Free tools
Sixteen tools that answer straight away, with no account and nothing to install. They are the same checks Expansel runs continuously, available here one at a time.
The essentials
Check the links on a page
Every external link on a page tested, and each link classified followed, nofollow, sponsored or ugc.
Does this page send readers to dead ends?Check redirects
The whole redirect chain, hop by hop, with the type of each one.
Where does this address really lead?Check a backlink
Whether the link is there, with which anchor, dofollow or nofollow.
Does this site link to mine?Is this site down?
Does the site answer, from our server and from another connection? With the cause when it does not.
Down for everyone, or just me?Check a domain name
Expiry date, registrar and status of a domain name.
When does this domain expire?Check SPF, DKIM and DMARC
SPF, DKIM and DMARC read and assessed, including the chain of ten SPF lookups, with the Gmail and Yahoo requirements.
Why do my emails land in spam?Domain age
How long a domain has existed, according to the registry and to the Internet Archive, and whether it changed hands.
How old is this domain?SEO and search engines
Can my page be indexed?
Noindex, robots.txt, canonical, HTTP status: what stops Google and Bing from indexing a page, engine by engine.
Why is my page not indexed?Test the robots.txt
Whether the site robots.txt allows this address to be crawled.
Is my page blocked?Robots.txt generator
A robots.txt written for your site, AI crawlers included, tested before it goes live.
What goes in my robots.txt?Google and social media preview
Your title and description as Google, Bing, Facebook, LinkedIn, X and WhatsApp will show them, measured in pixels.
Will my title be cut off?The site: technology, host, domain
What CMS is this site using?
The CMS, the shop, the WordPress theme and the tools a page gives away, with the proof for each.
What is this site built with?Who is hosting this website?
Who hosts the pages, who runs the DNS and who handles the email, without mixing them up.
Where is this site hosted?DNS propagation
What the domain's own server and six public resolvers answer, and how long until all of them see the change.
Has my DNS change propagated?Security
Check an SSL certificate
Certificate expiry date, issuer, and the names it actually covers.
How many days until it breaks?Check security headers
HSTS, CSP, X-Frame-Options and the rest: a score out of 100, with the scale and the raw headers.
Is my site properly protected?Which one to use, depending on what you are after
These tools answer different questions, and half the time lost comes from opening the wrong one. Here is the mapping.
| The symptom | The tool |
|---|---|
| A site no longer opens and you do not know whether it is on your side | Is this site down? |
| A page does not show up in Google and you do not know why | Can my page be indexed? |
| You are writing a title and want to know whether it will be cut | Google and social media preview |
| You want to know whether robots.txt blocks an address, or whether it is well written | Test the robots.txt |
| You need to write a robots.txt, or decide what to do about AI crawlers | Robots.txt generator |
| A page sends visitors to 404 errors | Check the links on a page |
| A page takes a long time to load for no reason | Check redirects |
| A partner says they placed a link to you | Check a backlink |
| You just changed a DNS record and are waiting for it to be seen everywhere | DNS propagation |
| Your emails land in spam, or Gmail rejects them | Check SPF, DKIM and DMARC |
| You want to know what a site is built with | What CMS is this site using? |
| You are looking for who hosts a site, its email or its DNS | Who hosts this site? |
| You want to know how long a domain has existed | Domain age |
| You want to know when a domain expires | Check a domain name |
| The browser shows a security warning | Check an SSL certificate |
| An audit flags missing security headers | Check security headers |
When a one-off tool is no longer enough
These tools answer a question asked at a given moment. That is exactly what you need when you are looking for the cause of a problem you have already noticed, or preparing a page before publishing it.
The trouble lies elsewhere: most incidents go unnoticed. A certificate expires on a Sunday, a partner removes a link during a redesign, a deployment leaves one line too many in robots.txt. Nobody warns you, and the question only occurs to you weeks later, while looking for why traffic dropped.
The practical rule is simple: if you ask yourself the question once, a tool is enough. If you should ask it every week and you will not, something has to ask it for you.
What none of these tools does
- They do not monitor anything over time. Every check is a one-off, and nothing is kept between visits.
- They do not crawl a whole site. They work on one address at a time, and the page-links tool stops at the first twenty-five links.
- They do not replace Search Console. They read what any visitor can read, with no privileged access to your search data.
Frequently asked questions
Do I need an account?
No, none at all. These pages work with no sign-up, no email address and no card. They exist because they are useful, and the product only shows up once we have answered you, never before.
Is there a usage limit?
Yes, a reasonable number of checks per hour, lower for the tool that tests the links on a page since that one makes up to twenty-five requests on its own. Without that cap, a free page open to everyone would become a convenient way to fire thousands of requests at any site from our server.
What happens to the addresses I type?
We keep the domain name you type, to feed our domain registry, along with the result of the check, which lets us answer straight away if the same request comes back. The content of the pages we fetch is never kept, and your IP address is only kept as a fingerprint, to spot abuse.
These checks, continuously, on all your sites
Expansel runs these checks on a schedule and writes to you when something changes. Free for one site and ten links, no card required.