Developer Tools Box
Encoding15
JSON Formatter
Free online JSON formatter and validator. Format, beautify, validate, compress JSON with syntax highlighting and detailed error messages for developers
Base64 Encoder / Decoder
Free online Base64 encode/decode tool with text and image support, real-time preview
URL Encoder / Decoder
Free online URL encoder/decoder tool, supports encode and decode with one-click copy
HTML Entities Encoder / Decoder
HTML special character entity encoder/decoder with escape and unescape support
JWT Decoder
Free online JWT decoder tool, parse JSON Web Token and inspect Header and Payload
HTML Encoder / Decoder
Free online HTML encoder & decoder tool. Instantly encode or decode HTML entities, special characters, and tags. No ads, no upload, ready to use.
Base32 Encoder / Decoder
Free Base32 decode & encode tool online. Convert text and byte data instantly with this no-ad, privacy-first Base32 encoder/decoder.
Unicode Converter
Unicode converter tool, supports Unicode to Chinese and Chinese to Unicode with emoji support
Image to Base64 Converter
Online image to Base64 converter supporting PNG, JPG, GIF, SVG and more formats
Base85 Encoder / Decoder
Free online Base85 encode/decode tool, more efficient encoding scheme than Base64
URL Query String Builder
Visual URL query parameter builder, add/edit/delete parameters, one-click URL construction
Gray Code Converter
Free online Gray code to binary converter. Encode and decode 32-bit Gray code for digital communications and error correction
ASCII Code Table
Free online ASCII code table lookup tool. Complete 128-character ASCII table with decimal, hex, binary, and character display with search
Morse Code Converter
Free online Morse code encoder/decoder. Convert text to Morse code and vice versa with audio playback
URL Decoder
Free online URL decoder tool. Decode percent-encoded URLs back to readable format. Supports Chinese characters and special characters. Ideal for API debugging
Text Processing17
Text Diff Checker
Online text diff checker using Google diff-match-patch algorithm, accurately compare text differences
Word Counter
Free online word counter tool, count characters, words, lines, paragraphs with CJK support
Markdown Preview
Online Markdown real-time preview editor with syntax highlighting and export support
Case Converter
English case converter supporting UPPERCASE, lowercase, Title Case, and toggle case
Whitespace Remover
Remove whitespace, newlines, tabs from text with customizable removal options
Text Deduplicator
Online text deduplicator to remove duplicate lines, preserving order or sorting output
Text Replacer
Online text batch replacement tool with regex support and multiple replacement rules
Text Line Tools
Text line processing toolkit supporting sort, reverse, filter, merge, and split operations
Regex Tester
Online regex tester with real-time matching, highlighting, and capture group extraction
Lorem Ipsum Generator
Lorem Ipsum dummy text generator with customizable paragraphs and word count
CSS Formatter / Minifier
Online CSS formatter, beautifier, and minifier with multiple formatting styles
HTML / JS / CSS Minifier
Online HTML, JavaScript, CSS code minifier to remove whitespace and comments, reducing file size
XML Formatter
Free online XML formatter, beautifier and minifier with syntax highlighting and node collapsing
SQL Formatter
Free online SQL formatter, beautifier and minifier supporting SELECT, INSERT, UPDATE, DELETE and more
Discord Markdown Preview
Free online Discord Markdown preview tool with live rendering. Supports code block color tricks, blockquotes, lists, and more
Slug Generator
Free online slug generator. Convert any text into URL-friendly slug format with real-time conversion
.env File Formatter / Validator
Free online .env file formatter and validator. Format, sort, validate env vars, detect duplicates with alignment
Data Conversion42
Epoch & Timestamp Converter
Convert between Unix timestamps and human-readable date/time formats
Base Converter
Binary, octal, decimal, hexadecimal converter with arbitrary base conversion
CSV to JSON Converter
Convert between CSV and JSON formats with custom delimiters and header processing
JSON to Markdown Table
Convert JSON data to Markdown table format with array object support and alignment
Markdown Table to HTML
Convert Markdown table syntax to HTML table code with styling and formatting
YAML to JSON Converter
Convert between YAML and JSON formats using js-yaml library with complex syntax support
Color Converter
Free online hex to RGB color converter with real-time preview. Convert between HEX, RGB, HSL color formats instantly
JSON to TypeScript
Auto-generate TypeScript interface definitions from JSON data with optional and readonly props
URL Parser
Detailed URL parser tool that extracts protocol, domain, port, path, query parameters, hash
JSON Compare
Online JSON comparison tool, deep diff two JSON objects with highlighted additions and deletions
CSV Viewer
CSV data table viewer with search, sort, filter, and export to JSON support
IP Subnet Calculator
IP address subnet calculator for network address, broadcast, host range, subnet mask
