Check if a website is online and see its hosting, WordPress detection, SSL, DNS, SEO and performance.
Compare the execution speed of 2+ JS snippets, run in an isolated Web Worker.
Format minified JavaScript or compact it, with strings, templates and regex handled safely.
Build an iOS/macOS Info.plist from common bundle/privacy keys.
Press a key to see its KeyboardEvent key/code/keyCode values live.
Read any website's sitemap, see its page structure as a tree and graph, and check titles, meta tags and status codes.
Preview a URL at common device viewport sizes.
Build an AWS IAM policy JSON document.
Show the SHA256 and MD5 fingerprint, type and size of an SSH public key and compare it with another.
Pretty-print a MongoDB query/document.
Analyze a query for potential performance issues.
Generate neumorphism CSS.
A browser stopwatch with lap times.
Show the IP address our server sees you connecting from.
Look up domain registration info.
Generate a scannable QR code.
Generate strong random passwords.
Generate passwords, API keys, AES keys, UUIDs, and RSA/SSH key pairs — all client-side.
Generate v4/v7 UUIDs in bulk.
Classic placeholder text for mockups.
Check which web platform features your browser supports.
Show your screen/viewport size live.
Test every key of a new or old keyboard: on-screen layout, double-press detection, rollover test, heatmap and typing speed.
Re-indent or minify CSS.
Convert a CSS length across px, rem, em, pt, and %.
Generate glassmorphism CSS.
Generate all standard favicon sizes.
Design CSS @keyframes animations.
Format and minify HTML markup.
Convert between Markdown and HTML.
Minify and clean up SVG markup.
Generate harmonious color palettes.
Visually build an HTML table.
Diff two HTML snapshots.
Encode or decode HTML entities.
Design and export CSS gradients.
Generate head meta/Open Graph/Twitter Card tags.
Design layered CSS box-shadows.
Convert a font file between TTF/OTF and WOFF.
Visually build Tailwind class combos.
Add a duration to a start time and see the resulting date/time.
Binary arithmetic plus a base converter.
Convert data sizes between bytes/KB/MB/GB/TB, decimal or binary.
Follow a web address through every redirect and see status codes, loops and HTTPS upgrades.
AND/OR/XOR/NOT/shift with a bit-level view.
Subnet math — network/broadcast address, netmask, host range.
Decode a MAC address's bit flags plus a best-effort vendor lookup.
Convert between seconds, HH:MM:SS, and human-readable durations.
Expand a CIDR block or address range into every individual IP address.
Four common percentage calculations in one place.
Generate an RFC 4193 Unique Local Address prefix for private IPv6 numbering.
Convert between Celsius, Fahrenheit, and Kelvin.
Generate random, locally-administered MAC addresses.
Convert IPv4 to its integer/hex form and IPv4-mapped IPv6.
Convert MAC address formats, get the IPv6 link-local address and the Wake-on-LAN magic packet.
Convert CIDR, subnet and wildcard masks and generate Cisco ACL lines.
Generate random TCP/UDP port numbers for dev servers and configs.
Find the holder, origin AS, announced prefix and BGP neighbours for an IP, prefix, AS number or hostname.
Convert bps/Mbps/etc. and estimate download time.
Hex arithmetic/bitwise ops plus a base converter.
Convert a time between zones with daylight saving handled, and find a meeting hour for everyone.
Searchable list of common TCP and UDP ports and the services that use them.
Calculate the TCP window you need and the real throughput given bandwidth, latency and packet loss.
Summarize IPv4 and IPv6 routes into the smallest list of prefixes or one summary route.
Convert text to/from 8-bit binary bytes.
Percent-encode or decode text, component or full-URI mode.
Convert text to/from decimal character codes.
Convert text to/from hex bytes.
Convert text to/from Unicode code points (U+XXXX).
Convert text to/from Base58 (Bitcoin alphabet).
Convert text to/from Base32 (RFC 4648).
Automatically detect and decode Base64, hex, URL encoding, gzip and more, layer by layer.
Convert any file to a Base64 data URI, entirely in your browser.
Convert Base64 to a hex byte string and back.
Convert a URL query string to a JSON object and back.
Test a pattern against text with live match highlighting and capture groups.
Evaluate a math expression with a real parser (no eval) — operators, functions, constants.
Randomize the order of lines.
Reshape a list — trim, dedupe, sort, wrap, and rejoin with any separator.
Strip empty/whitespace-only lines.
