Base64 Decoder – Free, Fast & Private

Decode any Base64 string back to its original text, JSON, or image — instantly, securely, and offline. All decoding happens directly in your browser, never uploaded to any server.

Upload or Paste Base64

or select a file

Drag & Drop Base64 text files here or click to add

Your file stays on your device — never uploaded anywhere.

Decoded Output

Decoded output will appear here.
Need to encode Base64 instead?

Why Use Tools Oasis Base64 Decoder?

Tools Oasis gives you a fast and secure Base64 decoding experience. Whether you’re debugging API data, extracting images, or decoding JSON, it all happens privately in your browser.

  • 100% Private: No data leaves your device.
  • Instant Results: Paste Base64 or drop files and see decoded results instantly.
  • Image Preview: Automatically detects and shows decoded images inline.
  • One-Click Download: Save decoded content as a file.
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Related Tools You Might Need

Base64 Encoder → URL Encoder/Decoder → Hash Generator → JWT Decoder →

Frequently Asked Questions

How do I decode a Base64 string?

Simply paste your Base64-encoded string into the input field and click "Decode Base64." The tool will instantly convert it back to readable text or display the decoded image. You can also drag and drop a .txt or .b64 file containing Base64 data.

Is Base64 decoding secure?

Yes, when using Tools Oasis. All decoding happens locally in your browser using JavaScript — no data is uploaded, stored, or shared with any server. However, keep in mind that Base64 itself is not encryption; it is an encoding format that anyone can decode.

Can I decode Base64-encoded images?

Yes. The tool automatically detects Base64-encoded images (JPG, PNG, GIF, WebP) and displays a live preview directly on the page. You can then download the decoded image file with one click.

What formats are supported for decoding?

You can decode Base64 representing plain text, JSON, HTML, XML, and image formats including JPG, PNG, GIF, and WebP. The tool supports both raw Base64 strings and full data URIs (e.g., data:image/png;base64,...).

Is this Base64 decoder free to use?

Yes. Tools Oasis Base64 Decoder is completely free with no signup, no payment, and no usage limits. All processing runs locally in your browser for maximum privacy and speed.