JSON to XML Converter
Convert between JSON and XML formats with attribute parsing and array handling
CSS Gradient Generator
Online CSS gradient generator with multi-color stops, angle adjustment, real-time preview
Cron Expression Parser
Cron expression parser with 5-field format support and next execution time calculation
Snowflake ID Decoder
Free online Twitter & Discord Snowflake ID decoder. Extract timestamp, worker ID, and sequence number from any Snowflake ID
UUID Validator
Free online UUID validator and version checker. Validate UUID format, detect UUID version and variant automatically
Number to Words Converter
Free online Chinese number to words converter for financial amounts, invoices and accounting
Color Hex Code Lookup
Free online color hex code lookup tool. Search color names and get HEX, RGB, HSL values. 140+ common colors with live preview
Excel to JSON Converter
Free online Excel to JSON converter tool. Upload .xlsx files and convert to JSON format instantly. Supports multiple worksheets, client-side processing
Phone Number to Words Converter
Free online phone number to words converter. Turn numbers into letter combinations like 1-800-FLOWERS. Supports custom word lists
JSON to Excel Converter
Free online JSON to Excel converter tool. Transform JSON data into .xlsx spreadsheets instantly. Supports arrays, nested objects, and custom column mapping. Client-side only, no upload
Binary Translator
Free online binary translator tool. Convert text to binary code (0101) and binary back to text with one click
JSONL Formatter / Converter
Free online JSONL formatter and converter tool. Convert between JSONL and JSON, validate each line, and beautify JSONL data. No upload, client-side only.
Barcode Generator
Free online barcode generator supporting Code 128, EAN-13, UPC-A, Code 39, ISBN. Bulk generate barcodes and download as PNG or SVG
Image Compressor
Free online image compressor with quality slider, target file size presets (50KB/20KB), and resize dimensions. All processing in browser, no upload
Unit Converter
Free online unit converter for length, weight, temperature, area, volume, speed and more. Real-time conversion, swap units, one-click copy. Essential daily tool for everyone.
World Clock
Free online world clock and time zone converter. View current time in major cities worldwide, convert time between time zones instantly. Essential for remote work and global collaboration.
Image to PDF Converter
Free online image to PDF converter. Convert JPG, PNG, GIF, WEBP images to PDF with custom page size, orientation, and margins. Merge multiple images into one PDF. All in your browser, no upload required.
IP Geolocation Lookup
Free online IP geolocation lookup tool. Find country, region, city, ISP, coordinates and more for any IP address
DNS Lookup Tool
Free online DNS lookup tool. Query A, AAAA, CNAME, MX, NS, TXT, SOA records via DNS over HTTPS
Image to Text (OCR)
Free online OCR tool using Tesseract.js to extract text from images. Multi-language recognition, all in your browser
WebP Converter
Free online WebP to PNG/JPG converter and vice versa. Quality control, all Canvas-based browser processing
Image Resizer
Free online image resizer. Custom width/height with aspect ratio lock and preset sizes. Pure browser-side Canvas processing
Merge PDF
Free online PDF merge tool. Combine multiple PDF files into one with drag-and-drop reordering. All in your browser
Split PDF
Free online PDF split tool. Extract page ranges or split every page into separate PDFs. All in your browser
RGB to HEX Converter
Free online RGB to HEX color converter. Input RGB values and get hex color code instantly with live color preview and one-click copy
HEX to RGB Converter
Free online HEX to RGB color converter. Enter hex color code and convert to RGB values instantly with live color preview and one-click copy
Hex to Binary Converter
Free online hex to binary converter. Quickly convert hexadecimal numbers to binary format. Ideal for programming and digital logic
Binary to Hex Converter
Free online binary to hex converter. Quickly convert binary numbers to hexadecimal format. Ideal for programming and digital logic
Decimal to Binary Converter
Free online decimal to binary converter. Quickly convert decimal numbers to binary format. Perfect for CS101 and programming fundamentals
Binary to Decimal Converter
Free online binary to decimal converter. Quickly convert binary numbers to decimal format. Perfect for CS101 and programming fundamentals
Security16
HMAC Signer
HMAC signature generator supporting SHA-1, SHA-256, SHA-512 hash algorithms with secret key signing
Hash Generator
Online hash generator supporting MD5, SHA-1, SHA-256, SHA-512 and more algorithms
Password Generator
Secure random password generator with customizable length and character types
Hash Checker
File hash verification tool for integrity checking with MD5, SHA1, SHA256 comparison
JSON Schema Validator
Online JSON Schema validator to validate JSON data against schema specifications
AES Encrypt / Decrypt
Free AES-256 encrypt & decrypt online tool supporting AES-128, AES-192, and AES-256. No ads, no upload, instant in-browser symmetric encryption.
