Encoder & Decoder Tools

Free online encoder and decoder tools for developers, security researchers, and data engineers. Base64 encode/decode, URL encoding/decoding, HTML entity encoding, JWT decoder, MD5/SHA-256/SHA-512 hash generators, hex encoder/decoder, Unicode encoder, ASCII encoder, ROT13, Caesar cipher, QR code generator, barcode generator, JavaScript/JSON/XML/CSV/regex string escaping — all running instantly in your browser with zero data sent to any server.

33

Tools

11

Groups

Base Encoding & Decoding URL Encoding & Utilities HTML Encoding & Decoding JWT Tools Hash Generators & Utilities Number Base Converters Text Encoding & Classic Ciphers Data Format Encoders & Converters QR Code Generator & Reader Barcode Generator String Escaping & Unescaping

Base Encoding & Decoding

10 tools

Encode and decode data using Base64, Base32, Base58, and Base85 encoding schemes. Essential for binary-to-text conversion, email attachments, data URIs, API request payloads, and cryptographic data serialization. All conversions run locally in your browser — no data is uploaded.

Base64 Encoder

Encode any text or string to Base64 format instantly

Base64 Decoder

Decode any Base64 string back to plain text instantly

Base64 to Image

Convert a Base64 string to a previewed and downloadable image

Image to Base64

Upload any image and convert it to a Base64 string or data URI

Base32 Encoder

Encode any text to Base32 format using the RFC 4648 alphabet

Base32 Decoder

Decode any Base32 string back to plain text using the RFC 4648 alphabet

Base58 Encoder

Encode any text to Base58 format used in Bitcoin and cryptocurrency systems

Base58 Decoder

Decode any Base58 string back to plain text or hex

Base85 Encoder

Encode any text to Base85 (Ascii85) format for compact binary-to-text encoding

Base85 Decoder

Decode any Base85 or Ascii85 string back to plain text

URL Encoding & Utilities

8 tools

Encode, decode, parse, and build URLs with dedicated tools for percent-encoding (encodeURIComponent), query string parsing, Punycode internationalized domain names, and full URL construction. Fix malformed URLs, inspect query parameters, and prepare strings for safe use in HTTP requests.

URL Encoder

Percent-encode special characters in URLs with three encoding modes

URL Decoder

Decode percent-encoded URLs back to readable text with three decoding modes

URL Parser

Break any URL into its component parts — protocol, host, path, params, and more

URL Builder

Construct any URL from its parts with a live query parameter editor

Query String Encoder

Convert a JSON object or key=value pairs into a URL query string

Query String Decoder

Parse a URL query string into readable key-value pairs, JSON, or line format

Punycode Encoder

Convert internationalized domain names to ASCII-compatible Punycode encoding

Punycode Decoder

Convert ASCII Punycode domain names back to Unicode internationalized form

HTML Encoding & Decoding

4 tools

Encode and decode HTML entities, HTML special characters, and named/numeric entity references. Tools for escaping & < > " ' into & < > " ', decoding entity-encoded content back to readable text, and encoding the full HTML5 named entity set — all running client-side.

HTML Encoder

Encode HTML special characters into safe entities — < > & " '

HTML Decoder

Decode HTML entities back to readable characters — <div> → <div>

HTML Entity Encoder

Convert special characters to named, decimal, or hex HTML entities

HTML Entity Decoder

Decode all HTML entities — named, decimal, and hex — back to characters

JWT Tools

3 tools

Decode, inspect, and verify JSON Web Tokens (JWT) without sending credentials to a server. Visualize header, payload, and signature sections, inspect registered claims (iss, sub, exp, iat, aud), check token expiry, and validate HMAC-SHA256 and HMAC-SHA512 signatures using your secret key.

JWT Decoder

Decode any JWT and inspect header, payload, and signature in colour-coded panels

JWT Encoder

Build and sign a JWT from a JSON payload using HS256, HS384, or HS512

JWT Expiry Checker

Check if a JWT is expired, valid, or not yet active with a live countdown

Hash Generators & Utilities

7 tools

Generate and verify cryptographic hash values entirely in your browser. Supports MD5 (legacy checksums), SHA-1, SHA-256, SHA-384, SHA-512 (via Web Crypto API), SHA-3 and Keccak-256 (Ethereum-compatible), HMAC signatures with configurable secret keys, and a hash identifier that detects algorithm type from an unknown hash string.

MD5 Hash Generator

Generate MD5 hashes from text or files — instant 32-character hex output

SHA-1 Hash Generator

Generate SHA-1 hashes from text or files — 40-character hex output

SHA-256 Hash Generator

Generate secure SHA-256 hashes from text or files — 64-character hex output

SHA-512 Hash Generator

Generate maximum-strength SHA-512 hashes — 128-character hex output

SHA-3 Hash Generator

Generate SHA-3 and Keccak hashes — 224, 256, 384, 512-bit variants + Ethereum Keccak-256

Hash Identifier

Paste any hash and instantly identify its algorithm — MD5, SHA-1, SHA-256, and more

HMAC Generator

Generate HMAC signatures with a secret key — HMAC-SHA256, SHA512, SHA384, SHA1

Number Base Converters

9 tools

Convert numbers between binary (base-2), octal (base-8), decimal (base-10), and hexadecimal (base-16) instantly. Includes a multi-base converter for simultaneous conversion across all bases, bitwise operation tools, and integer format utilities for programming and low-level debugging.

