host
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tools
DNS
DNS
Records, propagation, trace, DNSSEC, zone transfer
DNS lookup (dig)
Query A, AAAA, MX, TXT, CNAME, NS, SOA, SRV, CAA, PTR — all types at once.
DNS propagation
Query 15 global resolvers — see if your DNS change has propagated worldwide.
Reverse DNS (PTR)
Find the PTR / hostname for an IPv4 or IPv6 address.
DNS chain trace
Walk the resolution chain: TLD → authoritative NS → final answer.
Wildcard detector
Detect catch-all wildcard records on a domain.
Zone transfer (AXFR) test
Check whether your authoritative name servers leak the full zone via AXFR.
DNSSEC validator
Check the DS / DNSKEY chain to see whether DNSSEC is signed for a zone.
IP
IP
Geolocation, WHOIS, ASN, reverse, subnet calc
ASN lookup
Resolve an IP or AS number to its autonomous system, prefixes, country.
IP geolocation
Country, region, city, ASN, org, timezone, abuse contact for any IP.
Reverse IP / hosted domains
Find other domains that resolve to the same IP.
Subnet / CIDR calculator
Network, broadcast, host range, mask, wildcard, hex, binary, total hosts.
IP type detector
Datacenter, residential, mobile, Tor, VPN or proxy classification.
IP WHOIS
Direct port-43 WHOIS at the appropriate RIR (ARIN, RIPE, APNIC, LACNIC, AFRINIC).
My IP
Show your public IPv4/IPv6 with geolocation and ASN.
Domain
Domain
WHOIS, availability, IDN, TLD info, subdomains
Domain availability
Check if a name is available across 20+ popular TLDs.
Punycode / IDN converter
Convert internationalised domain names to/from xn-- ASCII form.
Domain WHOIS
Registrar, dates, name servers, contacts, DNSSEC status.
Subdomain enumerator
Discover subdomains via Certificate Transparency logs (crt.sh).
SSL/TLS
SSL/TLS
Certificate info, chain, HSTS, expiry
HSTS preload check
Is your domain on the Chromium HSTS preload list?
SSL certificate inspector
Issuer, SAN, validity, fingerprints, full chain — for any TLS endpoint.
HTTP
HTTP
Headers, security headers, redirects, robots, sitemap
Hreflang validator
Find every <link rel="alternate" hreflang="…"> on a page and validate it.
HTTP headers
Capture every response header, follow redirects, time each hop.
OpenGraph & Twitter Card preview
Preview how your URL looks when shared on Facebook, Twitter, LinkedIn, Slack.
Page weight & timing
Real-network fetch with full timing breakdown — DNS / connect / TLS / TTFB / total / payload size / compression.
Redirect chain tracer
Step-by-step view of every redirect with status, latency and location.
robots.txt parser
Fetch and parse robots.txt — User-agent groups, Disallow/Allow, Sitemap, Crawl-delay.
Schema.org validator
Pull JSON-LD blocks from a page and validate the @type / required fields.
Security headers grader
A+ to F grade for HSTS, CSP, X-Frame-Options, COOP, Referrer-Policy and more.
sitemap.xml inspector
Fetch and parse sitemap or sitemap-index, list URLs with lastmod, priority.
HTTP status check
Quick, single-shot status code + content-type for any URL.
Tech stack detector
CMS, framework, server, CDN, analytics fingerprints.
URL inspector (GSC-style)
Indexability, canonical, robots, hreflang, schema, security — all in one.
.well-known inspector
Probe RFC 8615 .well-known files: security.txt, change-password, openid, mta-sts, etc.
Email
Email
MX, SMTP, SPF, DKIM, DMARC, blacklists
Email blacklist (RBL) check
Query 16+ public RBLs in parallel — Spamhaus, Barracuda, Spamcop, SORBS, more.
DKIM tester
Look up DKIM keys for any selector. Auto-tries common selectors.
DMARC tester
Parse the DMARC record, classify policy, list aggregate/forensic recipients.
Email auth all-in-one
SPF + DKIM + DMARC + BIMI + MTA-STS + TLS-RPT in a single shot.
MX lookup
Resolve mail-exchange records, sort by priority, banner-test SMTP.
SMTP test
Connect, EHLO, STARTTLS, capture banner & supported extensions.
SPF tester
Inspect, validate, expand a domain's SPF record. Lookup-budget aware.
Network
Network
Ping, traceroute, port scan, multi-region live checks
Multi-region HTTP availability
TTFB, status, redirect chain from each region.
