Base64 Decoder

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Decode Base64-encoded text back to its original string.

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About Base64 Decoder

Paste any Base64 string and instantly decode it back to human-readable text. Supports Unicode output (emojis, accented characters, CJK scripts). Useful for inspecting tokens, decoding API responses, or reading encoded configuration values.

How to use

  1. Paste your Base64 string into the input panel.
  2. The decoded plain text appears in the output panel instantly.
  3. Click Copy to copy the decoded result to your clipboard.

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Frequently Asked Questions

FAQs about Base64 Decoder

What is Base64 decoding?

Base64 decoding converts a Base64-encoded string back into its original binary or text form. It is the reverse of Base64 encoding.

Why does my decoded output look garbled?

The input may not be valid Base64, or it may represent binary data (like an image) rather than text. Make sure your input is a valid Base64-encoded text string.

Does this tool handle URL-safe Base64?

Standard Base64 uses + and /. URL-safe Base64 replaces these with - and _. This tool decodes standard Base64. If your input uses - and _, replace them with + and / first.

Is there a size limit for Base64 input?

There is no hard limit, but very large inputs may slow down your browser. For best performance keep inputs under a few megabytes.

Can I use this to decode JWT tokens?

Partially. JWT tokens have three Base64Url-encoded parts separated by dots. You can decode each part individually, but this tool does not verify JWT signatures.