Base64 Encoder & Decoder
Encode text to Base64 or decode Base64 back to plain text — instantly. Supports URL-safe encoding, JWT token decoding, and HTTP Basic Auth generation. Free. No sign-up.
HTTP Basic Auth Generator
How it works
- 1Paste your text or Base64
Enter plain text to encode, or paste a Base64 string to decode. The tool auto-detects Base64 on paste.
- 2Choose direction
Click “Encode to Base64” or “Decode from Base64”. Toggle URL-safe mode if needed.
- 3Copy the result
Click Copy on the output panel. Use the Basic Auth or JWT helpers below for specialised workflows.
What Is Base64 and When Do You Need It?
Base64 is one of the most widely used encoding schemes on the web. Every time you embed an image as a data URI in CSS, pass binary data through a JSON API, or authenticate with a server using HTTP Basic Auth, Base64 is doing the heavy lifting behind the scenes. The encoding converts arbitrary binary data into a safe subset of 64 ASCII characters, ensuring it survives transport through systems that only handle text.
Developers encounter Base64 constantly. Data URIs in HTML and CSS use Base64 to inline small images and fonts, eliminating extra HTTP requests. JSON Web Tokens (JWTs) encode their header and payload segments as Base64url strings, making them compact enough to fit in HTTP headers and URL parameters. HTTP Basic Authentication concatenates a username and password with a colon separator, Base64-encodes the result, and sends it in the Authorization header.
The Layman SEO Base64 tool handles all these workflows in one place. Paste a JWT and the tool automatically detects its three-part structure and shows you the decoded header and payload as formatted JSON. Enter a username and password in the Basic Auth helper and get a ready-to-use Authorization header. Toggle URL-safe mode to produce output that replaces + with - and / with _, following the RFC 4648 standard used by JWTs and many modern APIs.
Everything runs in your browser using native btoa, atob, TextEncoder, and TextDecoder APIs. No data is sent to any server, making the tool safe for encoding sensitive credentials and tokens.