How to Check a Website Page for Common On-Page SEO Errors

To check a page for on-page SEO errors, look at the elements search engines read first: whether the page can be indexed, its title tag, meta description, headings, canonical URL, image alt text, internal links and structured data. An error is anything that stops the page being indexed, confuses search engines about what it is about, or makes it look unappealing in results.

You can inspect these by viewing the page source, but a website SEO checker reads them all in seconds and flags the problems in one report. The skill lies in knowing which flags matter and which are cosmetic.

Sort errors by severity before you fix anything

Automated reports tend to list every finding with equal urgency. In practice, on-page issues fall into three tiers.

Tier 1: errors that stop a page appearing at all

• A noindex robots meta tag or X-Robots-Tag header left over from development.
• A canonical tag pointing to a different page, telling search engines to index that URL instead.
• The page blocked in robots.txt, so crawlers cannot read it. (Note that robots.txt controls crawling, not indexing; a blocked URL can still appear in results without a description.)
• An error status code, such as 404 or 500, returned for a page that looks fine in a browser.

Tier 2: errors that weaken relevance and click-through

• A missing, duplicated or vague title tag.
• No H1, or several competing H1s that describe different things.
• A missing meta description, which leaves the search snippet entirely to chance.
• Thin content that does not answer the query the page targets.

Tier 3: refinements

• Images without descriptive alt text.
• Few internal links pointing to or from the page.
• Missing or invalid structured data.
• Long or parameter-heavy URLs.

Fix tier 1 immediately, tier 2 next, and tier 3 as part of routine improvement.

Worked example: auditing a sample service page

Here is a sample on-page SEO check for the “Roof Repair” page of a fictional roofing contractor in Ohio. The page had been live for months but received almost no search traffic.

Line 1 explains the missing traffic on its own. The page tells search engines not to index it. This often happens when a site is built on a staging server with indexing switched off and the setting is copied to the live site. Remove the tag and request reindexing in Google Search Console.

Line 2 compounds the problem. Even without the noindex tag, the canonical tag tells Google the “real” version of this page is the general services page. Set the canonical to the page’s own URL.

Line 3. Seven pages share the title “Services | Smith Roofing”, so none of them tells searchers or Google what makes it different. A specific title such as “Roof Repair in Columbus, OH | Smith Roofing” names the service and the area people search for.

Line 4. Without a meta description, Google builds the snippet from page text, which on this page means a navigation fragment. Write one or two sentences that describe the service and give a reason to call.

Line 5. The theme wraps the logo in an H1 on every page, creating two H1s here. Multiple H1s are not forbidden, but a single clear H1 that matches the page’s topic is cleaner. Change the logo to a non-heading element.

Line 6. At 180 words the page cannot answer what a homeowner wants to know: signs of roof damage, typical repair types, how quotes work, insurance claims, service areas. There is no magic word count, but the page needs enough substance to be the best answer for “roof repair near me” in its area.

Line 7. Five project photos lack alt text. Describe what each shows (“Replacing storm-damaged shingles on a ranch-style home”) for accessibility first and image search second.

Line 8. Only one internal link points here. Linking from the home page, relevant blog posts and the contact page helps both visitors and search engines find it.

After the fixes, the key parts of the page’s head look like this:

Audit your own page: paste any URL into the free on-page SEO checker to see its indexability, title, description, headings, images and links in one report, then fix the findings tier by tier.

Where automated checks fall short

An SEO checker reads code, not meaning. It can confirm a title exists and estimate whether it will be cut off, but it cannot tell you whether the title matches what your customers actually type. It can count words, but not judge whether those words answer the question better than competing pages. Use the report to remove technical obstacles, then read the page as a customer would.

Checks to run alongside an on-page audit

Some problems sit outside the page’s HTML altogether. Slow loading affects visitors and Core Web Vitals, which a website speed test measures. Once you have rewritten titles and descriptions, a SERP preview tool shows roughly how they will look in Google before you publish.

Frequently asked questions

What are the most common on-page SEO mistakes?

The ones seen most often are duplicate or generic title tags, missing meta descriptions, stray noindex tags from development, incorrect canonical tags, thin content and images without alt text. The noindex and canonical errors are the most damaging because they can remove a page from search results entirely.

How do I check if a page is indexed by Google?

Use the URL Inspection tool in Google Search Console for a definitive answer. A quick informal check is searching for site: followed by the exact URL. If the page is missing, check for a noindex tag, a canonical pointing elsewhere, a robots.txt block or an error status code.

Does every page need a meta description?

It is good practice for important pages. Google does not use the meta description as a ranking factor and may rewrite it, but a clear description often becomes the snippet and can improve how many searchers click. Pages without one leave Google to pick text from the page, which can be unhelpful.

Is having more than one H1 an SEO error?

Not strictly. Search engines can handle several H1s. It becomes a problem when the extra H1s are repeated template text, such as a logo, that dilutes what the page is about. One descriptive H1 that matches the page’s main topic is the clearest approach.

Most on-page SEO errors are quick to fix once you know they exist, and a single stray tag can matter more than hours of content work. Run your key pages through the TechBullion SEO audit tool, clear the tier 1 issues first and recheck after every redesign or template change.