Free website analysis: what you can check for free, and the limits

Free website analysis covers more than you think: DevTools, webmaster panels, PageSpeed, the terminal and scanners. Where the limits are and when to pay.

SEO · Published: 10 October 2026 · 5 min read · Дмитрий Орлов

"Free" usually sounds like "superficial", yet a surprising amount of website analysis costs nothing at all. Browsers ship professional tools, search engines publish data about your own site, and a terminal answers in seconds what a consultant would bill an hour for. The catch is not the quality of free tools — it is that each one sees a different slice, and none of them watches the site for you. Here is what a free website analysis can cover, with which kinds of tools, and where paying starts to make sense.

1. The browser: DevTools and Lighthouse

Every Chromium browser and Firefox has developer tools built in. In ten minutes on one page you can see:

• Console — JavaScript errors and failed requests; why they matter is explained in our article on console errors;
• Network — status codes, redirects, response sizes, whether files are compressed and cached;
• Lighthouse — a lab run of performance, accessibility, SEO and best practices.

The limit: it is one page, on your machine, on your network. Ten templates mean ten manual runs.

2. Search engine panels

Google Search Console and Yandex Webmaster are free and irreplaceable: only they show which pages are actually indexed, which queries bring impressions, and what the crawler stumbled over. The limits: you must prove you own the site, data arrives with a delay of days, and it describes the past — a broken robots.txt shows up there after the traffic has already dropped.

3. Speed: PageSpeed Insights and CrUX

PageSpeed Insights combines a Lighthouse lab run with field data from the Chrome UX Report — what real visitors experienced over 28 days. The thresholds are LCP ≤ 2.5 s, CLS ≤ 0.1 and INP ≤ 200 ms (background in our guide to Core Web Vitals). The limits: field data exists only for sites with enough traffic, and the tool analyses one URL at a time.

4. The command line

Three commands cover a large share of the technical layer:

curl -sI https://example.com/
openssl s_client -connect example.com:443 -servername example.com </dev/null 2>/dev/null | openssl x509 -noout -enddate
dig +short TXT _dmarc.example.com

Headers and redirects, the certificate's expiry date and mail authentication — in seconds. The limit: you need to know what to ask and how to read the answer.

5. Online scanners

A scanner bundles the above: it walks several pages, reads service files, checks headers, DNS, certificate and links, and puts everything in one report with severities. That is the fastest way to get the whole picture — and SiteScan's free scan needs no sign-up. What it covers is listed on the product page; browsing recent public reports shows what a real result looks like before you run your own. If a row in the report is unclear, the help centre explains every check, for example how the performance score is calculated.

Where free ends

Free analysis is a snapshot, and snapshots have predictable gaps:

• Coverage. A free scan reads a limited number of pages. On a shop with 5,000 products, problems in a rare template may simply not be in the sample.
• Time. A one-off check says nothing about tomorrow. A certificate that expires in 12 days looks fine today.
• Depth. Testing forms by actually filling them in, or a full check of every link, takes more work than a quick pass.
• Access. Anything behind a login, and sites behind aggressive bot protection, are out of reach for any external scanner.

For SEO specifically, we cover the same boundary in free SEO audit.

When it makes sense to pay

Pay when the cost of a missed problem is higher than the cost of the check: a large catalogue, an agency reporting to clients, a site where forms are the business, or a team that needs to know about regressions before customers do. SiteScan sells credits rather than subscriptions; the audit types on the pricing page differ by the number of pages and add AI form testing, a full link check and PDF export. Regular checks with notifications are covered in automated website checks.

A free plan that works

1. Run a free scan and fix everything marked critical or high.
2. Connect Search Console and Yandex Webmaster — they cost nothing and show what no scanner can.
3. Check speed in PageSpeed Insights for your three most important templates.
4. Repeat the scan after each release and compare: the report shows what was fixed and what is new.