💻 Developer & Data
Format and validate JSON, XML, YAML and SQL, test regex and cron, encode data, and handle security, IDs and networking — all client-side in your browser.
46 free tools across 4 categories.
Data Formats & Validation (21 tools)
CSV Viewer & Explorer
View, explore, and diagnose CSV data instantly. Table view with sorting, filtering, and RFC 4180 error diagnostics.
CSV ↔ JSON Converter
CSV ↔ JSON converter. Smart parsing with PapaParse.
HTML Formatter & Beautifier
Format & beautify HTML. Minify HTML for production. Preserves script/style, handles void elements correctly.
JSON Compare
Compare two JSON objects. Find added/removed/changed keys.
JSON Escape / Unescape
Escape and unescape JSON strings. Convert special chars to JSON-safe sequences. Decode escaped strings.
JSON Formatter & Validator
Format, validate, minify JSON. Error line detection.
JSON Minifier
Minify and compress JSON. Strip whitespace, reduce file size. Size comparison stats.
JSON Schema Generator
Generate JSON Schema from JSON. Auto-detects types.
JSON to CSV Converter
Convert JSON to CSV instantly. Paste JSON and get clean CSV output. Free, browser-based, zero-dependency.
JSON to SQL Converter
Convert JSON to SQL INSERT/CREATE TABLE statements. MySQL, PostgreSQL, SQLite, MSSQL. Nested flattening.
JSON ↔ YAML Converter
Convert JSON to YAML and YAML to JSON. js-yaml powered, bidirectional. Handles nested objects and arrays.
JSONPath Tester
Evaluate JSONPath queries. Select data from JSON.
OpenAPI/Swagger Viewer
Parse OpenAPI 3.x and Swagger 2.0 specs into a collapsible tree. Color-coded HTTP method badges. 100% client-side.
SQL Formatter
Format SQL. MySQL, PostgreSQL, SQLite. Beautify/minify.
SQL to JSON Converter
Convert SQL CREATE TABLE + INSERT to JSON. Multi-dialect, big-int safe.
XML Formatter & Validator
Format & validate XML. DOMParser error detection.
XML to CSV Converter
Convert XML to CSV with auto-detection of repeated records and dot-notation nested flattening. Browser-based, zero data leakage.
XML ↔ JSON Converter
Bidirectional XML ↔ JSON conversion. Recursive mapping.
XPath Tester & Evaluator
Test and evaluate XPath expressions against XML documents instantly. Query XML nodes with XPath 1.0, view results with generated paths. Free, browser-based, zero-dependency.
XSD Generator & Validator
Generate XSD schema from XML, or validate XML against XSD. Zero-dependency, browser-based.
YAML Validator
Validate YAML, convert to JSON. Error line detection.
Security & Network (10 tools)
HTTP Header Checker
Check HTTP response headers for any URL. View status, security, cache headers. Free developer tool.
Hash Generator
SHA-256, SHA-1, SHA-512. Web Crypto API.
IP Subnet Calculator
Calculate subnet details from IP + mask. Network, broadcast, usable hosts, wildcard mask. IPv4.
JWT Decoder
Decode JWT tokens. View header, payload, expiration.
Password Generator
Generate strong, random passwords. Configurable length.
Password Strength Checker
Entropy score, crack time, improvement tips.
SSH Key Generator
Generate SSH key pairs. RSA, ECDSA. PEM format.
SSL Certificate Decoder
Decode SSL/X.509 certificates. View Subject, Issuer, Validity, Fingerprint, Public Key. Free developer tool.
Text Encryptor / Decryptor
AES-256-GCM encryption. Password-protected messages.
What Is My IP Address
Check your public IPv4 & IPv6, ISP, and location instantly.
Code & Build Helpers (9 tools)
Cron Expression Builder
Visual cron builder. Human-readable. Presets included.
Dockerfile & Docker Compose Generator
Generate Dockerfile and compose files for Node, Python, Go, Java. Pick DB, ports, env vars. No Docker experience needed.
