Digital Domain Kit

Practical browser-based tools for public website checks, DNS, HTTP, structured data, security, and web implementation.

Popular tools

Frequently used tools across Digital Domain Kit.

Redirect Checker for Public URL Chains

Check a public HTTP or HTTPS URL from the DigitalDomainKit server and review the redirect chain one hop at a time. The tool validates the starting URL and each next Location target as public, then reports each checked step, status code, elapsed request time, final URL, and final status.

Image Compressor: Reduce PNG, JPEG, and WebP Files

Compress one PNG, JPEG, JPG, or WebP image in your browser. Preview the original and compressed result, adjust quality, compare file size, and download a same-format copy.

Image Resizer

Resize a single PNG, JPG, JPEG, or WebP image by entering exact pixel dimensions, previewing the original size, and downloading a browser-generated copy. The Image Resizer can keep the original aspect ratio while you change width or height, then saves the result with the requested dimensions included in the filename.

Subdomain Finder

Find publicly indexed subdomains for a domain using HackerTarget host search results.

Image Tools

Resize, compress, convert, and optimize images without uploading them.

Image Compressor: Reduce PNG, JPEG, and WebP Files

Compress one PNG, JPEG, JPG, or WebP image in your browser. Preview the original and compressed result, adjust quality, compare file size, and download a same-format copy.

Image Resizer

SEO & Web Tools

Check technical SEO details and generate search-ready website markup.

Sitemap Generator for Public Website Crawl Drafts

Generate a draft XML sitemap from a public HTTP or HTTPS starting URL. The tool crawls same-host links it can fetch from the DigitalDomainKit server, applies public-target validation, respects a selectable page limit, and lets you review, copy, or download the resulting sitemap XML.

Schema.org Entity Relationship Visualizer

Visualize Schema.org JSON-LD entities from a public webpage URL or pasted JSON-LD. The tool extracts typed entities, nested typed objects, @graph nodes, and root arrays, then displays a Mermaid relationship diagram, entity detail cards, raw parsed data, and an SVG diagram download.

Keyword Density Analyzer

Analyze keyword usage from a public webpage URL or pasted raw text. The tool fetches page text in URL mode, accepts direct content in text mode, then reports total words, unique words, readability, and top one-, two-, and three-word phrase densities.

Redirect Checker for Public URL Chains

Schema.org (JSON-LD) Generator

Create copyable starter JSON-LD for Article, Product, Event, Organization, Local Business, and Person pages from a browser-side form.

SERP Simulator

Preview a Google-style search snippet from a title, URL, meta description, optional date, and desktop or mobile layout.

Hreflang Generator

Create copy-ready HTML hreflang tags from URL and language rows. The Hreflang Generator runs in the browser, supports one optional <code>x-default</code> row, skips blank URL rows, defaults blank language fields to <code>en</code>, and leaves URL, language-code, reciprocal-link, canonical, sitemap, and HTTP-header validation to your own review.

Canonical URL Generator

Create a copy-ready canonical link tag from a URL you provide. The Canonical URL Generator runs as a browser-side Alpine component, trims outer whitespace, strips embedded tabs and line breaks, escapes HTML attribute characters, and outputs one <code><link rel=\canonical\></code> snippet for manual review and implementation.

Keyword Cloud Density Checker

Fetch a public webpage URL and visualize the most frequent readable content words as a weighted keyword cloud. The tool removes common page chrome, scripts, stop words, short terms, and numeric-only tokens before showing up to 50 repeated content words with counts.

Sitemap Visualizer for Public XML Sitemap Review

Parse a public XML sitemap URL and review its declared sitemap or URL rows in a readable table. The Sitemap Visualizer fetches one public HTTP or HTTPS sitemap, rejects private and local network targets, disables automatic redirects, and reports type, total entries, latest lastmod value, and row-level metadata.

JSON-LD Validator & Auto-Fixer

Validate pasted JSON-LD syntax, check for reachable @context and @type markers across objects, root arrays, @graph documents, and nested nodes, then copy a formatted version or a limited repair suggestion.

