Free Developer & Data Tools

JSON formatters, CSV/JSON converters, regex testers, diff checkers, and private JWT debuggers.

• JSON Formatter & Validator: Beautify, minify, validate, and debug JSON payloads with syntax error detection.
• CSV ↔ JSON Data Converter: Bidirectionally convert between tabular CSV files and structured JSON arrays.
• Regex Playground & Explainer: Live regular expression tester with capture groups, matches, and pattern presets.
• Text & Code Diff Checker: Compare two texts or code files side-by-side with added/removed line highlighting.
• Base64 Encoder & Decoder: Encode strings and binary files to Base64 or decode Base64 back to UTF-8.
• Private JWT Inspector: Inspect JWT tokens safely in-browser without sending secrets to any cloud service.
• UUID & NanoID Generator: Bulk generation of cryptographically random UUID v4 and compact NanoIDs.
• Markdown Live Editor: Split-pane Markdown editor with live preview, HTML export, and download.
• URL & HTML Entity Encoder: Encode/decode URL percent-encoding query parameters and HTML entities.
• JSON to TypeScript & Zod: Infer strict TypeScript interfaces and Zod validation schemas from JSON objects.
• CSS Glassmorphism & Shadow: Design Apple-grade multi-layer box shadows and frosted glass backdrop blur.
• CSV to Markdown & SQL Table: Format raw CSV/TSV into GitHub Markdown tables, SQL INSERT queries, and HTML.
• Base & Radix Converter: Convert Decimal, Hex, Binary, and Octal with BigInt precision and bit formatting.
• Card & IBAN Validator: Luhn checksum for card numbers and ISO 7064 mod-97 checksum for IBANs.
• .gitignore Generator: Combine common language, OS, and IDE ignore rules into a ready-to-use .gitignore.
• SEO Meta Tag & Slug Generator: Generate title, description, Open Graph, and Twitter Card tags plus a clean URL slug.
• HTTP Status Code Reference: Search and browse common HTTP response status codes and what they mean.
• User-Agent Parser: Identify browser, engine, OS, and device type from a User-Agent string.
• YAML ↔ JSON Converter: Bidirectional conversion between human-readable YAML and structured JSON with formatting and download.
• Regex Match & Data Extractor: Extract emails, URLs, IPv4 addresses, phone numbers, UUIDs, or custom regex matches with deduplication and CSV export.
• Subnet & CIDR Calculator: Calculate IP subnet masks, wildcard masks, network and broadcast addresses, and usable host ranges.
• Cron Schedule Visualizer: Visualize the next 10 future execution timestamps for 5-part crontabs in local time and UTC.
• HTML Entity & Char Codes: Searchable catalog of HTML character entities, decimal and hex codes with one-click copy.
• SQL Query Beautifier: Format, uppercase keywords, indent clauses cleanly, or minify SQL queries client-side.
• CSS Gradient Studio: Design linear, radial, and conic CSS gradients with multi-stop color controls and copy-ready syntax.
• Hex / Binary Stream Inspector: Inspect raw binary streams and text in canonical 16-byte hexdump format with byte statistics and search.

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