What is Base64 encoding?

Base64 converts binary or text data into an ASCII string using 64 characters (A–Z, a–z, 0–9, +, /).

What does strict mode do in decoding?

Strict mode validates the input and rejects characters outside the Base64 alphabet and incorrect padding.

No. This tool does not store any data on the server.

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Base64 Encoder & Decoder

Convert text to Base64 or decode Base64 back to text. Copy or download results instantly. No storage.

About Base64

Base64 encoding transforms data into a safe ASCII representation, ideal for embedding small files in HTML/CSS as data: URIs, sending attachments via email (MIME), or transporting binary through text-based protocols. Decoding reverts the string to its original form. Enable Strict decode to validate padding and characters.