PWA Compatibility Checker for Public URL Feature Checks

Check a public HTTP or HTTPS page for visible Progressive Web App markers, including HTTPS, a manifest link, service worker registration hints, viewport metadata, theme color, and iOS app-mode metadata.

PWA Manifest Generator

Create starter manifest.json for a web app in your browser, with editable app names, colors, display mode, orientation, copy, download, and live preview behavior.

AMP Validator

Check a public AMP page URL for common AMP setup requirements. The AMP Validator fetches the submitted page from the server, reviews the returned HTML for required AMP markers, runtime, boilerplate, canonical and viewport tags, and script restrictions, then reports an overall valid, warning, or invalid status.

JSON-LD to Microdata Converter

Convert pasted Schema.org JSON-LD into HTML Microdata. The converter accepts plain JSON-LD or script-wrapped JSON-LD, handles common root objects, root arrays, @graph documents, nested objects, repeated scalar properties, and string or array @type values, then returns copyable HTML for review.

Microdata to JSON-LD

Convert pasted HTML Microdata into formatted JSON-LD for structured data migrations. The tool reads itemscope, itemtype, and itemprop attributes, maps common value attributes, and returns copyable JSON you can review before testing with Schema.org or Google tools.

Robots.txt Generator

Generate a copy-ready robots.txt draft from crawler allow/refuse choices, an optional crawl delay, a sitemap URL, and comma-separated disallowed paths. The Robots.txt Generator runs in the browser, writes output to an Ace editor, and leaves syntax review, crawler support, and final server placement to you.

.htaccess Redirect Generator

Generate basic Apache .htaccess redirect-rule drafts for HTTPS redirects, www or non-www preferences, and simple 301 or 302 redirects. Review the generated mod_rewrite snippet carefully, test it in the real hosting environment, and keep a backup before changing a production .htaccess file.

Htaccess to Nginx Converter

Convert common Apache .htaccess directives into editable Nginx-style snippets in your browser, with an Apache input editor, readonly Nginx output, copy support, and clear unsupported-rule comments for manual review.

HTTP-auth Generator

Generate Apache and Nginx HTTP Basic Authentication snippets, plus server-side htpasswd commands for creating a bcrypt password file. The tool accepts account names, passwords, .htpasswd paths, and realm names, but it does not create a finished production security setup by itself.

GZIP Compression Test

Test a public URL for gzip compression from Digital Domain Kit\u2019s server. See whether the response reports gzip encoding, then review size estimates, compression percentage, HTTP status, request time, content type, and server header.

Domain Generator

Generate available domain name suggestions from a keyword. The tool sends your trimmed keyword to the Verisign suggestion API, checks the API's available results across a fixed set of TLDs, and shows domain rows with buy links built from the configured affiliate URL.

Domain WHOIS

Look up raw WHOIS registration text for a single domain name. The tool normalizes and validates an ASCII domain such as example.com, chooses a WHOIS server from its TLD map, queries port 43, and displays the server response in a copyable textarea.

URL Parser

Parse a complete URL into the exact host, href, path, query string, and hash fragment returned by the browser URL API.

HTTP Headers Parser for First-Response Header Checks

Parse the response headers returned by one public HTTP or HTTPS URL from DigitalDomainKit's server-side vantage point. The HTTP Headers Parser normalizes bare hosts to HTTPS, rejects private and local targets, does not follow redirects, and shows the first response's header lines without downloading the page body.

URL Unshortener

Expand a shortened public HTTP or HTTPS URL by checking its redirect chain from the Digital Domain Kit server. The tool validates the submitted URL and each redirect hop as a public target, blocks private and local destinations, and returns the final public URL when a redirect is found.

HTTP Status Code Checker for Single URL Response Tests

Check one public HTTP or HTTPS URL from the DigitalDomainKit server and see the response as OK, Redirect, Client Error, Server Error, or Unavailable. The checker normalizes bare domains to HTTPS, blocks private or local network targets, uses a simple server-side GET request, and does not follow redirects.

Developer & Data Tools

Validate, inspect, and generate practical web-development output.

