DNS Lookup - Online Domain Records Checker (A, MX, CNAME)
Query DNS records for any domain directly from your browser using DNS-over-HTTPS. See A, AAAA, MX, CNAME, and TXT records. No logs.
UD5 Toolkit
Check DNS record status across multiple global resolvers in real time.
| DNS Resolver | Status | Record Data | Consistency |
|---|
Query DNS records for any domain directly from your browser using DNS-over-HTTPS. See A, AAAA, MX, CNAME, and TXT records. No logs.
Create a CAA DNS record to specify which certificate authorities can issue SSL certs for your domain. Prevent mis‑issuance.
Enter a URL and a user‑agent to see if it is allowed or blocked by the robots.txt file. Quick bot validation.
Check if your site is cross‑origin isolated by examining the COOP and COEP headers. See if SharedArrayBuffer is available.
Inspect any website's SSL/TLS certificate details: issuer, expiry date, subject, and SANs. Verify certificate chains. All checks are private and require no server upload.
Create a DMARC policy record with percentage, reporting addresses, and alignment mode. Validate and copy the final DNS TXT.
Check if an IBAN has the correct length and structure for its country. Early validation, no bank connection.
Enter a URL and see its CORS headers. Understand why a fetch fails. Check preflight responses. Client‑side debugger.
Search a complete list of all top‑level domains. See which still have availability. For brand naming. Static reference.
Validate ISBN‑10 and ISBN‑13 numbers and compute their check digits. Useful for booksellers and libraries. All local.
Paste N‑Triples data and convert it to a compact JSON‑LD representation. Work with linked open data. Local.
Simulate reduced motion preference and test your animations. Copy the media query snippet. Keep your users safe.
Paste raw email headers and see authentication results (SPF, DKIM, DMARC) in a readable table. Find spoofing attempts.
Paste raw email headers and get a human-readable breakdown of the delivery route, authentication results, and delays. Private analysis.
Detect browser support for font‑tech() and font‑format() values in @font‑face src. Check COLRv1, variable, etc.
Paste HTML and see the order in which elements would receive focus via Tab key. Highlight issues. Local accessibility testing.
Paste a `Set‑Cookie` header and see all attributes parsed: domain, path, Max‑Age, SameSite, Secure, HttpOnly. Debug cookies easily.
Paste your JSON‑LD or Microdata and test it against Google's Rich Results criteria. Get warnings. Local linter.
Patch the PerformanceObserver and show your page’s Core Web Vitals as you browse. See real‑time scores and suggestions.
Turn a cardinal number (23) into its ordinal form (23rd). Supports large numbers. Simple and quick.
Check and beautify your TOML config files. Highlights errors and aligns tables and arrays. Safe local parsing.
Drop an image that might have wrong extension and see its real format (JPEG, PNG, WebP) based on header bytes.
Translate text into semaphore flag positions and decode semaphore back to letters. Interactive animated flags. For scouts and maritime fans.
Search for any file extension to see its full name, MIME type, and description. Covers thousands of entries. Static data.
Enter an acronym and see its most common full forms. Static dictionary. No internet needed after load.
Test how non‑Latin characters (Chinese, Cyrillic, Arabic) convert to URL‑safe slugs with proper transliteration rules. Preview the final string.
Identify common grammar mistakes (subject-verb agreement, tense, articles) with simple rule-based analysis. Explanations provided. Not AI, purely rule-based and local.
Check English spelling and get suggestions using the browser's built-in dictionary. Highlight errors instantly. No data leaves your machine.
Normalize text to any Unicode normalization form to prevent encoding bugs and ensure consistent comparison. Essential for i18n developers.
Create a temporary chat room between two browser tabs or devices on the same network using WebRTC data channels. Copy the code.