What is Base64 encoding and when should I use it?

Base64 encodes binary data into ASCII text using 64 printable characters. Use it when you need to transmit binary data (like images or files) over systems designed to handle text, such as email (MIME) or embedding data in JSON. Base64 is not encryption — it is easily reversible by anyone.

What is a JWT token and how do I decode it?

A JWT (JSON Web Token) is a compact, URL-safe way to represent claims between two parties. It consists of three Base64-encoded parts separated by dots: header, payload, and signature. Decoding a JWT reveals the claims (user ID, expiry, roles, etc.) but does not verify the signature — you need the secret key for verification.

What is the difference between URL encoding and Base64?

URL encoding (percent-encoding) converts characters not allowed in URLs into a % followed by two hex digits, used to safely include special characters in URLs. Base64 converts arbitrary binary data into 64 ASCII characters for text-safe transmission. They serve different purposes and are not interchangeable.

← Back to all tools

⇄ Encoding & Decoding

Base64, Hex, URL encoding, HTML entities, and JWT inspection.

Base64 Encode / Decode

URL-safe Base64 (RFC 4648 §5)

Input

Output

Encoded / decoded result will appear here…

Hex Encode / Decode

Input

Output

Hex encoded / decoded result will appear here…

URL Encode / Decode

Input

Output

URL encoded / decoded result will appear here…

HTML Entities Encode / Decode

Input

Output

HTML encoded / decoded result will appear here…

JWT

JWT Decoder

⚠

This tool decodes JWTs for inspection only — it does not verify the signature. Never trust unverified tokens in production.

JWT Token

Decoded Token

Decoded JWT header, payload and signature will appear here…

❓

Frequently Asked Questions

Is my data sent to a server?

No. All encoding and decoding runs entirely in your browser using JavaScript. Your data is never transmitted to any server and remains completely private on your device.

What is Base64 used for?

Base64 encodes binary data as a text string, making it safe to transmit in text-based contexts. Common uses include encoding email attachments, embedding images as data URLs in HTML/CSS, and encoding binary data in JSON payloads.

What is URL encoding?

URL encoding converts special characters (such as spaces, &, =, and #) into percent-encoded form (e.g., %20 for a space) so they can be safely included in URLs and query strings without breaking the URL structure.