Base64 Encode / Decode

Convert plain text to Base64 encoding and back. Useful for embedding data in JSON, HTTP headers, or data URIs. Pro: URL-safe Base64 (no +/= chars) and batch mode. Everything runs in your browser — nothing sent to any server.

Frequently Asked Questions

What is Base64 encoding?▼

Base64 is a binary-to-text encoding that converts binary data into a string of ASCII characters using 64 symbols (A-Z, a-z, 0-9, +, /). It's commonly used to embed images in HTML/CSS, transmit binary data in JSON or XML, and encode credentials in HTTP headers.

What is the difference between Base64 and URL-safe Base64?▼

Standard Base64 uses + and / characters which have special meaning in URLs. URL-safe Base64 (RFC 4648) replaces + with - and / with _, making it safe for use in URLs, filenames, and query parameters without percent-encoding.

Does Base64 encoding encrypt data?▼

No. Base64 is encoding, not encryption. Anyone can decode a Base64 string — it provides zero security. It's designed for safe data transport, not data protection. Never use Base64 as a substitute for encryption.

Why does Base64 make data larger?▼

Base64 encodes every 3 bytes of binary data into 4 ASCII characters, resulting in roughly 33% size increase. This overhead is the trade-off for being able to safely transmit binary data through text-only channels like email or JSON.

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