

This tool decodes Base64-encoded text back into its original form, useful when you have Base64 data (such as an API token or embedded value) and need to see the original text.

How to use it

Paste your Base64-encoded text; the decoded original text appears instantly, ready to copy.
  1. Paste the Base64-encoded text you want to decode.|The tool instantly displays the decoded original text.|Copy the decoded result.

Example

Example: decoding "SGVsbG8=" produces the original text "Hello".

How it works

The page uses the browser's built-in Base64 decoding functions (such as `atob`) to convert your encoded text back into its original bytes/text, entirely in your browser.

Common use cases

Decoding an API token or credential to inspect its value.|Reversing Base64-encoded data embedded in a URL or JSON payload.|Learning or testing how Base64 decoding works.|Debugging systems that use Base64-encoded values.

Benefits

Free, instant, and requires no software installation.

Limitations

The input must be valid Base64 (correct character set and padding) -- malformed or truncated Base64 strings will fail to decode correctly or produce an error.

Privacy & your data

Decoding happens entirely in your browser using JavaScript's built-in Base64 functions. Your input is not sent to or stored on the A2Z Tools server.

Frequently asked questions

What if my Base64 input is invalid?
Malformed or incorrectly padded Base64 text will fail to decode correctly -- double-check that you copied the complete, correctly formatted string.
Can this decode Base32 text too?
No. Base32 and Base64 use different alphabets and encoding schemes -- use the dedicated Base32 decoder for Base32-encoded text.
Is my text sent to a server?
No. Decoding happens entirely in your browser; your input is not sent to or stored on the A2Z Tools server.
Is this tool free to use?
Yes, it's free with no signup required.

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