35 tools · 100% client-side · works offline
Developer tools that actually work.
Format, validate, convert, debug — all in your browser. No uploads, no accounts.
⚙All Tools35
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JSON Formatter
Beautify or minify JSON with recursive key sorting, auto-repair, and structural analysis.
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JSON Validator
Validate JSON syntax with line-number error pinpointing and clear diagnostic descriptions.
JSON Minifier
Strip whitespace from JSON to minimize payload size with real-time byte comparison.
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JSON Diff
Find structural differences between two JSON objects with color-coded output.
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JSON to YAML
Convert JSON to clean, readable YAML instantly with recursive key sorting.
New
JSON to TypeScript & Zod
Transform JSON to production-ready TypeScript interfaces or Zod schemas instantly.
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JSON Schema Generator
Generate high-quality JSON Schemas from your data. Supports Draft 7 with AJV validation.
JSON Flatten & Unflatten
Flatten nested JSON into dot notation or unflatten back. Supports custom delimiters.
JSON String Escape
Escape or unescape JSON strings with language-specific literal generation.
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YAML to JSON
Convert YAML to structured JSON. Supports multi-document streams and NDJSON output.
XML Formatter
Beautify or minify XML data with syntax highlighting and real-time validation.
XML Minifier
Compress XML by removing comments, collapsing whitespace, and merging empty tags.
XML Validator
Validate XML well-formedness with line-number error pinpointing.
HTML Formatter
Beautify or minify HTML5 with nested CSS/JS support and structural analysis.
HTML Minifier
Minify HTML, CSS, and JavaScript with attribute stripping and advanced optimization.
HTML Validator
Validate HTML against industry standards. Detect syntax errors and accessibility violations.
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SQL Formatter
Indent and beautify SQL queries — supports MySQL, PostgreSQL, SQLite, and T-SQL.
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Base64 Encode / Decode
Encode and decode Base64 strings with full Unicode support via TextEncoder.
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URL Encode / Decode
Professional URL workbench with RFC 3986 support, deep decoding, and parameter tables.
HTML Entity Encoder
Encode or decode HTML entities instantly with full HTML5 coverage — named, decimal, hexadecimal.
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Hash Generator
Compute SHA-1, SHA-256, and SHA-512 digests via the Web Crypto API. 100% client-side.
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JWT Inspector
Decode JWT tokens — inspect header, payload, expiry countdown, and security analysis.
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API Tester
Send HTTP requests to any REST API with CORS proxy, response timing, and request history.
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cURL to Code
Convert cURL commands to Python, JavaScript, Go, PHP, and more. Uses a WASM parser.
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HTTP Error Explorer
Comprehensive guide to all HTTP status codes with causes, fixes, and best practices.
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UUID Generator
Generate RFC 9562 compliant UUID v4 and v7 identifiers in bulk.
ULID Generator
Generate, decode, and compare ULIDs with monotonic ordering and UUID conversion.
Lorem Ipsum Generator
Configurable placeholder text — paragraphs, sentences, or word count with HTML output.
Random Port Generator
Generate bias-free random TCP/UDP ports with IANA service lookup and conflict assessment.
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Regex Tester
Test and debug regular expressions with match highlighting, capture groups, and ReDoS protection.
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Markdown Preview
Real-time GFM previewer with KaTeX math rendering and synchronized scrolling.
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Code Diff Tool
High-precision code comparison with syntax highlighting, side-by-side view, and sync scroll.
Chmod Calculator
Calculate Linux file permissions in octal and symbolic notation with visual terminal preview.
Docker Compose Builder
Convert between Docker Run commands and Docker Compose files. Supports multiple services.
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Error Decoder
Decode stack traces and errors from Java, Python, JavaScript, Go, and Rust instantly.
⊞ Tool Collections
JSON Toolkit
Complete JSON development suite
Encoding Toolkit
Base64, URL, and HTML encoding
Data Conversion
Transform between data formats
Dev Utilities
Everyday developer productivity tools
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