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Developer Tools
Handy developer utilities that work offline in your browser — format and minify code, generate UUIDs and passwords, decode JWTs, test regex, hash text and more. No installs, no data sent to a server.
Developers spend a surprising amount of time on small, repetitive tasks that fall outside the main coding workflow: prettifying a JSON blob from an API response, generating a random UUID for a test fixture, hashing a string to verify a checksum, decoding a JWT to inspect its claims, or testing a regex pattern against sample input. Each of these takes only seconds with the right tool — but finding, installing, or writing that tool can take minutes.
Our developer tools category assembles the utilities that come up most often in a typical engineering day, all available instantly in the browser. There is no package to install, no Docker container to spin up, and no account to create. Open a tool, paste your input, get your output, and move on.
Security is a first-class concern in this category. All hashing, encoding, and token-inspection operations run locally using the Web Crypto API and standard JavaScript — your secrets, tokens, and private data are never sent to any server.
Who uses Developer Tools?
Full-stack developers
Format and validate JSON API responses, decode JWT tokens to inspect headers and payloads, generate UUIDs for database seeds, and minify JavaScript or CSS before deployment.
DevOps & platform engineers
Hash configuration values for comparison, generate strong random passwords for service accounts, encode environment variable values in Base64, and verify URL-encoded strings in logs.
Security engineers
Inspect JWT claims without a library, compute SHA-256 or MD5 hashes for file integrity checks, decode Base64-encoded certificates, and test regex patterns against log samples.
QA engineers
Generate realistic UUIDs and random strings for test data, pretty-print minified JSON payloads for manual review, and regex-test expected output patterns before writing assertions.
97 Developer Tools
JSON Formatter
Pretty-print and beautify JSON with custom indent and optional key sorting.
JSON Minifier
Minify and compress JSON by removing all unnecessary whitespace.
JSON Validator
Check whether JSON is valid and pinpoint errors by line and column.
CSV to JSON
Convert CSV data into clean JSON, with header and delimiter options.
JSON to TypeScript Converter
Generate TypeScript interfaces from any JSON object or array instantly.
JSON to Java Class Converter
Turn JSON into Java POJO classes with optional getters and setters.
JSON to Python Dict Converter
Convert JSON into a Python dict literal, TypedDict, or dataclass.
JSON to PHP Array Converter
Convert JSON into a PHP array using short or long array syntax.
XML to JSON Converter
Convert XML into readable JSON with attributes and text preserved.
CSV Delimiter Converter
Convert between comma, semicolon, tab and pipe delimited data, quote-aware.
JSON Escape / Unescape
Escape text into a safe JSON string literal, or unescape one back to plain text.
CSV to XML
Convert CSV data into well-formed XML with custom root and row element names.
HTTP Header Parser
Parse raw HTTP headers into a clean table with notes on common headers.
Cron Expression Explainer
Translate a cron expression into a clear plain-English schedule description.
Hex Color Extractor
Pull every hex color code out of CSS or text and count each unique value.
HTML Tag Extractor
List every unique HTML tag name in a page with occurrence counts.
ISO Date Converter
Convert many date formats into clean ISO 8601 timestamps, one per line.
JSON to CSV
Convert a JSON array of objects into clean, spreadsheet-ready CSV.
Meta Title Length Checker
Check meta title length in characters and estimated pixel width against Google limits.
Slug to Title Converter
Turn URL slugs like my-blog-post into clean, readable Title Case headings.
SQL Formatter
Beautify SQL queries with uppercase keywords, clause breaks and clean indentation.
Twitter Card Generator
Build Twitter (X) Card meta tags for rich link previews from simple fields.
ULID Generator
Generate lexicographically sortable ULIDs with a timestamp prefix and monotonic ordering.
URL Parser
Break any URL into protocol, host, port, path, query parameters and fragment.
Canonical Tag Generator
Turn a list of URLs into rel=canonical link tags, with optional normalization.
Domain Extractor from URLs
Extract the unique domain names from a list of URLs and count each one.
Domain Name Generator
Combine your keywords with prefixes, suffixes and TLDs to brainstorm domain ideas.
Meta Description Length Checker
Check meta description length in characters and estimated pixel width against Google limits.
Meta Tag Extractor
Pull every meta tag, including Open Graph and Twitter Card, into a table.
Nano ID Generator
Generate compact, URL-safe Nano IDs with a configurable size and custom alphabet.
SQL Minifier
Compress SQL into a single line by removing comments and extra whitespace.
Timezone Converter
Convert a date and time between timezones using accurate IANA zone data.
URL Builder
Assemble a valid URL from a protocol, host, path, query pairs and fragment.
Canonical URL Checker
Paste page HTML to find its rel=canonical tag and compare it against an expected URL.
Hreflang Tag Generator
Create hreflang link tags for multilingual sites, with an optional x-default.
HTML Formatter
Indent and beautify HTML with clean nesting while preserving pre and script blocks.
Image URL Extractor
Extract all image src and srcset URLs from HTML, one per line.
Query String Builder
Turn key=value lines into a properly encoded URL query string instantly.
Random String Generator
Generate random strings with a chosen length, count and mix of letters, digits and symbols.
SERP Snippet Preview
Preview how your title, URL and description will appear in Google search results.
Subdomain Extractor
Extract the subdomain portion from a list of URLs and count each unique one.
User Agent Parser
Parse user-agent strings into browser, version, operating system and device.
Anchor Text Extractor
Extract link anchor text paired with its href from HTML into a table.