HTML Code Editor with Live Preview

Edit HTML in an Ace-powered browser editor and preview the rendered result in a sandboxed iframe. The tool starts with a small sample, updates the preview shortly after you type, and keeps the workflow focused on quick snippet testing rather than file storage or project export.

Regex Tester

Test JavaScript regular expressions in your browser with live match highlighting, capture groups, match indexes, flags, and syntax error reporting.

Cron Expression Generator

Build a standard five-field cron expression from visible minute, hour, day-of-month, month, and weekday fields. Use common presets, edit the fields directly, review the generated expression and plain-language reading, then copy the expression for your own crontab or scheduler configuration.

Markdown to HTML Converter

Convert Markdown into formatted HTML in your browser with Showdown-powered support for tables, task lists, strikethrough, and automatic links.

HTML to Markdown Converter

Paste HTML into an Ace editor and convert it to Markdown in your browser. This DigitalDomainKit tool uses Showdown 2.1.0 with table, task list, strikethrough, and simplified auto-link options enabled, then shows the Markdown in a read-only editor with a copy button.

HTML Minifier

Minify pasted HTML directly in your browser with an Ace editor, a Copy button, and a fixed HTMLMinifier v4.0.0 option set that collapses whitespace, removes comments, shortens common attributes, and minifies inline CSS and JavaScript. Review the rewritten markup before using it in production.

CSS Minifier

CSS Minifier compacts pasted stylesheet code directly in your browser. Paste CSS into the editor, click CSS Minifier, review the rewritten output, and copy the result. It focuses on reducing whitespace and comments where the minifier can, not validating, repairing, prefixing, or fully optimizing your CSS.

HTML Formatter

Paste HTML into an Ace editor and format it in your browser with readable indentation and line breaks. The tool uses the loaded js-beautify HTML formatter, keeps the result in the same editor, and provides a Copy button for moving the formatted markup back to your workflow.

CSS Formatter

CSS Formatter turns pasted stylesheet code into a more readable layout in your browser. Paste CSS into the editor, click Format CSS, then copy the rewritten result with cleaner spacing, indentation, and line breaks. It is a formatting helper, not a CSS validator, fixer, prefixer, optimizer, or minifier.

JSON Beautifier

Format and validate JSON in your browser with readable indentation, optional recursive key sorting, Unicode unescaping, slash cleanup, copy, download, and local `.json` file loading.

Json Validator

JSON Validator checks pasted or uploaded JSON text in your browser and reports whether JavaScript can parse it as valid JSON. Paste a payload, load one of the built-in samples, or read a local `.json` file, then review the validation status, parser error message, byte size, line count, parsed key count, and nesting depth.

URL Encoder

Encode pasted text, query values, or URL fragments with PHP urlencode() on the server. The tool returns a percent-encoded string where spaces become plus signs, reserved characters become %HH sequences, and the result can be copied for query strings, form-style data, tests, or documentation.

URL Decoder

Decode percent-encoded URL text into a readable string using Digital Domain Kit's server-side PHP decoder. Paste an encoded full URL, path, query string, or individual parameter value to convert escape sequences such as %3F, %26, %2F, and %20, with copy support for the decoded result.

Unicode to Punycode

Encode Unicode text into raw Punycode in your browser, then copy the ASCII-compatible result for label testing, IDN research, and encoding comparisons.

Security & Privacy Tools

Review public security signals and privacy-related website settings.

Security Headers Auditor: Check Browser Header Presence

Audit one public HTTP or HTTPS URL for six common browser security headers. DigitalDomainKit validates the target, rejects private and local network destinations, sends one server-side GET request with redirects disabled, then reports weighted header presence, a simple score, and passive WAF/CDN header signals from that single response.

Safe Browsing Checker for Public URL Heuristic Audits

Check a public HTTP or HTTPS URL with a lightweight server-side audit for HTTPS use, HSTS, simple phishing patterns, and clickjacking protection. The checker validates that the target is public, does not follow redirects automatically, and provides vendor lookup links for separate manual review.

SSL Checker for Public Website Certificate Inspection

Inspect the SSL/TLS certificate presented by a public website and review the dates and identity fields the current tool can read. The checker accepts a public HTTP or HTTPS URL, blocks private and local targets before probing, and reports certificate timing, issuer, organization, and common name details when available.

