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Developer Tools

273 apps

Developer Tools: Build Templates

Developer Tools: Code & Configuration

Developer Tools: Code & Validation

Code / Diff · ConvertCode Formatter DeskFormat JavaScript, TypeScript, JSON, CSS, HTML, Markdown or YAML. Choose spacing and style, then review the changes.SVG / PNG · ConvertCode Snippet Image MakerTurn code into a clear SVG or PNG image. Choose colors, add a title and show line numbers for sharing or teaching.Code / Token tree · ConvertCode Token InspectorExplore how a code highlighter labels words and symbols. See which parts are keywords, strings, comments and other code types.JSON5 / JSON · ConvertConfiguration Comment EditorEdit a JSON5 file with comments. Check its values and download standard JSON for apps that do not accept comments.Text / JSON · ConvertCSV Field ValidatorApply named validation rules to CSV columns and download a row-by-row error report.HTML / CSS · ConvertCustom Code Highlighter BuilderChoose your own code highlight colors. Preview the theme and download its CSS and a sample HTML code card.Text / JSON · ConvertData Contract TesterCheck a batch of JSON records against the same rules. Download a report showing which records and fields need fixing.HTML / CSS · ConvertEmbeddable Code Card MakerMake a colorful code card for a web page. Download one HTML file with its styles included and no extra files to load.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

Developer Tools: Developer Utilities

Developer Tools: Document & Data Services

Developer Tools: Explore a Pattern

Developer Tools: Filter & Reshape

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

Developer Tools: IDs & Codes

Developer Tools: Inspect & Validate