Base64
Base64 (RFC 4648) encodes every 3 bytes into 4 ASCII characters from A–Z a–z 0–9 + /. Padding with = keeps the length a multiple of 4. Used in MIME email, data URIs, JWT, Kubernetes secrets and more.
Online Encoder / Decoder — Base64, Hex, Base32, URL
Encode and decode Base64, Base64 URL, Base32 (RFC 4648), Hex, URL percent, HTML entities, ROT13, Binary и ASCII decimal. Everything runs locally in your browser — no strings are ever uploaded.
(13 chars / 13 bytes)
Keyboard: Ctrl/⌘ + Enter — encode, with Shift — decode.
Supported formats
Base64 URL
URL-safe variant: + → -, / → _, no padding. Used in JWT, OAuth and anywhere a token must survive being embedded in a URL or filename.
Base32 (RFC 4648)
Uses A–Z 2–7. Case-insensitive, so it is preferred for TOTP secrets and anywhere a human has to type the value.
Hex
Each byte is represented by two hexadecimal characters. The most common representation for hashes, MACs and raw binary data in a readable form.
URL percent-encoding
Escapes reserved characters as %XX. Required for query parameters, path segments and form data (encodeURIComponent / decodeURIComponent).
HTML entities
Escapes & < > " ' to prevent XSS and to safely render user-provided content inside HTML. Supports named and numeric entities.
ROT13
A trivial Caesar shift by 13 — its own inverse. Useful for hiding spoilers and puzzles, not for security.
Binary (base 2)
Each byte as 8 bits, space-separated. Handy for teaching, bitwise debugging and low-level protocols.
ASCII decimal
Each byte as a decimal code point (0–255). Useful for legacy protocols and character set debugging.
Frequently asked questions
What is Base64?
Base64 is a binary-to-text encoding that represents arbitrary bytes using 64 printable ASCII characters (A–Z, a–z, 0–9, +, /). It is used to embed binary data in JSON, XML, email (MIME) and data URIs.
What is the difference between Base64 and Base64 URL?
Base64 URL replaces '+' with '-' and '/' with '_' and omits padding '='. It is safe to use in URLs and filenames, e.g. in JWTs.
How do I decode a hex string?
Paste the hex string into the input, select 'Hex' and press Decode. Every two hex characters represent one byte.
Is my data uploaded anywhere?
No. Encoding and decoding happen entirely in your browser.
Related tools
All operations run locally in your browser.