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Code Formatters & Validators
Beautify, minify, validate and lint JSON, HTML, CSS, JavaScript, SQL, XML, YAML and more. 41 free tools that run in your browser, no sign-up needed.
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JSON FormatterBeautify, minify and validate JSON, with a collapsible tree view.SQL Formatter & BeautifierFormat, beautify or minify SQL queries for MySQL, PostgreSQL and more.JavaScript BeautifierFormat and beautify messy or minified JavaScript, or minify it.HTML FormatterBeautify and indent HTML code with a live preview.CSS FormatterBeautify CSS with indent controls and optional property sorting.XML FormatterBeautify, validate and minify XML with a collapsible tree view.ZIP File CreatorCompress files and folders into a ZIP.YAML Validator & FormatterValidate, format and minify YAML, and convert YAML to JSON or back.HTML MinifierMinify HTML: strip comments and whitespace safely and see how many bytes you save.CSS MinifierMinify CSS with csso or a built-in engine and see the size saved instantly.JavaScript MinifierMinify JavaScript with Terser: compress, mangle and see how many bytes you save.JSON MinifierMinify and validate JSON, sort keys and see exactly how many bytes you save.Code Diff CheckerCompare two code files side by side or unified, with syntax colors and changes highlighted.IPv6 Expander & CompressorExpand IPv6 addresses to full form or compress them per RFC 5952, one or many at once.GraphQL FormatterPretty-print and indent GraphQL queries, mutations and schemas, or minify them, instantly.CSS ValidatorValidate CSS: syntax errors, unknown properties and invalid values by line, plus auto-fix.Gzip Compress / DecompressGzip or deflate text and files, get Base64 output, and decompress Base64 or .gz files.IBAN ValidatorCheck an IBAN's mod-97 checksum, country and length, and see its bank code and account parts.JavaScript Syntax CheckerCheck JavaScript for syntax errors with line and column, for any ES version, script or module.JSON Schema ValidatorValidate JSON against a JSON Schema (draft-07, 2019-09, 2020-12) with clickable error paths.Markdown FormatterBeautify Markdown with Prettier: list markers, prose wrap, aligned tables and live preview.PHP FormatterBeautify PHP code with Prettier PHP: PSR-12 style, indent and brace options, syntax errors.TypeScript FormatterFormat TypeScript and TSX code with Prettier: width, tabs, semicolons and quotes options.XML MinifierMinify and validate XML: strip whitespace and comments, keep CDATA, see the size savings.C# FormatterBeautify C# code online: Allman or K&R braces, indent size and line width, clang-format option.HTML ValidatorCheck HTML for errors and warnings with line numbers, locally or with the W3C Nu checker.Java FormatterBeautify Java code online: indent size, brace style and line width, with clang-format option.JavaScript ObfuscatorObfuscate JavaScript with string encoding, renaming and control-flow flattening presets.Phone Number FormatterFormat and validate lists of phone numbers to E.164, international or national style.Python FormatterFormat Python code in Black/Ruff style: line length, quote style, indent, copy or download.Responsive Design CheckerPreview any website at phone, tablet, laptop and desktop sizes side by side, with rotate and zoom.Browser Compatibility CheckerSearch CSS, JavaScript and HTML features and see which browser versions support them.Core Web Vitals CheckerCheck real-user LCP, INP and CLS for any URL or site and see if it passes Core Web Vitals.Heading Structure CheckerPaste HTML to see its H1-H6 outline and catch missing H1s, multiple H1s and skipped levels.Website Hosting CheckerFind out who hosts a website: hosting provider, IP addresses, ASN, network owner and location.Routing Number ValidatorCheck a US ABA routing number's checksum and format and see its Federal Reserve district.Spam Word CheckerScan an email subject and body for spam trigger words, excess caps, exclamation marks and risky links.Check Digit CalculatorCalculate or validate check digits for UPC, EAN, GTIN, SSCC, ISBN, ISSN and mod 11 codes.Luhn Algorithm CheckerValidate numbers with the Luhn mod 10 check or calculate the missing check digit, step by step.XSD ValidatorValidate XML against an XSD schema in your browser and see each error with its line number.Strftime Format BuilderBuild Python and C strftime format strings by clicking tokens, with a live preview and reference.
About Code Formatters & Validators
Beautify or minify JSON, HTML, CSS, JavaScript, SQL, XML and YAML, and catch syntax errors. Formatting makes minified or machine-generated code readable before you debug it.
Most used here: JSON Formatter, SQL Formatter & Beautifier and JavaScript Beautifier.