A curated collection of ten free network tools for looking up IP addresses and geolocation, testing latency and connection speed, querying DNS and WHOIS records, checking SSL certificates, and calculating subnets. All free, browser-based, no signup.
This is the Zovo collection of free network tools, a single hub that gathers the utilities you reach for when something on a network is slow, broken, or simply unknown. Instead of one heavyweight suite, each tool does one job well: looking up the location and owner of an IP address, measuring the latency and download speed of your connection, querying the DNS records behind a domain, reading WHOIS registration details, inspecting an SSL certificate, explaining a wall of HTTP headers, or calculating subnets and CIDR ranges. Together they cover the lookup, diagnosis, and calculation chores that come up whenever you are working with networks.
The collection is built for network engineers, sysadmins, developers, support technicians, students studying for certifications, and anyone who just wants to understand why a site will not load or a connection feels slow. Whether you are tracing where a request is going, confirming that a domain points where it should, planning an address scheme for a new subnet, or checking that a certificate has not expired, these tools turn a fiddly task into a paste-and-read or one-click operation. Each one is focused enough to learn in seconds and reliable enough to keep in a pinned tab.
Every tool here is completely free with no trial, no credit card, and no premium tier hiding the useful parts, and none of them require an account or signup, you open a tool and start working immediately. They are all browser-based: the calculators run entirely on your device, while the lookup tools query public data providers for the IP, DNS, WHOIS, and certificate details they show. One thing worth knowing up front is that the diagnostic tools are real, not simulated: the Ping Test and Internet Speed Checker send actual network requests from your browser to public endpoints and time the round trips, so the numbers reflect the connection you are sitting on right now rather than a canned figure. Pick a tool below, or read the workflow section to see how they chain together.
Find out who and where an IP address belongs to, or detect your own.
Look up any IP address to find its geolocation, ISP, organization, and timezone, auto-detect your own IP, and run bulk lookups. Free and private.
Open tool →Detect your IP, ISP, location, timezone, and coordinates, and look up any IPv4 or IPv6 address with geolocation and DNS information.
Open tool →Measure how your connection is actually performing right now, from your own browser.
Measure network latency, jitter, and connection quality in real time by pinging multiple CDN endpoints, with live charts. Runs from your browser.
Open tool →Run a real internet speed test from your browser to measure download throughput, with instant results and no registration required.
Open tool →Resolve the records and ownership details behind any domain name.
Query A, AAAA, CNAME, MX, NS, TXT, and SOA records for any domain using Google DNS-over-HTTPS, with bulk lookup, TTL display, and query times.
Open tool →Look up WHOIS information, DNS records (A, AAAA, MX, TXT, NS, CNAME), and domain details instantly, with free DNS-over-HTTPS and bulk domain checking.
Open tool →Inspect certificates and headers, and plan address space with precise subnet math.
Check SSL/TLS certificates for any domain, verify HTTPS availability, HSTS headers, and HTTP-to-HTTPS redirects, with a TLS reference guide.
Open tool →Paste raw HTTP headers to instantly parse, categorize, and explain every one, covering security, caching, CORS, and content headers.
Open tool →Calculate network address, broadcast, subnet mask, wildcard mask, CIDR notation, and VLSM subnetting for IPv4 and IPv6, entirely in your browser.
Open tool →Break down addresses with subnet calculations, a VLSM calculator, IPv4-to-IPv6 mapping, CIDR aggregation, and binary representation.
Open tool →Most network problems get solved by working outward from "where is this going?" to "why is it failing?", and this collection maps onto that path. When you only have an address, start by giving it an identity: the IP Lookup and the IP Address Tracker turn a bare IP into a location, ISP, and organization, and they will also auto-detect the public IP your own connection is using, a quick way to confirm what the outside world sees you as.
If the connection itself feels wrong, measure it instead of guessing. The Ping Test sends real requests from your browser to multiple endpoints and reports latency and jitter, which tells you whether the link is stable, while the Internet Speed Checker measures actual download throughput so you can compare it against the speed you are paying for. Because both run on your device, the numbers describe the connection you are on, not a server somewhere else.
When a site will not load at all, drop down to name resolution and ownership. Query the domain's records with the DNS Lookup to see whether its A, AAAA, MX, and NS records resolve and what their TTLs are, and pull registration and DNS details together with the WHOIS Lookup to confirm who owns the domain and where it is pointed. If the page loads but the browser complains about security, inspect the certificate with the SSL Certificate Checker to verify HTTPS, HSTS, and redirects, then read the response headers with the HTTP Header Analyzer to understand the security, caching, and CORS directives the server is sending.
The final group is for planning rather than diagnosing. When you are designing or documenting an address scheme, the Subnet Calculator works out the network address, broadcast, mask, and CIDR ranges for IPv4 and IPv6, and the IP Address Calculator adds VLSM breakdowns, CIDR aggregation, IPv4-to-IPv6 mapping, and binary views. Identify the address, measure the link, resolve the name, inspect the security, then plan the space, a full troubleshooting loop without leaving your browser.
If you are not sure where to begin, match your goal to a tool:
Yes. Every tool in this collection is completely free to use with no trial, no credit card, and no hidden upgrade wall. There are no usage limits and no premium tier that locks the useful features. We build them as genuinely useful utilities, supported by the rest of the Zovo site, so you can look up an IP, run a ping test, query DNS, check a certificate, or calculate a subnet without paying anything.
No. There is no account, no signup, and no login. You open any tool and start working immediately. Most of these tools run in your browser, and the few that need external data query a public service directly, so there is nothing to register and no profile to manage.
They run from your browser. The Ping Test and Internet Speed Checker measure latency, jitter, and throughput by sending real network requests from your own device to public endpoints and timing the round trips. Because the measurement happens on your machine, the numbers reflect the actual connection you are sitting on right now, not the path between some distant server and a test host. Closing the tab stops the requests.
Match the tool to the symptom. To find out who and where an address belongs to, use the IP Lookup or the IP Address Tracker. To measure whether the connection itself is slow or unstable, run the Ping Test for latency and jitter and the Internet Speed Checker for download throughput. If a site will not resolve, query its records with the DNS Lookup and check ownership with the WHOIS Lookup. If a secure site shows certificate warnings, inspect it with the SSL Certificate Checker, and use the HTTP Header Analyzer to read the response headers.
The tools that calculate values, such as the Subnet Calculator and IP Address Calculator, run entirely in your browser and send nothing anywhere. The only external request on the page itself is a standard Google Analytics page-view tag. The lookup tools, by design, must send the IP or domain you enter to a public data provider so they can return geolocation, DNS, WHOIS, or certificate information, and the ping and speed tests contact public endpoints to measure timing. Those requests go to the data source or endpoint, not to a Zovo account tied to your identity.