Encode and decode Base64
Turn text or files into Base64 and back, with URL-safe output when you need it. Everything happens in your browser as you type.
- Runs in your browser
- Nothing is uploaded
- Free, no sign-up
Data URLs
Embed images, fonts, and files directly in HTML and CSS using data URLs.
API authentication
Basic authentication headers and JWT tokens use Base64 encoding.
Binary data transfer
Safely move binary data through text-only formats like JSON and XML.
About Base64 encoding
Base64 is a binary-to-text encoding scheme that converts binary data into ASCII text. It's widely used in web development for embedding images, transmitting data over text-based protocols, and encoding authentication credentials.
How Base64 works
Base64 uses 64 ASCII characters (A–Z, a–z, 0–9, + and /) to represent binary data. Every 3 bytes of input become 4 Base64 characters, so the output is about 33% larger than the input.
Common uses
- Data URLs: embed images and files directly in HTML and CSS.
- Email attachments: MIME email encoding uses Base64.
- API authentication: Basic Auth headers are Base64-encoded.
- JWT tokens: JSON Web Tokens use URL-safe Base64.
- Binary data in JSON: transfer files through REST APIs.
- Obfuscation: simple encoding (not encryption!) of text.
URL-safe Base64
Standard Base64 uses + and /, which can cause problems in URLs. URL-safe Base64 replaces them with - and _ and drops the = padding, so the result is safe in query parameters and file names.
Features
- Encode text to Base64 instantly, and decode it back
- Upload and encode files
- Download encoded or decoded results
- URL-safe encoding and decoding
- Real-time size calculations
- 100% client-side processing
Working with API responses? ScrapingBot scrapes any page with built-in proxy rotation and JavaScript rendering, and returns screenshots as Base64. See the API docs.