Browser Fingerprint Audit

Run a local browser fingerprint demo that checks visible browser, screen, hardware, canvas, and audio signals in your browser.

Public IP and VPN Visibility Check

Check what public IP address and location hints your browser exposes to browser-accessible diagnostic services. This legacy DNS leak tester page now reports public connection visibility only; it does not perform resolver-specific DNS leak testing or identify the DNS servers used by your VPN, browser, router, or operating system.

Network Tools

Investigate DNS, HTTP, IP, and public network information.

Subdomain Finder

Find publicly indexed subdomains for a domain using HackerTarget host search results.

WebRTC Leak Test

Run a browser-side WebRTC ICE candidate check and see whether the current browser exposes public or local IP-style addresses through peer connection discovery. The tool uses RTCPeerConnection with public STUN servers and separates detected public-looking addresses from private LAN ranges.

Website Status Checker for Public URL Availability Tests

Check a public website or URL from the DigitalDomainKit server and see whether the response is OK, Redirect, Client Error, Server Error, or Unavailable. The tool normalizes bare domains to HTTPS, validates public HTTP(S) targets, uses a server-side GET request, and does not follow redirects.

Hostname to IP Lookup

Resolve a hostname or domain to its current IPv4 A-record addresses from the DigitalDomainKit server, with copyable results and optional location and network details for the first resolved IP.

User Agent Finder

Find the user-agent string and basic request-header details your browser sends to DigitalDomainKit, including parsed browser, operating system, device, bot, language, and platform fields.

Whats My IP

Show the public IP address visible from your current browser request, then review related location and network lookup fields such as country, region, city, ISP, ASN, timezone, coordinates, currency, and calling code when the lookup provider returns them.

DNS Lookup Tool

Look up public DNS records for a domain or URL and review A, AAAA, MX, NS, SOA, and TXT results in a copy-friendly format.

ASN Lookup

Look up an Autonomous System Number or public IP address and review the ASN, organization, registry status, registration date, or IP network context returned by the live lookup providers.

Traceroute Online: Public Route-Hop Diagnostic From a Server Vantage Point

Trace the route toward a public domain or IP address from the DigitalDomainKit server, or from the configured fallback traceroute service when local probing is unavailable. The tool validates public targets, resolves hostnames, probes up to 20 hops, and reports hop numbers, hostnames, IP addresses, and latency-like timing when routers respond.

Email Blacklist Check

Check a required email address by looking up its domain and resolved mail-server IPv4 addresses against common DNSBL and domain blacklist zones from Digital Domain Kit's server.

DNS Propagation Check

Check a domain against selected DNS-over-HTTPS resolvers and compare returned A, AAAA, MX, CNAME, TXT, NS, or SOA records as results stream in one resolver at a time. The tool validates a hostname and record type, queries public resolvers server-side, and may fall back to local DNS resolution when remote checks fail.

Website Technologies Check

Check a public website from Digital Domain Kit's server to review likely technologies, server headers, DNS/hosting signals, SSL certificate dates, compression, protocol hints, and basic security-header presence.

From our guides

The latest practical guides from the Digital Domain Kit editorial team.

Oct 28, 2026

How to Review HTTP Security Headers After a Website Launch

Check the headers your live pages actually send, understand what each policy protects, and change CSP or HSTS without breaking the site.

Oct 26, 2026

SSL Certificate Valid but Browser Says Not Secure? Check the Actual Page and Hostname

A valid certificate for one host does not secure every page load. Separate HTTP navigation, hostname mismatch, and mixed content with a short browser-first workflow.

Oct 24, 2026

Google Chose a Different Canonical? Diagnose the Signals Before Changing the Tag

Search Console may show a different canonical than the one you declared. Compare both URLs, resolve conflicting signals, and decide whether a change is needed.

Oct 22, 2026

How to Verify a Cron Job Really Ran and Diagnose a Missed Schedule

Trace a scheduled task from its due time through process exit and the expected result, then diagnose missed runs without guessing.