Live character, word, line, and sentence counts.
Convert between UPPER/lower/Title/camelCase/snake_case/etc.
Searchable reference of regex tokens, quantifiers, and common patterns.
Find/replace text with regex and whole-word options.
Normalize an email to its provider-canonical form for deduping.
Sort lines alphabetically, A-Z or Z-A.
Plain-text line diff with added/removed highlighting.
Search and copy from a curated set of common emoji, grouped by category.
Convert text into a URL-safe slug.
Render text as ASCII art by sampling a real rendered font, not a fixed glyph set.
Random common-English filler text.
Abbreviate words like "i18n" — first letter, middle count, last letter.
Spell out text using the NATO phonetic alphabet.
Convert between Arabic numbers and Roman numerals.
Remove repeated lines, keep the first occurrence.
Parse a phone number into its E.164 calling code, country, and national number.
Generate secure random tokens/API keys.
Encode or decode Base64 text and files.
Generate sortable, Crockford Base32-encoded ULIDs in bulk.
Test CORS behavior of an endpoint.
Generate MD5/SHA family hashes.
Hash or verify text with bcrypt, using PHP's native password_hash/password_verify.
Generate a live TOTP (RFC 6238) code from a Base32 secret or otpauth:// URI.
Compute an HMAC from a message and secret key (SHA-1/256/384/512).
Mask the middle of a string for redacting keys/emails in screenshots.
Look up a CVE ID or search by product: severity, CISA KEV status, exploit probability, affected products and references.
Encrypt/decrypt text with common ciphers.
Score vulnerabilities with CVSS 3.1: base, temporal and environmental scores and the vector string.
Read the version and creation time inside a UUID, and generate sortable UUID v7 values.
Validate an IBAN's mod-97 checksum and break it into country/BBAN.
Score a password's strength and estimate crack time, entirely client-side.
Generate a BIP39 mnemonic seed phrase (12-24 words) with correct entropy and checksum.
Build a Content-Security-Policy and find weaknesses in an existing one.
Pull IPs, domains, URLs, emails, hashes and CVEs out of text, and defang or refang links.
Check whether a password appears in known data breaches without sending it.
Find out which algorithm a hash came from, or checksum a file with MD5, SHA-1 and SHA-2.
Create the integrity attribute and HTML tag for scripts and stylesheets loaded from a CDN.
Decode an X.509 certificate or CSR: subject, issuer, validity, SANs, key and fingerprints.
Create an RFC 9116 security.txt file so researchers know how to report vulnerabilities.
Monitor SSL certificate expiry dates.
Carve a VPC CIDR into equal subnets.
Toggle Unix file permissions to build a chmod command.
Parse or build an AWS ARN.
Build a Terraform variables file.
Sample event payloads for S3/API Gateway/SNS/SQS/EventBridge.
Parse/build S3 URLs (virtual-hosted, path-style, s3://).
Look up AWS/GCP/Azure region codes.
Convert a docker run command into an equivalent docker-compose.yml service block.
Re-indent Terraform configuration.
Generate a GitHub Actions workflow for Node, Python, PHP, Go, Java, Rust, .NET, Docker or Pages.
Convert between plain JSON and DynamoDB AttributeValue JSON.
Manage and diff .env files.
Test which versions satisfy an npm-style semantic version range.
Convert a .env file to JSON or YAML and back.
Build an Apache .htaccess file for redirects, HTTPS, caching, compression and security, with Nginx rules.
Generate nginx server blocks.
Monitor site/service uptime.
Generate a Dockerfile for common stacks.
Build and explain cron expressions.
Generate a docker-compose.yml.
Parse a User-Agent string.
Generate Kubernetes manifests.
Searchable file extension <-> MIME type reference.
Build and send HTTP requests, inspect responses, save history.
Burst-test an endpoint to find its effective rate limit.
Fill in {{variable}} prompt templates and preview the resolved prompt.
Searchable reference of every standard HTTP response status code.
Build or decode an HTTP Authorization: Basic header.
Convert curl commands to fetch/Python/PHP/HTTPie and back.
Validate a chat completions request or function/tool schema shape.
Fetch a URL and explain its response headers, with a security-header grade.
Decode and inspect JWT header/payload, verify signatures.
Walk through an OAuth2 Authorization Code flow and inspect tokens.
Design REST endpoint specs and generate docs/mocks from them.
Compare two API responses and see a structured diff.
Estimate LLM prompt token count.
