How it works

What is Base64?

Base64 is a binary-to-text encoding scheme that represents binary data in an ASCII string format. It is commonly used when there is a need to encode binary data that needs to be stored and transferred over media that are designed to deal with textual data.

The Decoding Process

When you paste a Base64 string into our converter, the following steps occur entirely within your browser:

• Cleaning: We remove any common prefixes like data:application/pdf;base64,.
• Decoding: The string is converted back into a raw binary stream of bytes.
• Validation: We check the first 5 bytes for the %PDF- signature to ensure it's a valid document.
• Blob Creation: The bytes are wrapped in a Javascript Blob object with the correct MIME type.

Why Client-Side?

Traditional online converters upload your file to their servers, process it, and then let you download it. This creates a security risk for sensitive documents. Our tool uses the File API and Blob API available in modern browsers to do everything locally. Your data is never transmitted over the network.