Free On-Page SEO Checker: 17 Checks, a Weighted Score, and a Live Demo
Most SEO problems aren't exotic. They're missing title tags. Meta descriptions that got truncated at 220 characters. A page with three H1s because a CMS template got copy-pasted. A canonical pointing to HTTP instead of HTTPS. These issues compound quietly — individually small, collectively significant.
Our free On-Page SEO Checker runs 17 checks against any URL and returns a 0–100 score. No account required. No data stored. Results in seconds.
Below is this site — redirectiq.com — audited in real time. The score is generated fresh on each page load by calling the same API the tool uses.
Let's walk through what each check means and why the weights are set the way they are.
How the score is calculated
Each of the 17 checks has a weight between 5 and 10, totaling 105 possible points. A passing check earns its full weight. A warning earns half. A fail earns nothing. The final score is:
score = round((earned_weight / total_weight) × 100)A missing title tag (weight 10) costs more than a missing OG image (weight 5). The weights reflect what Google has signaled matters most for indexing and ranking — not all checks are created equal.
Title & Meta (30 points)
Title tag present (weight: 10)
The title tag is the single most important on-page SEO element. It appears as the clickable link in search results and is the primary signal for what the page is about. Google may rewrite titles, but it starts with yours. A missing title is a hard fail — Google synthesizes one from your content, usually poorly.
Title length: 50–60 characters (weight: 5)
Google displays roughly 600 pixels of title text, which corresponds to 50–60 characters at typical screen widths. Too short and you leave keyword space on the table. Too long and Google truncates with an ellipsis, potentially cutting the most relevant part. The check has a warning zone (40–70 chars) to avoid flagging titles that are close but not clearly wrong.
Meta description present (weight: 10)
Google rewrites meta descriptions roughly 70% of the time with content it finds more query-relevant. But when it uses yours, the description drives click-through directly. A missing description means Google always improvises from body copy — often choosing a sentence that makes sense out of context but doesn't function as a call to action.
Meta description length: 120–160 characters (weight: 5)
The display limit is approximately 160 characters. Shorter is fine — it just reduces control over the snippet. Longer means Google truncates at an arbitrary point. The warning zone (100–180 chars) separates borderline cases from clearly wrong ones.
Headings (20 points)
H1 tag present (weight: 10)
The H1 is the on-page title — distinct from the <title> tag that appears in the browser tab and search results. Google uses the H1 to confirm the page's primary topic. A page without one isn't broken, but it's missing the clearest topical signal available.
Single H1 (weight: 5)
Multiple H1s were never technically invalid HTML, but they signal unclear hierarchy. Google's guidance has consistently been that one per page is cleaner. The check flags multiple H1s as a warning rather than a fail, because some page templates produce two H1s unintentionally without meaningful SEO impact.
H2 subheadings present (weight: 5)
H2s help crawlers understand document structure and help readers scan. A wall of text with no subheadings is harder to crawl and harder to read. This is a warning rather than a fail because some pages — particularly landing pages — are intentionally short and structure-free.
Technical SEO (25 points)
HTTPS (weight: 5)
Google confirmed HTTPS as a ranking signal in 2014. HTTP pages signal to users and crawlers that the page isn't secured. This is a hard fail because there is no valid reason to serve a public page over HTTP.
Canonical tag present (weight: 8)
The canonical tag tells search engines which URL is the authoritative version of a page. Without it, Google infers — and if you have URL parameters, trailing slashes, or HTTP/HTTPS variants, it may index the wrong one. The canonical is the most direct mechanism for controlling which URL accumulates ranking signals. This gets weight 8 because the consequences of a wrong or missing canonical are hard to detect and take months to reverse.
Viewport meta tag (weight: 7)
The viewport tag controls how a page renders on mobile. Without it, mobile browsers render at desktop width and scale down. Google uses mobile-first indexing — the mobile version of your page is what gets crawled and indexed. A missing viewport tag directly degrades mobile usability scores.
Server response time (weight: 5)
This measures the time from the fetch request to receiving the first byte of HTML — a proxy for TTFB, one of Google's Core Web Vitals signals. Under 2 seconds is a pass. Between 2–4 seconds is a warning. Over 4 seconds is a fail. Fast server response is table stakes; slow response compounds every other performance issue on the page.
Social Sharing (15 points)
OG title, description, and image (weight: 5 each)
Open Graph tags control how your pages appear when shared on social platforms — LinkedIn, Twitter/X, Slack, iMessage, and any link unfurler. Without them, platforms fall back to the page title and random images, or show nothing.
These three checks are each worth 5 points and treated as warnings rather than fails, because missing OG tags don't affect search ranking directly — they affect engagement from social. The og:image is the most impactful: links shared with a preview image consistently get higher click-through than links without one.
Content signals (15 points)
Image alt text (weight: 8)
Alt text serves two purposes: it's what screen readers use for accessibility, and it's how Google understands what an image contains. The check distinguishes between no images (pass), all images tagged (pass), 1–2 missing alt text (warning), and 3+ missing (fail). Weight 8 reflects that both the accessibility and SEO implications are significant — and both are easy to fix.
Structured data / Schema markup (weight: 7)
Structured data is the mechanism Google uses to generate rich results — star ratings, FAQs, breadcrumbs, events, and more. It doesn't directly affect standard search ranking, but rich results get higher click-through rates and occupy more SERP real estate. The check detects application/ld+json script tags and itemscope attributes. It's a warning rather than a fail because structured data is an enhancement, not a baseline requirement.
Using the SEO Checker with our other tools
The SEO Checker is most useful as part of a workflow, not in isolation. Here's how it composes with our other free tools:
Before setting up redirects — use the Redirect Checker to confirm the destination URL resolves correctly and returns the right status code (301 vs 302 matters for link equity). Then run the SEO Checker on that same destination to verify it's optimized before you send traffic and link equity its way. There's no point in a clean 301 landing on a page missing a canonical.
After a domain migration — use the Redirect Chain Analyzer to verify your redirect chains are clean: no double redirects, no loops, no unnecessary hops. Then run the SEO Checker on the destination pages. A missing canonical is a common post-migration problem — the old URL had it set correctly, but the new page template wasn't updated.
For acquired domains — run the SEO Checker on the highest-traffic destination pages. If those pages have structural SEO problems, the link equity arriving from your redirects is landing somewhere that can't capitalize on it. Redirects move link equity; well-optimized destinations convert it into rankings.
The three tools cover the full redirect lifecycle: the chain is clean, the destination resolves correctly, and the destination page is optimized.