Developer tools
Developer tools cover the small jobs that interrupt coding: formatting JSON, XML, SQL, HTML, and CSS, testing a regular expression, reading a cron schedule, generating UUIDs, and converting Unix timestamps.
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JSON FormatterFormat and validate JSON with 2-space, 4-space, or tab indentation, sort keys alphabetically, and see the position of any syntax error.Regex TesterTest a JavaScript regular expression against sample text and see every match highlighted, with its position and capture groups listed.Unix Timestamp ConverterConvert a Unix timestamp in seconds or milliseconds to a readable date, or a date to a timestamp, in local time, UTC, and ISO 8601.UUID GeneratorGenerate up to 1,000 random version 4 UUIDs or time-ordered version 7 UUIDs at once, in lowercase or uppercase, ready to copy.SQL FormatterFormat a SQL query into readable, indented lines with optional uppercase keywords, for MySQL, PostgreSQL, SQLite, or SQL Server.JavaScript MinifierMinify JavaScript by removing whitespace and comments and optionally shortening local variable names, then compare the size before and after.
All 41 developer tools, A to Z
- .gitignore GeneratorGenerate a .gitignore file by ticking templates for Node.js, Python, PHP, Java, Go, Windows, macOS, VS Code, and JetBrains IDEs.
- Bitwise CalculatorApply bitwise AND, OR, or XOR to two hexadecimal numbers and read the result in binary, decimal, hexadecimal, and octal.
- Cron Expression GeneratorWrite or pick a five-field cron expression and see what each field means in plain English, plus the next five run times in local time.
- CSS FormatterFormat minified or untidy CSS into readable rules with one declaration per line and an indent of 2 spaces, 4 spaces, or tabs.
- CSS MinifierMinify CSS by stripping comments, line breaks, and extra spaces around braces and colons, then compare the byte size before and after.
- cURL BuilderBuild a cURL command from a URL, HTTP method, headers, and request body, with shell-safe single quotes and one option per line.
- Email Header AnalyzerPaste raw email headers to see the sender, routing hops with delays, and the SPF, DKIM, and DMARC results in a readable summary.
- Fake Data GeneratorGenerate fake test data with random names, example.com emails, phone numbers, cities, and birth dates as JSON or CSV, up to 5,000 rows.
- GraphQL FormatterFormat a GraphQL query, mutation, or schema with consistent indentation and one field per line, or minify it into a single compact line.
- GraphQL MinifierMinify a GraphQL query or schema by removing comments, commas, line breaks, and extra spaces so it fits on one line in a request body.
- HAR ViewerOpen a HAR file exported from browser developer tools and list every request with its method, status, type, size, and time taken.
- HTML FormatterFormat messy or minified HTML into indented, readable markup with 2 spaces, 4 spaces, or tabs, including inline CSS and scripts.
- HTML MinifierMinify HTML by removing comments and the whitespace between tags, then compare the byte size before and after with the percentage saved.
- HTML Table to MarkdownConvert an HTML table into a Markdown table, keeping the header row and cell text and dropping tags, styles, and attributes.
- HTTP Status CodesLook up HTTP status codes and what they mean, from 100 Continue to 504 Gateway Timeout, by searching for a number or a keyword.
- IPv6 Subnet CalculatorCalculate an IPv6 subnet from an address and prefix length: network address, first and last address, total addresses, and full notation.
- JavaScript BeautifierFormat minified or untidy JavaScript into readable code with consistent line breaks and an indent of 2 spaces, 4 spaces, or tabs.
- JavaScript MinifierMinify JavaScript by removing whitespace and comments and optionally shortening local variable names, then compare the size before and after.
- JSON AnalyzerAnalyze a JSON document: count objects, arrays, keys, and value types, measure nesting depth and size, and list the most frequent keys.
- JSON CompareCompare two JSON documents after formatting both and sorting their keys, so only real value differences show up, not key order.
- JSON FormatterFormat and validate JSON with 2-space, 4-space, or tab indentation, sort keys alphabetically, and see the position of any syntax error.
- JSON MinifierMinify JSON by removing all whitespace and line breaks, producing a single-line document that is valid and smaller to send or store.
- JSON Schema GeneratorGenerate a JSON Schema (draft 2020-12) from a sample JSON document, with inferred types, nested properties, and required key lists.
- JSON to TypeScriptGenerate TypeScript interfaces from a sample JSON document, with nested objects turned into separate named interfaces and typed arrays.
- JSON Tree ViewerView JSON as a collapsible tree: expand and collapse objects and arrays, see item counts, and spot the type of every value by color.
- Markdown Table GeneratorTurn CSV, TSV, or spreadsheet cells pasted from Excel into a Markdown table with aligned columns and a choice of text alignment.
- Markdown to HTMLConvert Markdown to clean, sanitized HTML code that you can copy or download, with support for tables, lists, links, and code blocks.
- Random File GeneratorCreate a test file of an exact size filled with random bytes, zeros, or repeating text, for checking upload limits and transfer speed.
- README GeneratorGenerate a README.md for a software project with a description, install and usage commands, contributing notes, and a license section.
- Regex ExplainerExplain a regular expression in plain English, token by token: character classes, groups, quantifiers, anchors, lookarounds, and flags.
- Regex TesterTest a JavaScript regular expression against sample text and see every match highlighted, with its position and capture groups listed.
- SQL FormatterFormat a SQL query into readable, indented lines with optional uppercase keywords, for MySQL, PostgreSQL, SQLite, or SQL Server.
- Subnet CalculatorCalculate the network address, broadcast address, subnet mask, wildcard mask, and usable host range from an IPv4 address and prefix.
- Subnet Cheat SheetLook up every IPv4 prefix length from /0 to /32 with its subnet mask, wildcard mask, total addresses, and usable host count.
- Syntax HighlighterAdd syntax highlighting to code in 30+ languages, preview the colored result, and copy it as HTML with class names for your own page.
- Token CounterEstimate how many tokens a text uses in a large language model from its character count, alongside exact character and word counts.
- Unix Timestamp ConverterConvert a Unix timestamp in seconds or milliseconds to a readable date, or a date to a timestamp, in local time, UTC, and ISO 8601.
- UUID GeneratorGenerate up to 1,000 random version 4 UUIDs or time-ordered version 7 UUIDs at once, in lowercase or uppercase, ready to copy.
- UUID v7 GeneratorGenerate time-ordered version 7 UUIDs that sort by creation time, up to 1,000 at once, from a millisecond timestamp plus random bits.
- VLSM CalculatorSplit an IPv4 network into subnets of different sizes with VLSM: enter the hosts needed per subnet and get each range and mask.
- XML FormatterFormat XML with two-space indentation and check that it is well-formed, with the parser error shown when a tag or attribute is broken.