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Developer Tools
273 appsDeveloper Tools: Code & Validation
Code / Diff · ConvertFormatting Rule DemonstratorSee how code formatting rules change your code. Compare the original and formatted versions line by line.Text / JSON · ConvertInput Validation PlaygroundCheck sample emails, URLs, identifiers, dates, and numbers against visible validation rules.Text / JSON · ConvertJSON Difference ExplorerCompare two JSON files and find what changed. Open each difference to see added, removed and edited values.Text / JSON · ConvertJSON Schema ValidatorCheck JSON against a JSON Schema. Find missing fields, wrong value types and other errors with their exact locations.Code / JSON · ConvertLanguage Detection PreviewGuess the programming language of a code snippet. Compare the top two matches and check the highlighted result.JavaScript RegExp · ConvertRegex Capture Group ReferenceFind named and numbered capture groups in a regular expression. See where each group starts and how it is used.JavaScript RegExp · ConvertRegular Expression AST ExplorerSee how a JavaScript regular expression is built. Explore its parts in a tree and find syntax errors without running the pattern.SQL · ConvertSQL Style ComparisonCompare three ways to format the same SQL query. Try different spacing and keyword styles, then download each version.HTML / CSS · ConvertSyntax Theme ComparatorCompare three color themes for the same code. Preview how keywords, text and comments look before choosing a style.
Developer Tools: Common Formats
Regular Expression · GenerateCoupon Code Regex Sample GeneratorGenerate sample coupon codes from a simple editable promotion pattern.Regular Expression · GenerateDate Regex Sample GeneratorGenerate ISO-shaped date strings for parser and form tests, then check real calendar rules separately.Regular Expression · GenerateEmail Regex Sample GeneratorGenerate example email addresses on reserved example and test domains.Regular Expression · GenerateFilename Regex Sample GeneratorGenerate lowercase file names with common test extensions and no folder paths.Regular Expression · GenerateHex Color Regex Sample GeneratorGenerate uppercase six-digit hexadecimal colors for design and form tests.Regular Expression · GenerateIPv4 Regex Sample GeneratorGenerate IPv4 values whose four number parts stay between 0 and 255.Regular Expression · GenerateOrder Number Regex Sample GeneratorGenerate order-number examples for receipt, search, and import testing.Regular Expression · GeneratePhone Regex Sample GeneratorGenerate North American phone-shaped examples for formatting and input tests.Regular Expression · GenerateSKU Regex Sample GeneratorGenerate product SKU examples with letters, digits, and fixed separators.Regular Expression · GenerateTracking Code Regex Sample GeneratorGenerate fake tracking-shaped codes without using a real carrier number.Regular Expression · GenerateURL Slug Regex Sample GeneratorGenerate lowercase, hyphen-separated slug values for route and form testing.Regular Expression · GenerateUsername Regex Sample GeneratorGenerate lowercase usernames that follow a clear length and character rule.
Developer Tools: CSS & JavaScript
CSS / JSON · ConvertCSS Declaration ExplorerSearch CSS property names and values, find important declarations, and export their locations for stylesheet cleanup.CSS / JSON · ConvertCSS Prefix PreviewAdd vendor prefixes for browsers you choose. See resolved browser versions and download the resulting CSS and source map.CSS / JSON · ConvertCSS Rule InventoryCount CSS rules, selectors, properties, and at-rules. See repeated values and download a complete stylesheet inventory.CSS / JSON · ConvertCSS Syntax ValidatorCheck CSS syntax, find errors by line and column, and explore a structured tree without applying the styles to your page.CSS / JSON · ConvertCSS Transformation PlaygroundFlatten nested CSS, add browser prefixes, and remove comments with a before-and-after view and downloadable CSS.JavaScript / source map · ConvertJavaScript MinifierMake JavaScript smaller with controls for compression, variable names, and comments. Download the code and an optional source map.CSS / JSON · ConvertLegacy CSS Compatibility DiffCompare CSS before and after browser-prefix changes. Inspect added and removed declarations for your chosen browser targets.JavaScript / source map · ConvertMinification Impact ViewerCompare original, minified, and formatted JavaScript. Measure UTF-8 and gzip sizes, then download code and source maps.
