Free Tools

Uptime Calculator

Calculate uptime in seconds, minutes, hours, and days based on the uptime percentage you enter.

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Downtime Calculator

Calculate downtime in seconds, minutes, hours, and days based on the uptime percentage you enter.

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SLA Calculator

Use this calculator to see whether your uptime percentage meets your SLA goals.

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DNS Checker

Check DNS propagation and look up A, AAAA, MX, NS, CNAME and TXT records from 14 locations across 6 continents.

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Domain Checker

Look up any domain: WHOIS/RDAP record, expiry date, registrar, nameservers and EPP status codes, with a plain-English verdict.

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WHOIS Checker

Look up any domain or IP: the raw WHOIS/RDAP record decoded into plain English — who owns it, how old it is, an ownership-history hint and the IP behind it.

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SSL Checker

Check any SSL/TLS certificate: expiry, chain, hostname coverage and protocol support, with a plain-English verdict.

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TLS Version Checker

Check which TLS/SSL protocol versions a site accepts — SSL 3.0 to TLS 1.3 — plus its cipher suites, with a plain-English verdict.

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Website Availability Test

Use this tool to check whether your website is reachable from 30+ locations worldwide.

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Is It Down?

Check if a website is down for everyone or just you.

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Ping Test

Ping any host or IP from 14 locations worldwide — latency, jitter and packet loss per route.

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Page Speed Test

Test any page's load speed in a real Chrome browser — desktop and 4G mobile — with milestones in seconds, Core Web Vitals and a fix list ranked by seconds saved.

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Website From Country

Load any URL from 14 countries across 6 continents at once and see whether every country gets the same site — or a geo-wall, redirect or different CDN edge.

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Blacklist Checker

Check a domain, IP or mail server against 17 blocklists — Spamhaus, Barracuda, SpamCop and more, plus Google Safe Browsing.

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HTTP Status Checker

Check any URL's status code, follow every redirect hop by hop, and decode the response headers.

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HTTP Protocol Checker

Check any site for HTTPS enforcement, HTTP/2 (and HTTP/3), HSTS and real IPv6 — scored 0–4.

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SPF Record Checker

Parse any domain's SPF record: every include expanded, all 10 DNS lookups counted, the all policy graded.

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DKIM Checker

Find and grade any domain's DKIM key: selector auto-discovery, the p= key decoded and measured, testing flags and revoked tombstones called out.

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DMARC Analyzer

Grade any domain's DMARC policy on what it actually blocks: p=none is monitoring, not protection. Every report destination is checked for authorization too.

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MTA-STS Checker

Read both halves of a domain's MTA-STS setup — the DNS pointer and the HTTPS policy over a valid certificate — then match every mx: pattern against the live MX, the check that catches self-inflicted mail outages.

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TLS-RPT Checker

Validate a domain's TLS reporting record, then probe every rua destination with a real POST instead of trusting its syntax — and check whether an MTA-STS or DANE policy exists for those reports to describe.

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BIMI Checker

Check BIMI in the order providers do: the DMARC gate first, then the default._bimi record, the SVG linted against every Tiny PS clause, and the mark certificate decoded — its embedded logo byte-compared to the served file.

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MX Lookup

List a domain's MX records by priority, resolve every host, run the FCrDNS round trip receivers score, fingerprint the provider — then connect on port 25 from our probes and test STARTTLS live.

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Port Checker

Knock on the common ports of a host you're responsible for and get open, filtered or closed — then the reading: web ports that should answer, admin ports that belong behind a VPN, databases that should never face the internet.

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Subnet Calculator

Network and broadcast, first and last usable host, the mask in every notation and the seam drawn in binary — for IPv4 and IPv6 in one box, plus a VLSM planner. The maths runs in your browser, so nothing you type is sent anywhere.

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Find IP of a Website

Resolve a domain to its IPv4 + IPv6 addresses, walk reverse DNS both directions, name the network owner from the routing registries — and get the map dot labeled as the guess it is.

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What Is My IP

Your public address as every website sees it, with your ISP's network, your reverse DNS name and a location estimate labeled for what it can and cannot pin down. No lookup history kept.

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Traceroute

Walk the path to any host hop by hop: every router named and attributed to its network, a geolocated route map, real bottlenecks told apart from lazy routers — and a TCP knock when the trace goes dark.

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Security Headers Checker

One letter grade for every security header your site sends — HSTS, CSP, frame protection, nosniff and every cookie flag, values analyzed instead of box-ticked, with copy-paste nginx, Apache and Cloudflare fixes ordered by points gained.

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Cron Expression Generator

Generate a cron expression by typing in plain English.

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Cron Expression Descriptor

Enter a cron expression and we'll describe when it runs in plain English.

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Cron Expression Examples

Browse ready-to-copy cron expressions for the most common schedules.

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