What is Base64 encoding?

Base64 is an encoding scheme that converts binary data into a string of ASCII characters using 64 printable characters (A-Z, a-z, 0-9, +, /). It is used to safely transmit binary data over systems that only support text — such as email, JSON payloads, and HTML data URIs.

Base64 is commonly used for: embedding images in HTML or CSS as data URIs, encoding binary attachments in emails (MIME), storing binary data in JSON APIs, encoding credentials in HTTP Basic Authentication headers, and transmitting cryptographic keys and certificates.

Base64 Encoder / Decoder

Enter text to encode it to Base64, or paste a Base64 string to decode it back to plain text. Useful for web development, API integration, and data transmission tasks.

Base64 Converter

Common Base64 Use Cases

Data URIs — embed small images or fonts directly in CSS or HTML: url('data:image/png;base64,...')
Email attachments — MIME encoding converts binary attachments to Base64 for transport through email protocols
HTTP Basic Authentication — credentials are sent as Authorization: Basic base64(username:password)
API payloads — transmit binary data (images, files) inside JSON fields which only support strings
JWT tokens — JSON Web Tokens use Base64URL (a URL-safe variant) to encode header and payload sections

Related Tools

URL Encoder/Decoder

Percent-encode URL strings

Binary Converter

Convert text to binary

MD5 Generator

Generate MD5 hash strings

JSON Validator

Validate and format JSON