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