Free Online Base64 Encoder/Decoder

Base64 encoding is used to safely transmit binary data over text-based systems. Common uses include email attachments (MIME encoding), embedding images in HTML/CSS using Data URIs, encoding API payloads, storing binary data in JSON/XML, and encoding authentication credentials.

No, Base64 is not encryption and provides no security. Anyone can decode Base64 data instantly. It is purely an encoding scheme for data representation, not protection. For security, use proper encryption like AES before optionally Base64-encoding the result.

Base64 uses 64 characters to represent data, meaning each character carries 6 bits of information. Since input bytes are 8 bits each, the encoding process converts 3 bytes (24 bits) into 4 characters. This 4/3 ratio results in roughly 33% size increase.

Standard Base64 uses +, /, and = characters which have special meanings in URLs. URL-safe Base64 replaces + with -, / with _, and often removes = padding. This makes encoded data safe to include in URLs and filenames.

Yes, you can paste the content of text files directly. For binary files, you would need to first read them as binary data. This browser-based tool works best with text content and small data payloads.

No, all encoding and decoding happens entirely in your browser using JavaScript. Your data never leaves your device, ensuring complete privacy for sensitive information.