Base64 Encoder / Decoder
Encode text into Base64 or decode Base64 back to readable text. Full UTF-8 support for emoji, Chinese, and any Unicode input. Everything runs in your browser — your data never leaves your device.
About Base64 Encoding
Base64 is a binary-to-text encoding scheme that represents arbitrary binary data using a 64-character alphabet: A-Z, a-z, 0-9, +, and /. It was originally designed so binary content could be transmitted through protocols that only reliably handle ASCII text — email (MIME), HTTP headers, JSON payloads, XML, and data URIs.
Common use cases
- Embedding small images inside CSS or HTML using
data:URIs - Encoding credentials for HTTP Basic Authentication headers
- Safely storing binary data in JSON or database text fields
- Sending attachments through email via MIME
- Representing cryptographic tokens, JWTs, and API keys
Standard vs. URL-safe variant
Standard Base64 uses + and /, which have special meaning in URLs and filenames. The URL-safe variant (RFC 4648 §5) replaces them with - and _, and typically omits the = padding. Toggle the option above when working with URLs, JWT tokens, or file names.
Not encryption
Base64 is fully reversible with no secret key. Anyone can decode a Base64 string back to its original content. Never use Base64 to protect passwords, API secrets, or personal data — use proper cryptographic hashing or encryption instead.
Frequently Asked Questions
= padding at the end?= characters are added to pad the output to a multiple of 4.