Binary to Decimal

Convert binary numbers to decimal instantly with nibble grouping and bit length

Decimal to Binary

Convert decimal numbers to binary with nibble grouping and cross-base display

Hex to Decimal

Convert hexadecimal numbers to decimal with byte grouping and binary display

Decimal to Hex

Convert decimal numbers to hexadecimal with byte grouping and binary equivalent

Octal to Decimal

Convert octal numbers to decimal with hex and binary equivalents

Decimal to Octal

Convert decimal numbers to octal for Unix permissions and legacy system work

Binary to Hex

Convert binary numbers to hexadecimal with nibble and byte grouping

Hex to Binary

Convert hexadecimal numbers to binary with nibble grouping and decimal display

Number Base Converter

Convert numbers between any base from 2 to 36 with a live all-bases table

Text Encoding & Classic Ciphers

9 tools

Encode and decode text using Unicode escape sequences (\uHHHH, U+HHHH), ASCII decimal/hex/binary/octal codes, hex strings, and classic substitution ciphers — ROT13 encoder/decoder and Caesar cipher encoder/decoder with brute-force all-25-shifts table for unknown shift decoding.

Unicode Encoder

Convert text to Unicode escape sequences — \u0048\u0065\u006C\u006C\u006F

Unicode Decoder

Decode Unicode escape sequences back to readable text — \u0048... → Hello

ASCII Encoder

Convert text to ASCII code numbers — decimal, hex, octal, or binary

ASCII Decoder

Convert ASCII code numbers back to readable text — decimal, hex, octal, or binary

Hex Encoder

Convert text to hexadecimal — plain hex, 0x prefix, \x prefix, or URL percent encoding

Hex Decoder

Convert hex strings back to readable text — handles 0x, \x, % and plain hex

ROT13 Encoder / Decoder

Apply ROT13 substitution cipher — encode and decode spoilers, puzzle text, and obfuscated strings

Caesar Cipher Encoder

Encrypt text with the Caesar cipher — shift letters by any amount from 1 to 25

Caesar Cipher Decoder

Decode Caesar cipher text — reverse any letter shift, with brute-force all-25-shifts table

Data Format Encoders & Converters

3 tools

Compress and decompress data using industry-standard algorithms including Brotli and Gzip, convert between data formats, and encode binary data for safe transmission. All compression and decompression runs entirely in your browser — no files are uploaded to any server.

Brotli Compress

Compress text with Brotli — quality 0–11, Base64 or hex output, real WASM compression in your browser

Gzip Compress

Compress text with gzip — levels 1–9, Base64 or hex output, powered by fflate in your browser

Gzip Decompress

Decompress gzip data — paste Base64 or hex, or upload a .gz file to recover the original text

QR Code Generator & Reader

2 tools

Generate QR codes for URLs, Wi-Fi credentials, email addresses, phone numbers, SMS messages, and plain text — with custom colors, error correction levels (L/M/Q/H), and PNG or SVG export. Decode QR codes from uploaded images or live camera using jsQR, with auto-detection of URL, Wi-Fi, email, and phone content types.

QR Code Generator

Generate QR codes for URLs, text, Wi-Fi, email, phone, and SMS — download as PNG or SVG

QR Code Reader

Scan and decode QR codes from uploaded images or live camera — reads URLs, Wi-Fi, email, and more

Barcode Generator

1 tools

Generate professional barcodes in 12 industry-standard formats: Code 128, Code 39, Code 93, EAN-13, EAN-8, UPC-A, UPC-E, ITF-14, Codabar, MSI/Plessey, Pharmacode, and ITF. Per-format input validation, custom bar colors and height, text label control, and SVG (vector, print-ready) or PNG (2× retina) download.

Barcode Generator

Generate barcodes in 12 formats — Code 128, EAN-13, UPC-A, QR, and more

String Escaping & Unescaping

8 tools

Escape and unescape special characters for safe use in JavaScript strings, JSON values, XML content and attributes, CSV cells, and regular expressions. Includes JS string escape (double/single/template literal/full Unicode modes), JSON escape (RFC 8259 compliant), XML escape (text content and attribute modes), CSV escape (RFC 4180, configurable delimiter), and regex escape with character analysis across 5 flavors: JavaScript, PCRE, Python, and RE2.

JavaScript String Escape

Escape special characters in text for safe use inside JavaScript string literals

javascriptescape

JavaScript String Unescape

Decode JavaScript escape sequences back to readable text — \n, \t, \uHHHH, and more

javascriptdecode

JSON String Escape

Escape text for safe use inside JSON string values — RFC 8259 compliant

JSON String Unescape

Decode JSON escape sequences back to readable text — \n, \t, \uHHHH, and more

XML Escape

Escape special characters for safe use in XML and HTML — &, <, >, ", and '

XML Unescape

Decode XML/HTML entities back to characters — &lt; → <, &amp; → &, and more

CSV Escape

Escape text for safe use in CSV cells — handles commas, quotes, newlines per RFC 4180

Regex Escape

Escape special regex metacharacters so a string is matched literally — . * + ? ^ $ ( ) [ ] { } | \