Base64 Decoder

Decode Base64 strings back to plain text instantly. Supports UTF-8, ASCII, Unicode, emoji, and corrupted string detection. 100% client-side.

Last Updated: August 2026
100% Client-Side — Your data never leaves your device

Why this tool is safe

Your data never leaves your device — everything runs in your browser.

No server uploads. Other tools send your files to their servers. Ours don't.
Zero tracking of content. We never see, store, or log anything you convert.
Works offline. Once loaded, the tool works without an internet connection.
No account required. Instantly use all tools completely free without signing up.

What is Base64 Decoding?

Base64 decoding is the reverse process of Base64 encoding. It takes a Base64-encoded string and translates it back into its original plain text or binary format.

Our Base64 Decoder instantly processes your encoded string and outputs the readable text. It automatically handles standard padding characters ('=') and ignores any invalid whitespace or line breaks in your input.

Why do I need this?

Often, you'll encounter Base64 encoded data in web development, API responses, or system logs. To read and understand this data, you must decode it first.

  • Extracting information from JSON Web Tokens (JWT).
  • Reading encoded email bodies or attachments.
  • Debugging API requests that transmit data in Base64.
  • Analyzing configuration files or Kubernetes secrets.

Frequently Asked Questions

Search below or browse through our most commonly asked questions.

Paste your Base64 encoded string into the input area. The tool will immediately decode it back to readable text and display character count and byte size.
The decoder will display an error message explaining the issue. You can also use our Base64 Repair or Normalizer tools to fix malformed padding or invalid characters.
Yes. The decoding process runs entirely in your browser. No strings are ever transmitted over the network or stored.

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