Developer Tools: Developer Utilities
GTIN / SSCC · ConvertBarcode Check Digit CalculatorCalculate or verify the GS1 check digit for GTIN-8, UPC-A, EAN-13, GTIN-14, and SSCC-18 codes.CSV · ConvertBarcode CSV AuditorCheck a CSV column of product barcodes for invalid lengths, non-digit characters, and incorrect check digits.Unicode · ConvertDomain Character InspectorCheck the exact characters in a domain name. See Unicode codes and decoded Punycode to spot lookalike letters.Paths · ConvertGlob Pattern TesterTest a file glob against a list of paths. See which filenames match your pattern before using it in a script.Text · ConvertHTML Entity DecoderDecode named and numeric HTML entities into plain text without rendering the result as HTML.HTML · ConvertHTML Entity EncoderConvert text to HTML entities. Escape symbols such as < and & so they can appear as text in HTML code.Domain · ConvertIDN / Punycode ConverterConvert international domain names between Unicode and Punycode. Compare readable names with their xn-- form.SemVer · ConvertSemantic Version Range CheckerCheck which package versions fit an npm version range. Test rules such as ^1.2.3 against a list of versions.Unicode · ConvertUnicode Entity ExplorerInspect Unicode characters one by one. See each character's number, UTF-8 bytes and HTML entity code.
Developer Tools: Document & Data Services
JSON / jq recipe · ConvertAPI Response ReshaperReshape a JSON API response with jq. Save the input, query and result together so you can repeat the same steps later.ZIP / CSV · ConvertArchive Text SearchSearch text inside a ZIP file. Choose a file pattern and search rule, then download matching lines with their filenames.
Developer Tools: Explore a Pattern
Regular Expression · AnalyzeLong Regex Sample FinderGenerate many matches and keep the longest examples found in that sample run.Regular Expression · AnalyzeRegex Coverage Pack MakerMake a small test pack that covers several lengths and removes duplicate strings.Regular Expression · AnalyzeRegex Sample Length ExplorerGenerate a test batch and compare its shortest, longest, and average string lengths.Regular Expression · AnalyzeShort Regex Sample FinderGenerate many matches and keep the shortest examples found in that sample run.
Developer Tools: Filter & Reshape
JSON · ConvertJSON Array FilterFilter a JSON array with a clear JSONata condition and keep the matching objects.JSON · ConvertJSON Array FlattenerPull values from arrays inside records into one simple result sequence.JSON · ConvertJSON Array GrouperGroup array records by a field and return one object with a key for each group.JSON · ConvertJSON Array SorterSort an array by text or numbers with JSONata's order-by operator.JSON · ConvertJSON Field PickerTurn each object into a smaller object with a chosen set of fields.JSON · ConvertJSON Field RenamerBuild new objects with renamed fields while keeping the original JSON unchanged.JSON · ConvertJSON Object ReshaperCombine fields, filters, and nested results into a cleaner object for another system.
Developer Tools: Find Code Parts
JavaScript · ExtractJavaScript Arrow Function FinderList arrow functions with inferred names, parameters, async state, and source lines.JavaScript · ExtractJavaScript Async Function FinderFind async declarations, expressions, and arrows with names, parameters, and lines.JavaScript · ExtractJavaScript Await Expression FinderList awaited expressions with their readable source text and exact line.JavaScript · ExtractJavaScript Call Expression FinderList function and method calls with readable callee names, argument counts, and lines.JavaScript · ExtractJavaScript Class InventoryList class declarations and expressions with inheritance and method counts.JavaScript · ExtractJavaScript Comment ExtractorExtract comments with their type, text, line, and character count.JavaScript · ExtractJavaScript Dynamic Import FinderList dynamic import expressions, source values, and exact locations.JavaScript · ExtractJavaScript Event Listener FinderList event listener calls, target expressions, event names, and lines.JavaScript · ExtractJavaScript Export InventoryFind export statements, names, source modules, lines, and export kinds.JavaScript · ExtractJavaScript Function InventoryFind function declarations and expressions with names, parameters, lines, and flags.JavaScript · ExtractJavaScript Import InventoryFind static imports, source packages, local names, and import kinds.JavaScript · ExtractJavaScript Number Literal ExtractorExtract decimal, hex, binary, octal, bigint, and exponent number literals.JavaScript · ExtractJavaScript Object Key FinderFind object property keys, method keys, computed state, and source lines.JavaScript · ExtractJavaScript Optional Chaining FinderList optional member and call expressions with their source lines.JavaScript · ExtractJavaScript String Literal ExtractorExtract string and template text with quote type, length, and source line.JavaScript · ExtractJavaScript Variable Declaration FinderFind declared names, declaration kinds, initial values, lines, and nesting depth.