Run queries against any GraphQL endpoint and browse its schema.
Convert an OpenAPI/Swagger spec to a Postman Collection and back.
Get a unique inbox URL and inspect incoming webhook requests live.
Continuously monitor an endpoint for uptime/latency via cron.
WCAG text/background contrast ratio, AA/AAA pass-fail.
Convert between RGB and HSV/HSB, the model used by Photoshop/Figma color pickers.
Convert between hex codes and RGB values.
Pick a color, see it in HEX/RGB/HSL.
Convert between RGB and HSL.
Generate random hex colors (pastel/vibrant/dark).
Convert between CMYK (print) and RGB (screen) color values.
Browse Tailwind CSS's default color palette.
Convert between standard CSS named colors and hex codes.
Browse Google's Material Design color palette.
Build hreflang alternate-language link tags.
Build a sitemap.xml from a pasted URL list.
Build a robots.txt from rule groups.
Build a canonical link tag.
Build JSON-LD structured data for common types.
Build a .gitignore from checklists by language, editor, and OS.
Searchable reference of common git commands.
Generate a conventional-commit message.
Visualize and help resolve merge conflicts.
Find stale/merged branches to clean up.
Build shields.io badges for version, build, licence and downloads and copy them as Markdown or HTML.
Generate a changelog from commit history.
Generate release notes from merged PRs.
Diff two JSON documents.
Validate and format YAML documents.
Validate, pretty-print, and minify JSON.
Pretty-print and validate XML.
Convert between TOML and JSON/YAML.
Convert JSON to XML, mirroring our XML to JSON Converter's conventions.
Generate realistic sample JSON that follows a JSON Schema, with a repeatable seed.
Convert JSON to CSV with flattening, delimiters and Excel-friendly output.
Generate TypeScript, Go, Java, C# or Python types from sample JSON.
Build a JSON Schema visually from sample data.
Convert XML documents to JSON.
Test JSONPath expressions against sample JSON.
Re-indent Firestore security rules.
Validate and preview TOML as JSON.
Convert between CSV and JSON.
Convert a Java .properties file to JSON or YAML and back.
Convert a common YAML subset to JSON and back.
Convert CSV to a real .xlsx file and back.
Drag-select and crop an image.
Shrink an image via adjustable JPEG/WebP quality.
Preview SVG markup safely (rendered as an image, not injected).
Resize an image to exact dimensions.
Convert an image to a base64 data URI and back.
Turn a code snippet into a styled PNG with themes, window frames and line numbers.
Turn screenshots into polished images with device frames, gradients, shadows and text.
Rasterize SVG markup to PNG or JPEG at any size.
Convert an image between formats.
Generate a lightweight inline-SVG placeholder image, no network request.
Generate test email addresses on RFC 2606 reserved domains.
Generate fake phone numbers (US 555 exchange, etc).
Generate fake names/emails/usernames for testing.
Generate Luhn-valid dummy card numbers for sandbox testing.
Generate fake street addresses for testing.
Build sample APNs and FCM push payloads.
Validate a google-services.json against the expected Firebase config shape.
Build a .entitlements file (associated domains, app groups, push, iCloud, etc).
Generate all required app icon sizes.
Analyze keyword competitiveness.
Generate a mobile app privacy policy.
Find high-value ASO keywords.
Manage translation strings across locales.
List files/sizes inside an APK.
Generate App Store/Play Store metadata.
Generate app store release notes.
Convert between Unix timestamps and dates.
Recover the original URL from a Microsoft Safe Links wrapped link.
Break a URL down into protocol, host, path, query params, and hash.
Build a custom URI scheme deep link.
Build a cross-platform sms: link with a pre-filled message.
Build a Google Play Store link from a package name.
Build a mailto: link with subject/body/cc/bcc.
Build an Apple App Store link from an app ID.
Build a wa.me click-to-chat link.
Follow redirects to the final destination.
Create short redirect links.
Generate an EAN-13 barcode.
Convert CSV rows into INSERT statements.
Build MongoDB queries visually.
Format and beautify SQL queries.
Generate an ER diagram from a schema.
Parse INSERT statements into a JSON array.
Visualize table relationships.
Diff two schema/query snapshots.
Visualize an EXPLAIN plan.
Pretty-print raw stack traces.
Summarize error rates/patterns in logs.
Annotate screenshots to report bugs.
Search and tail uploaded log files.
Parse and summarize crash reports.