Multi-region ping
Ping from probe nodes worldwide. Streams per region.
Multi-region TCP port check
Open / closed / filtered status of any TCP port from each region.
Port scanner
Probe the most-common 20 service ports — or a custom list.
Traceroute (live)
Stream every hop with RTT — Windows tracert / Linux traceroute under the hood.
Security
Security
Cookies, CORS, CSP analyser
Cookie audit
Inspect Set-Cookie headers — Secure / HttpOnly / SameSite / domain / path.
CORS tester
Probe Access-Control-* headers from a chosen Origin & method.
Encoders
Encoders
Base64, URL, HTML entities, hash, HMAC, JWT, data: URI
Base64 encode / decode
Standard and URL-safe Base64 in both directions.
Hash & checksum
MD5, SHA1, SHA224, SHA256, SHA384, SHA512, CRC32, BLAKE2 — for any text.
HMAC generator
HMAC-SHA1/256/512 of any text with any key.
HTML entities ↔ text
Encode special characters to entities, or decode them back.
Image → data: URI
Fetch an image from URL and base64-encode it as a data: URI for inlining.
JWT decoder
Decode header, payload, signature. Show alg, typ, claims, expiry status.
URL encode / decode
percent-encode + parse a URL into scheme, host, path, query.
Generators
Generators
Passwords, UUIDs, QR, lorem, .htaccess, robots, sitemap, CSP, htpasswd
CSP header builder
Build a Content-Security-Policy from sane defaults — strict, modern, copy-paste ready.
.htaccess generator
Generate .htaccess for HTTPS redirect, www canonicalisation, gzip, headers, hotlink block.
.htpasswd generator
Apache htpasswd hashes (bcrypt, SHA, APR1) for any user/password.
Lorem ipsum generator
Filler text in paragraphs, sentences, words or list items.
Password generator
Strong passwords with adjustable length, charset, entropy meter.
QR code generator
Generate a QR code for any URL or text — PNG/SVG download.
robots.txt generator
Generate a robots.txt with sensible disallows, sitemap declaration, optional bot blocks.
sitemap.xml generator
Build a sitemap.xml from a URL list. Supports lastmod, priority, changefreq.
UUID generator
Generate UUID v4 / v7 / nil. Decode UUIDv1 timestamp.
Converters
Converters
JSON / YAML / CSV, color, case, number-base, timestamp, markdown
String case converter
camelCase, snake_case, kebab-case, PascalCase, SCREAMING_SNAKE, Title Case, sentence case.
Color converter
HEX ↔ RGB ↔ HSL ↔ HSV ↔ CMYK with on-the-fly preview.
CSV ↔ JSON
Auto-detect and convert CSV to JSON, or JSON to CSV. Handles quoted fields, custom delimiters.
JSON formatter / validator
Pretty-print, validate, minify JSON. Reports the exact error position.
Markdown ↔ HTML
Render markdown to safe HTML, or strip HTML tags back to plain markdown.
Number base converter
Convert between binary, octal, decimal, hex (base 2 / 8 / 10 / 16) plus arbitrary base.
Unix timestamp converter
Unix epoch ↔ ISO 8601 ↔ RFC 2822, multiple timezones.
YAML ↔ JSON
Convert between YAML and JSON. Auto-detects direction.
Text
Text
Diff, regex, text stats, slug
Regex tester
Test PCRE patterns, capture groups, named captures and replacement.
Slug generator
URL-safe slugs from any text — handles unicode, whitespace, casing.
Text diff
Line-by-line diff between two text blocks. Insertions, deletions, unchanged.
Text & word counter
Characters, words, sentences, lines, reading time, byte length.
Reference
Reference
HTTP status codes, well-known ports, User-Agent, MAC OUI, cron
Cron expression parser
Translate cron syntax to plain English and preview the next 10 fire times.
HTTP status code reference
Quick reference for every HTTP status — 100 to 599. RFC reference + safe to retry.
MAC address / OUI lookup
Identify the manufacturer behind a MAC address (first 24 bits = OUI).
Well-known ports reference
TCP/UDP service-port reference. Lookup a number, see the protocol.
User-Agent parser
Parse User-Agent strings — browser, engine, OS, device, bot detection.
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Security
Security tools
Cookies, CORS, CSP analyser
Inspect
Cookie audit
Inspect Set-Cookie headers — Secure / HttpOnly / SameSite / domain / path.
CORS tester
Probe Access-Control-* headers from a chosen Origin & method.