Developer Tools: Generate Samples
Regular Expression · GenerateBulk Regex Sample GeneratorGenerate up to 250 matching strings for forms, imports, and test fixtures.Regular Expression · GenerateRegex Example GeneratorEnter a regular expression and make clear example strings that match it.Regular Expression · GenerateSeeded Regex Sample GeneratorUse a seed so the same pattern and settings make the same strings again.Regular Expression · GenerateUnique Regex Sample GeneratorTry extra generations and keep only distinct strings that match your pattern.
Developer Tools: IDs & Codes
CSV / JSON / TXT · ConvertRandom Invite Code BatcherCreate unique offline invitation codes with a readable alphabet and optional event prefix, then download the full batch.CSV / JSON · ConvertRecord ID Migration MapperMap old record IDs to fresh UUID v4 or v7 values, review repeated IDs, and export a complete local lookup table.CSV / JSON / TXT · ConvertShort Identifier GeneratorGenerate random short IDs using your chosen alphabet, length and prefix, then export a batch as CSV, JSON or text.
Developer Tools: Inspect & Validate
Liquid · CheckLiquid Filter InventoryFind Liquid filter names, counts, and source lines without rendering the output.Liquid · CheckLiquid Output Escaping CheckerList output expressions and confirm that Bookify's preview applies default HTML escaping.Liquid · CheckLiquid Syntax CheckerParse a Liquid template with strict filters and show a clear local syntax result.Liquid · CheckLiquid Tag InventoryList if, for, assign, capture, case, and other Liquid tags with line numbers.Liquid · CheckLiquid Variable FinderFind root variables and full nested paths without rendering the template.
Developer Tools: JSON Web Keys
JWT · GenerateJWK Key Pair GeneratorGenerate an RS256 or ES256 JWK pair and a stable key ID in your browser.JWT · CheckJWK Thumbprint CalculatorCalculate the RFC 7638 SHA-256 thumbprint and thumbprint URI for a JWK.JWT · ConvertJWK to PEM ConverterConvert an RSA or EC JWK into a public SPKI or private PKCS8 PEM key.JWT · CheckJWKS InspectorList key IDs, algorithms, uses, public fields, and thumbprints in a JWKS file.JWT · ExtractJWKS Key FinderSearch a pasted JWKS for a matching kid and copy the exact public key.JWT · ConvertPEM to JWK ConverterConvert a public SPKI or private PKCS8 RSA or EC key into JWK format.JWT · GenerateSymmetric JWK GeneratorGenerate a 256-bit secret JWK for HS256 signing or A256GCM encryption.
Developer Tools: JWS & JWE
JWT · CheckJWE Text DecryptorDecrypt a direct A256GCM compact JWE with the passphrase used to make it.JWT · GenerateJWE Text EncryptorProtect text with direct A256GCM encryption and a passphrase-derived local key.JWT · GenerateJWS Message SignerCreate a compact JWS for a text message with a shared secret kept in this tab.JWT · CheckJWS Signature VerifierCheck an HS256 compact JWS and reveal its text only after the signature matches.
Developer Tools: JWT Signing & Checks
JWT · CheckJWT Claims ValidatorVerify an HS256 token and require the issuer and audience your app expects.JWT · GenerateJWT HS256 SignerTurn JSON claims into a signed HS256 token with a secret that stays in this tab.JWT · GenerateJWT Private Key SignerCreate an RS256 or ES256 token from claims and a local JWK or PKCS8 private key.JWT · CheckJWT Public Key VerifierVerify an RS256 or ES256 token with a local public JWK or SPKI key.JWT · CheckJWT Signature VerifierCheck whether a JWT matches a shared secret, then read the verified claims.