Developer Tools
Free online tools for developers. All processing happens in your browser. Nothing is sent to any server.
Base64 File Converter
Convert files to Base64 data URIs and decode Base64 back to editable files. Supports images, PDFs, documents, and more.
Text Diff
Compare two texts line by line with color-coded diff highlighting. Find added, removed, and unchanged lines.
Bcrypt Hash & Verify
Generate bcrypt password hashes and verify passwords against existing bcrypt hashes. Adjustable cost factor (rounds).
AES Encryption
Encrypt and decrypt text using AES-CBC and AES-GCM. Supports 128/192/256-bit keys. All client-side using Web Crypto API.
User-Agent Parser
Parse any User-Agent string to identify browser, OS, device, and engine. Also shows your current browser's UA string.
Chmod Calculator
Calculate Linux file permissions visually. Toggle Read/Write/Execute for Owner, Group, and Others. See octal and symbolic notation.
IP Address Tools
Calculate subnet ranges, CIDR notation, and convert between IP formats. Supports IPv4 subnet calculation.
JSONPath Tester
Test JSONPath expressions against JSON data in real-time. Supports dot/bracket notation, array slicing, filter expressions, and recursive descent.
Lorem Ipsum Generator
Generate Lorem Ipsum placeholder text. Configurable paragraphs, sentences, and words. Ideal for design mockups and content placeholders.
Signature Verification
Verify payment and API signatures. Compare computed HMAC/RSA signatures with received values. Supports MD5, SHA1, SHA256, SHA512, RSA-SHA256.
Webhook Receiver
Create a temporary webhook endpoint to receive and inspect payment callbacks. Real-time event display with headers and body inspection.
Payment API Debugger
Complete payment API debugging workflow. Construct, sign, send, and inspect requests. Supports Alipay, WeChat Pay, and Stripe.
HTTP Status Codes
Complete reference of all HTTP status codes. Browse 1xx–5xx codes with descriptions. Search by code or keyword.
ULID Generator
Generate ULIDs (Universally Unique Lexicographically Sortable Identifiers). Time-ordered, URL-safe, 26 chars. Batch generation supported.
JSON to Code
Convert JSON to typed code in 8 languages. TypeScript interfaces, Go structs, Python dataclasses, Java classes, Rust structs, and more.
JWT Decoder
Decode and inspect JWT tokens. View header and payload claims in a readable JSON tree. All client-side.
JSON Diff
Compare two JSON objects side by side. Find added, removed, and changed properties with visual diff highlighting.
JSON ↔ CSV
Convert between JSON arrays and CSV format. Also supports JSONL (JSON Lines) format. All client-side processing.
JSON ↔ YAML
Convert between JSON and YAML formats. Perfect for config files, API specs, and CI/CD pipelines.
SQL Formatter
Format and beautify SQL queries. Supports MySQL, PostgreSQL, SQLite, and more dialects.
Case Converter
Convert text between camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, and more naming conventions. Real-time conversion.
HTML Entities
Encode or decode HTML entities. Convert special characters to their HTML entity equivalents and back. All client-side.
XML Formatter
Format and beautify XML documents. Indent, validate, and compress XML. All client-side.
Base64 Encode / Decode
Encode text to Base64, decode Base64 back to text, or convert files to Base64 data URIs. All processing happens in your browser.
Hash Generator
Generate MD5, SHA1, SHA256, SHA384, and SHA512 hashes for any text. All processing happens in your browser using the Web Crypto API.
Timestamp Converter
Convert between Unix timestamps and human-readable dates. Supports seconds, milliseconds, and timezone offset.
URL Encode / Decode
Encode strings for safe URL usage or decode percent-encoded URLs. Choose between encodeURIComponent and encodeURI modes.
UUID Generator
Generate UUID v4 (random) and v7 (time-ordered) UUIDs. Supports batch generation up to 100 UUIDs at once.
Password Generator
Create strong, random passwords with full control over length and character types. Includes a visual strength meter.
QR Code Generator
Generate QR codes from any text, URL, or data. Download as PNG. All processing happens in your browser. Nothing is sent to any server.
Currency Converter
Convert between 50+ currencies with real-time exchange rates. Useful for cross-border payments, international transactions, and multi-currency financial calculations.
Acquiring Margin Calculator
Calculate processing fee revenue, channel cost, FX margin, total gross margin, and export merchant quote assumptions.
HMAC Signature Generator
Generate HMAC (Hash-based Message Authentication Code) signatures. Essential for payment gateway integration, API authentication, and webhook signature verification.
Word Counter
Count characters (with and without spaces), words, lines, sentences, and paragraphs in real-time. All processing happens in your browser.
Color Converter
Convert between HEX, RGB, HSL, HSV, and CMYK color formats. Real-time preview swatch. All processing happens client-side.
Regex Tester
Test regular expressions in real-time. Enter a regex pattern and test text to see matches highlighted with detailed match information.
Payment Webhook Simulator
Simulate payment callbacks from Alipay, WeChat Pay, and Stripe. Fill in parameters, generate a signed POST request, and send it to your webhook URL for testing.
RSA Key Pair Generator
Generate RSA public/private key pairs (2048 or 4096 bits) directly in your browser. Export keys in PEM format.
Cron Expression Generator
Build cron expressions visually using dropdown selectors. See the next 10 scheduled execution times in real-time. Includes common presets.
frp Tunnel Config Generator
Generate frpc.ini files for HTTP and TCP tunnels. Copy the config or download it as a file.
Markdown Preview
Write Markdown with real-time HTML preview. Supports GitHub Flavored Markdown (GFM) including tables, code blocks, task lists, and more.
JSON Formatter
Format, validate, and compress JSON. Tree view, error detection with line/column numbers, copy formatted or minified output. All client-side.
CodeTools Toolbox - Free online developer tools.