Password Strength Tester
Free online password strength tester. Analyze password security, estimate crack time, check against common passwords, visual strength indicator
Bcrypt Hash Generator
Free online bcrypt hash generator and hashing tool. Generate, verify and compare bcrypt passwords and hashes with configurable salt rounds (4-12)
Argon2 Hash Generator
Free online Argon2 hash generator and verifier. Supports argon2i, argon2d, and argon2id modes with configurable time cost, memory cost, and parallelism. The award-winning password hashing algorithm for modern security
SM3 Hash Generator
Free online SM3 hash generator - Chinese National Standard hash algorithm (GB/T 32905-2016). Generate 256-bit hash values for data integrity and digital signatures. Pure browser-side processing.
SM4 Encrypt / Decrypt
Free online SM4 encrypt/decrypt tool - Chinese National Standard block cipher (GB/T 32907-2016). Supports ECB and CBC modes. Pure browser-side processing, no data upload.
JWT Generator
Free online JWT generator supporting HS256, HS384, HS512 algorithms. Custom header and payload with secret key signing
JWT Key Generator
Free online RSA and EC key pair generator for JWT. Supports RS256/RS384/RS512 and ES256/ES384/ES512 with JWK and PEM export
HTTP Security Headers Checker
Free online HTTP security headers checker. Analyze CSP, HSTS, X-Frame-Options, X-Content-Type-Options and more
SSL Certificate Checker
Free online SSL certificate checker tool. Check HTTPS reachability and decode PEM certificate information
AES Key Generator
Free online AES key generator. Generate secure AES-128/192/256 bit keys in HEX and Base64 format. Uses browser crypto API for secure key generation
ID Generator8
Random UUID Generator Online
Online UUID generator supporting v1 and v4 versions with batch generation
NanoID Generator
Free online NanoID generator — create secure, compact unique identifiers. Shorter and faster than UUID with customizable ID length (8-64 chars) and charset. Perfect for database keys, URL short links, session tokens, and distributed systems
Random String Generator
Customizable random string generator with letters, numbers, special characters support
ULID Generator
Online ULID generator — create timestamp-sortable unique identifiers. 26-char Crockford Base32 format: 10 chars timestamp (ms precision) + 16 chars secure random
CUID / CUID2 Generator
Online CUID2-style unique ID generator — compact, collision-resistant identifiers with lowercase alphanumeric characters. Designed for horizontal scaling in distributed systems
UUID v7 Generator
Online UUID v7 generator (RFC 9562) — time-ordered unique identifiers with 48-bit Unix ms timestamp prefix. Sortable and drop-in compatible with existing UUID formats
Snowflake ID Generator
Twitter & Discord Snowflake ID generator — 64-bit distributed unique IDs used by Twitter and Discord with configurable worker/node ID. Time-ordered, monotonically increasing, perfect for microservices
API Token Generator
Online API key generator with customizable prefix and multiple encoding formats (Hex, Base64URL, Base62). Uses browser-native crypto — your keys never leave your machine
QR Code2
QR Code Generator
Free online QR code generator with custom content, size, error correction, and PNG download
Custom QR Code Generator
Custom style QR code generator with color and size customization
AI Tools3
Old Photo Restore
AI old photo restoration using GFPGAN model — fix blur, scratches, and recover face details
LLM Token Counter
Free online LLM token counter. Estimate token usage across AI models (GPT, Claude, Llama). Character and word count included
Ollama Model Reference
Ollama open-source model reference sheet. Compare Llama, Mistral, Phi, Qwen models by parameters, use cases, and hardware requirements