Hash Generator
Generate MD5, SHA-1, SHA-256 and SHA-512 hashes of any text at once in a table.
HTML Minifier
Shrink HTML by collapsing whitespace and optionally removing comments.
Meta Title Generator
Generate SEO-friendly meta title variations from a keyword, brand and template patterns.
MIME Type Lookup
Look up the MIME type for a file extension, or find extensions for a MIME type.
Query Parameter Extractor
Extract decoded key/value query parameters from a list of URLs into a table.
URL to Hostname Converter
Extract just the hostname from a list of URLs, with optional www stripping and dedupe.
UTM Builder
Add UTM campaign parameters to a URL for accurate marketing analytics.
XML Sitemap Generator
Turn a list of URLs into a valid XML sitemap with changefreq, priority and lastmod.
CSS Class Extractor
List every unique CSS class used in HTML with usage counts.
CSS Formatter
Beautify CSS with one declaration per line and clean, consistent indentation.
DNS Lookup Tool
Look up live DNS records (A, AAAA, MX, TXT, NS, CNAME, SOA, CAA) for any domain.
File Extension Extractor
Extract file extensions from filenames or URLs and count each unique type.
MD5 Generator
Generate MD5 hashes of text, with an option to hash each line separately.
Meta Description Generator
Generate SEO meta description variations from a keyword, benefit and call to action.
Regex Tester
Test a regular expression against text and see every match, index and group.
Relative to Absolute URL Converter
Resolve relative paths into full absolute URLs against a base URL you provide.
Sitemap URL Extractor
Extract every URL and lastmod date from a sitemap or sitemap index XML.
UTM URL Parser
Extract UTM campaign parameters from a list of URLs into a clear table.
CSS Minifier
Compress CSS by removing comments and whitespace for smaller stylesheets.
Domain Age Checker
Check when a domain was registered and calculate its age using live RDAP data.
HTML ID Extractor
List every id attribute in HTML and flag duplicate ids that break pages.
Regex Generator
Generate ready-to-use regular expressions for emails, URLs, dates and more.
Regex Match Extractor
Extract every match of your own regular expression from text, safely.
Robots.txt Generator
Build a valid robots.txt file with allow/disallow rules, sitemap and crawl-delay.
SHA-256 Generator
Generate secure SHA-256 hashes of text, with an option to hash each line separately.
Sitemap Splitter
Split a large sitemap XML into smaller numbered sitemaps by a max-URL limit.
URL Case Converter
Lowercase the host and path of URLs while preserving case-sensitive query strings.
URL Length Checker
Measure URL lengths and flag ones too long for browsers or SEO best practice.
Bulk URL Validator
Check a list of URLs for valid structure and get a reason for every invalid one.
FAQ Schema Generator
Turn question and answer pairs into FAQPage JSON-LD structured data.
HMAC Generator
Generate keyed HMAC signatures with MD5, SHA-256 or SHA-512 and hex or base64 output.
HTTP Status Code Checker
Check the live HTTP status code of any URL, including its redirect chain and meaning.
JavaScript Formatter
Pretty-print minified or messy JavaScript with consistent indentation.
JavaScript Minifier
Shrink JavaScript by stripping comments and collapsing whitespace safely.
JavaScript URL Extractor
Extract script src URLs and inline javascript: links from HTML.
Robots.txt Tester
Test whether URLs are allowed or blocked by your robots.txt rules for a given crawler.
URL Cleaner
Normalise URLs by stripping fragments, trailing slashes and default ports.
Words Between Characters
Extract every piece of text that sits between your chosen start and end characters.
Breadcrumb Schema Generator
Create BreadcrumbList JSON-LD structured data from name and URL lines.
Cron Expression Generator
Build cron expressions from fields or presets and see a plain-English description.
Open Graph Tag Generator
Generate Open Graph meta tags for rich link previews on social media and messaging apps.
Redirect Chain Checker
Trace every redirect a URL follows, with status codes, timing and the final destination.
Text Between Brackets
Extract everything enclosed in round, square, curly or angle brackets.
Tracking Parameter Remover
Strip UTM, fbclid, gclid and other tracking parameters from URLs.
Bulk URL Status Checker
Check the live HTTP status of up to 20 URLs at once, with redirects and timing per link.
Text Between Quotes
Extract every quoted string using single, double or backtick quotes.
UUID Generator
Generate random version-4 UUIDs in bulk, with format options.
Random Number Generator
Generate random integers in any range, in bulk, with or without duplicates.
Password Generator
Create strong, random passwords with adjustable length and character sets.
CSV to SQL Converter
Turn CSV rows into ready-to-run SQL INSERT statements with a chosen table name.
JWT Decoder
Decode a JWT's header and payload without verifying the signature.
JSON to TOML Converter
Convert a JSON object into clean TOML configuration syntax with nested tables.
Query String Parser
Split a URL query string into a clean table of decoded key/value parameters.
CSV to HTML Table
Convert CSV data into a clean, semantic HTML table with header options.
How to choose the right developer tool
If you have a minified or machine-produced string you need to read, the JSON Formatter or Code Beautifier is your first stop. For identity and randomness needs (UUIDs, tokens, passwords), the UUID Generator and Password Generator handle both. When you need to verify a hash or compute a checksum, the Hash Generator supports MD5, SHA-1, SHA-256, and SHA-512. To inspect a JWT without a library, the JWT Decoder shows header, payload, and signature in a readable panel. For pattern-matching problems, the Regex Tester lets you write, test, and iterate on expressions against real sample text. If you are unsure which tool fits, describe your input format — most tasks in this category map to one obvious tool.