Free Online Encoding & Decoding Tools

High-performance developer utilities to encode, decode, hash, and inspect web payloads. Fast, private, and 100% client-side with zero server latency.

Base64 Encoder & Decoder

Convert text and files to and from Base64 format for safe transmission and data URI embedding.

Open Base64 Tool

URL Encoder & Decoder

Percent-encode query parameters and decode URL strings to ensure RFC 3986 compliance.

Open URL Tool

HTML Entity Encoder & Decoder

Convert characters to safe HTML entities (&, <, >) to protect against Cross-Site Scripting (XSS).

Open HTML Tool

JWT Encoder & Decoder

Decode, inspect claims, check expiration, and sign/verify HMAC-SHA256 JSON Web Tokens in the browser.

Open JWT Tool

Cryptographic Hash Generator

Generate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 cryptographic hashes in Hex or Base64 format.

Open Hash Tool

Data Size & Bytes Converter

Convert data units between Bytes, KB, MB, GB, TB, and PB across binary and SI standards.

Open Bytes Tool

Understanding Web Encodings & Security Standards

Web protocols and internet services frequently handle data across environments with restricted character sets. Using the appropriate encoding technique ensures that information arrives without corruption, while preventing critical security vulnerabilities like Cross-Site Scripting (XSS) and injection attacks:

🌐 URL Percent-Encoding (RFC 3986)

Replaces non-ASCII or reserved characters (like spaces, question marks, and ampersands) with a percent sign followed by hexadecimal digits (e.g., space becomes %20). Essential for query string parameters.

🛡️ HTML Entity Encoding

Converts special HTML markup characters (<, >, &, ", ') into predefined entities (like &lt;). This prevents browsers from executing user-supplied strings as code.

📦 Base64 Binary-to-Text Encoding

Translates 8-bit binary payloads into 6-bit ASCII representations. Commonly used in HTTP Basic Auth headers, MIME emails, and data URI schemes (data:image/png;base64,...).

🗝️ JWT (JSON Web Tokens) & Hashes

JWTs format authorization claims into Base64URL-encoded JSON segments with cryptographic HMAC or RSA signatures. Hashes (SHA-256, MD5) provide one-way checksums for integrity verification.

Frequently Asked Questions: Encoding & Decoding Tools

No. Encoding (like Base64, URL encoding, or HTML escaping) transforms data into a different format for safe transport and can be reversed by anyone without a key. Encryption secures data using a cryptographic key so that only authorized recipients can read it.

Yes. All conversions, JWT validations, and hash generations run 100% locally inside your web browser using modern Web Crypto APIs. No text, tokens, or hashes are sent to or stored on any server.

Our Hash Generator supports MD5, SHA-1, SHA-256, SHA-384, and SHA-512 with outputs available in both standard hexadecimal and Base64 format.