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DNS

DNS LookupDig-style lookup for A, AAAA, MX, TXT, NS, SOA, SRV, CAA, PTR — plus subdomain sweep. DNS PropagationQuery one record across Google, Cloudflare, Quad9 and OpenDNS to spot propagation lag. WHOIS LookupRegistration, registrar, dates and nameservers for a domain (live WHOIS).

Email

SPF CheckerFetch and validate a domain's SPF record, with the 10-lookup limit in mind. DMARC CheckerRead and explain a domain's DMARC policy (p, rua, pct, alignment). DKIM CheckerLook up a DKIM public key by selector and domain. MX LookupList a domain's mail servers in priority order. Blacklist CheckCheck an IP against major DNS blacklists (RBLs). Email VerifierValidate an address: syntax, domain MX, role/disposable, live mailbox probe. Email Header AnalyzerPaste raw email headers to trace delivery hops and delays.

Network

SSL CertificateInspect a site's TLS certificate: issuer, validity, SANs and expiry. HTTP HeadersView a URL's response headers and follow its redirect chain. Security HeadersGrade a site on HSTS, CSP, X-Frame-Options and other security headers. Port CheckerTest whether common or custom TCP ports are open on a host. IP InfoReverse DNS plus ASN, network and country for an IP (via Team Cymru).

Encoding

JWT DecoderDecode a JSON Web Token to read its header and payload claims. HMAC GeneratorCompute an HMAC (SHA-256/512, SHA-1, MD5) from a key and message. Base64Encode or decode Base64 text. URL Encode/DecodePercent-encode or decode URL/query strings. Hash GeneratorMD5, SHA-1, SHA-256, SHA-512 and CRC32 of any text. JSON FormatterPretty-print, validate or minify JSON. Punycode / IDNConvert internationalized domains between Unicode and punycode (xn--).

Dev

Regex TesterTest a regular expression against sample text and see the matches. Password StrengthEstimate how strong a password is: entropy and crack-time. Bcrypt Hash & VerifyGenerate a bcrypt password hash, or verify a password against one. Cron ExplainerTranslate a cron expression into plain English and list its next run times. UUID GeneratorGenerate random UUID v4 values in bulk. Password GeneratorCreate strong random passwords with adjustable rules. Subnet CalculatorIPv4 CIDR maths: network, broadcast, mask, host range and count. Epoch ConverterConvert between Unix timestamps and human dates.

Text

Color ConverterConvert colours between HEX, RGB and HSL with a live preview. Case ConverterConvert text between UPPER, lower, Title, camelCase, snake_case and kebab-case. HTML Entity EncoderEncode or decode HTML entities like & and ©. Number Base ConverterConvert numbers between binary, octal, decimal and hexadecimal. Text CompareCompare two blocks of text and highlight the differences line by line. Word CounterCount words, characters, sentences, paragraphs and reading time. SlugifyTurn a title into a clean, URL-friendly slug. Lorem IpsumGenerate placeholder Lorem Ipsum paragraphs, sentences or words.

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Free DNS, email, network & developer utilities. No accounts, no tracking, nothing stored.

DNS & Domain

DNS Lookup DNS Propagation WHOIS Lookup

Email & Deliverability

SPF Checker DMARC Checker DKIM Checker MX Lookup Blacklist Check Email Verifier Email Header Analyzer

Network & Security

SSL Certificate HTTP Headers Security Headers Port Checker IP Info

Encoding & Data

JWT Decoder HMAC Generator Base64 URL Encode/Decode Hash Generator JSON Formatter Punycode / IDN

Developer Tools

Regex Tester Password Strength Bcrypt Hash & Verify Cron Explainer UUID Generator Password Generator Subnet Calculator Epoch Converter

Text & Conversion

Color Converter Case Converter HTML Entity Encoder Number Base Converter Text Compare Word Counter Slugify Lorem Ipsum

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