About Seokla

Seokla is a set of free tools for checking the technical side of a web page: how fast the server answers, how heavy the code is, how the page is built. You paste an address, and you get a report in plain language.

Why this project exists

Technical SEO reports are often written for people who already know the subject. Seokla has three goals:

• Be clear to a beginner. Every report starts with a short verdict and explains each finding in everyday words. The raw figures follow for those who want them.
• Be honest about what a number means. Where a limit comes from Google’s documentation, we say so. Where a mark is our own guide, we label it as Seokla’s own. Each tool also says what it cannot tell you.
• Stay free and simple. There is no sign-up and nothing to install.

Who makes it

Seokla is built and maintained by Sandr Chenk, a senior SEO and technical SEO specialist. The tools, the scoring and the texts on this site are written by the same person, so there is one place to send corrections.

The tools

• TTFB Test. Measure Time to First Byte, then see what it looks like on a phone, on a slower network and from other parts of the world.
• Round Trip Time (RTT) Test. See how long it takes a signal to reach your server and come back.
• Network Dependency Tree. Map the files a browser must fetch before it can show your page, and find the ones hidden behind other files.
• Lighthouse Throttling Simulator. Run Lighthouse once and see how your page’s FCP and LCP would change across a range of connection speeds.
• Core Web Vitals History. Follow your Core Web Vitals week by week, as real Chrome users experienced them, for a page or a whole site.
• Text to HTML Ratio Checker. Find out what share of your page’s code is text people can read, and what the rest is made of.
• HTML Size Analyzer. Measure the size of your page’s HTML, see what it is made of and find out what could be trimmed.
• DOM Size Checker. Count the elements your page is built from, find the deepest and the widest parts of it, and see what holds up the first paint.
• Schema Validator. Find the structured data in your page’s code, check that it is valid, and see whether each item has the properties Google asks for.
• NoScript Test. Check what your page shows when JavaScript doesn’t run: the text, the links, the images and the fallbacks in its noscript tags.
• HTTP Header Checker. Read the HTTP headers your server sends with a page, follow its redirects, and check the headers that matter for search, caching and security.
• Traceroute Test. Trace the route from our server to yours, router by router, and see where the time goes.

The full list is on the Tools page. New tools are added over time.

How a check works

• Our server requests the page you entered, the way a search engine’s crawler would. It identifies itself as SeoklaBot, so you can find these visits in your server logs.
• Only pages that are open to everyone can be checked. We don’t log in anywhere and don’t get past passwords or paywalls.
• Most tools read the page’s code as the server sends it, without running scripts. Content that JavaScript adds later is not counted, and the report says so where it matters.
• Some tools offer a test from your own browser. In that case the timing is taken on your device and your connection.
• Results are measurements taken at one moment. Run the check again later and the figures can differ a little.

How scores are worked out

Each tool gives a score from 0 to 100 and explains on its own page how the score is calculated. The scores are Seokla’s own scale. They are not Google’s scores, and a high score here is not a promise of better rankings. Use them to compare a page with itself before and after a change.

Limits

Each tool can be used 2 times a day per visitor. The count starts again at midnight, site time. The limit keeps the service free and stops it being used to load other people’s sites.

Your data

• Seokla does not keep a list of the addresses you check and does not save the reports. A report exists only in your browser until you leave the page.
• To count the daily limit we set one cookie, seokla_id, and keep a counter tied to it and to your IP address. Both are stored as a one-way hash and expire the next day.
• Your browser remembers one thing locally: how long the last check took, to pace the progress bar.
• Some tools pass the address you entered to an outside service to do the measuring: the TTFB, RTT and Traceroute tests use Globalping for tests from other cities and for routes, and the full test in the Network Dependency Tree tool uses Google’s PageSpeed Insights.
• A message sent through the contact form goes to us by e-mail and is not saved on this site. Your name and e-mail address are used only to reply to you.
• Like most websites, our server may keep standard access logs for a short time to keep the service running.

Corrections and contact

If a report looks wrong, or a tool you need is missing, write to the author: the ways to do it are on the Contact page. Mistakes that are confirmed get fixed in the tool and in its description.