Base64 Encoder / Decoder

Base64 is an encoding scheme that converts binary data into ASCII text using 64 printable characters. It is used when binary data needs to be transmitted over systems designed for text — such as embedding images in HTML/CSS, encoding email attachments (MIME), storing binary data in JSON, and API authentication tokens.

Type or paste your text into the input field and select Encode. The Base64-encoded string appears instantly in the output. Click Copy to clipboard to use it in your code, API request, or email system.

Paste the Base64-encoded string into the input field and select Decode. The original text or binary data is restored in the output area. If the Base64 represents a file (like an image), you can view and download it directly.

Standard Base64 uses '+' and '/' characters which have special meaning in URLs and can cause issues. URL-safe Base64 replaces '+' with '-' and '/' with '_', making the encoded string safe for use in URLs, query parameters, and filenames without percent-encoding. Use URL-safe mode for tokens in web applications.

Yes. Switch to File mode, upload your image (or any file), and the tool generates a Base64 Data URI. This is useful for embedding images directly in HTML or CSS without a separate HTTP request, reducing the number of network requests in web applications.

Completely safe. All encoding and decoding happens locally in your browser using JavaScript's `btoa()` and `atob()` functions for text, and FileReader API for files. Nothing is transmitted to any server. Your data remains entirely on your device.

Yes. Paste a Base64 data URI (starting with 'data:image/png;base64,...') into the input and select Decode to view and download the image. This is useful for debugging encoded images in API responses or HTML source code.

Base64 encodes every 3 bytes of binary data into 4 ASCII characters, adding approximately 33% to the original size. This is an expected trade-off when converting binary data for text-compatible transmission. The increase is predictable and can be accounted for in your application logic.

Yes. The tool is fully mobile-responsive and works in any modern browser. You can encode and decode text or small files directly on your phone without any additional apps.

Yes, 100% free. No sign-up, no usage limits, and no file size restrictions for text. File encoding is limited to reasonable browser memory limits. Use it as often as needed at no cost.