Function Graph Plotter
Math function graphing. sin, cos, x², multi-function.
JSON to Java POJO/DTO Converter
Convert JSON to Java POJO classes with Lombok, Jackson, nested objects. Free online converter, no sign-up.
JSON to TypeScript Generator
Convert JSON to TypeScript interfaces, types, and enums. Optional readonly, strict null checks.
Regex Explainer
Translate regex to human language. Token-by-token explanation.
Regex Tester
Test regex in real-time. Highlight matches, groups.
Scientific Calculator
Trig, log, sqrt, power. Expression input with history.
cURL to Code Converter
Convert curl commands to Python, Node.js, and Java code. Parse -X, -H, -d flags. Free developer tool.
Encoding & IDs (6 tools)
Base64 Encoder & Decoder
Encode and decode Base64 strings. Essential developer utility.
HTML Entity Encoder & Decoder
Encode/decode HTML entities. XSS prevention.
Number Base Converter
Binary, octal, decimal, hex. Real-time conversion.
URL Encoder & Decoder
Encode/decode URL strings. Percent-encoding tool.
UUID Generator
Generate UUID v4 identifiers. Browser crypto API.
Unix Timestamp Converter
Convert Unix timestamps to dates and back. Bidirectional.
How to Choose the Right Tool
| Your goal | Use this tool |
|---|---|
| Format and validate messy JSON | JSON Formatter & Validator |
| Test a regex pattern with live highlighting | Regex Tester |
| Decode a JWT token to inspect claims | JWT Decoder |
| Convert JSON to typed TypeScript interfaces | JSON to TypeScript Generator |
| Generate a cryptographically secure UUID | UUID Generator |
| Build a cron expression visually | Cron Expression Builder |
Frequently Asked Questions
JSON Formatter vs JSON Minifier — when should I use each?
Use the JSON Formatter when you need to read, debug, or validate JSON — it adds indentation, syntax highlighting, and pinpoints errors by line. Use the JSON Minifier for production deployment to strip all whitespace and reduce file size, with before/after size comparison stats. Format for development, minify for production — they're complementary tools in the same workflow.
Which encoding tool should I use — Base64, URL Encode, or HTML Entity?
Each serves a different purpose: Base64 Encoder converts binary data to ASCII text (images in CSS, API authentication tokens). URL Encoder makes text safe for query strings (spaces become %20, special characters escaped). HTML Entity Encoder escapes characters for HTML safety (< becomes <) and prevents XSS. Use Base64 for data transport, URL Encode for web addresses, HTML Entity for embedding code in pages.
Is the Regex Tester using a real regex engine — and how does the Explainer help?
Yes. The Regex Tester uses JavaScript's built-in RegExp engine — the same one powering browser form validation. It supports flags (g, i, m), capture groups, and real-time match highlighting. The companion Regex Explainer breaks complex patterns into plain English token by token, showing what each part of the expression matches. Together they're a learning and debugging pair for regular expressions.
JSON to SQL vs JSON to Java vs JSON to TypeScript — which converter for which use case?
The JSON to SQL Converter generates CREATE TABLE and INSERT statements for MySQL, PostgreSQL, SQLite, and MSSQL — use it to seed databases from JSON data. The JSON to Java POJO Converter produces typed Java classes with Lombok and Jackson annotations for backend development. The JSON to TypeScript Generator outputs interfaces, types, and enums with optional readonly and strict null checks for frontend work. Choose based on your target language, not the JSON source.
Can these tools handle sensitive data — what's the client-side privacy model?
All developer tools process data exclusively in your browser using JavaScript APIs — nothing is transmitted to a server. This is critical when working with production data, API keys embedded in JSON, authentication tokens, or proprietary algorithms. The JWT Decoder parses tokens locally, the Hash Generator uses the Web Crypto API, and the Text Encryptor performs AES-256-GCM encryption entirely in-memory. Disconnect your internet after page load to verify — the tools still function.