https://posthog.com

H1 heading is missing or duplicated

Every page should have exactly one main heading (H1) that tells Google what the page is about. Missing or multiple H1s confuse search engines and lower your rankings.

Open Graph image URL is broken

You have an og:image tag, but the image URL is broken — it returns an error. Social media sites will show a placeholder or nothing when your link is shared.

OG image missing width and height

Twitter/X, LinkedIn, Telegram, and Discord need the image dimensions declared in your HTML to display the preview correctly. Without them, the preview may be skipped entirely or shown at the wrong size — reducing click-through rate when your link is shared.

Images are missing alt text

Some images have no alt text. Screen readers and search engines lose context, and image search previews are weaker.

Images are missing dimensions

Images without dimensions can cause layout shifts while the page loads. That hurts Core Web Vitals and makes the page feel unstable.

Images with empty or missing alt text

Some images have no meaningful alt text. Screen readers read these as "image" with no context, hurting accessibility and image search visibility.

No structured data (JSON-LD) found

No Schema.org JSON-LD blocks were found on this page. Structured data helps Google understand your content and display rich results. It also improves AI search visibility.

No analytics tracking detected

You can't improve what you don't measure. Without analytics you have no visibility into traffic, user behavior, or conversion goals.

X-Frame-Options header missing

Your site can be embedded in an invisible iframe on another website. Attackers use this technique (called "clickjacking") to trick your users into clicking things without realising it.

X-Content-Type-Options header missing

Browsers can "sniff" your files and treat them as a different file type than intended. This can allow attackers to upload files that get executed as scripts. This header prevents that.

Referrer-Policy header missing

When visitors click a link to leave your site, their browser sends your full URL (including any private query parameters) to the destination site. A referrer policy controls what gets shared.

Content Security Policy missing

There's no policy controlling what scripts and resources your page can load. Without this, an attacker who injects any code into your page can do anything — steal cookies, redirect users, exfiltrate data.

Mixed content — HTTP resources on HTTPS page

Your HTTPS page loads some resources (images, scripts, or styles) over insecure HTTP. Browsers block or warn about this, causing parts of your page to break or display incorrectly for visitors.

Missing Permissions-Policy header

Without a Permissions-Policy header, any script on your page can access the camera, microphone, geolocation, and other sensitive browser features. This is a defence-in-depth security header that limits exposure if you get XSS.

No CAA DNS record

Without a CAA record, any certificate authority in the world can issue an SSL certificate for your domain. A CAA record restricts which CAs are allowed.

No cookie consent mechanism detected

Your site loads tracking scripts (Google Analytics, Meta Pixel, etc.) but no cookie consent banner was found. GDPR and similar laws require informed consent before tracking EU visitors — fines can reach €20M.

No privacy policy link found

A privacy policy link is legally required in most jurisdictions if you collect any user data. It also builds trust with visitors who want to understand how their data is handled.

No structured data (Schema.org)

AI assistants and search engines use structured data to understand what your product is. Without it, they have less reliable context.

Heading hierarchy is broken

The page outline skips heading levels. That makes machine parsing and assistive reading less reliable.

No llms.txt file

An llms.txt file can help AI systems understand which product pages and context to prefer.

No content date signal found

Perplexity and Google AI Overview weight fresh content significantly higher. Without a date signal, your page may be treated as potentially outdated — reducing how often AI systems cite it in answers.

First paragraph too short for AI citation

AI systems like ChatGPT, Claude, and Perplexity extract the beginning of your page as citation passages. A short or absent opening paragraph means they have little useful content to cite, reducing how often your page appears in AI answers.

Images missing alt text (accessibility)

Some images have no alt attribute at all. Screen readers will say "image" with no context, or skip the image entirely. This is an unambiguous accessibility failure.

Buttons without accessible label

Some buttons (icon buttons, hamburger menus, close buttons) have no accessible name. Screen readers will say "button" with no context — users cannot tell what clicking the button does.

Missing lang attribute on html element

Your page has no language declaration. Screen readers need this to choose the right pronunciation engine. Without it, content may be read in the wrong language, making it incomprehensible for visually impaired users.

No skip navigation link

Keyboard and screen reader users have to tab through every navigation item on every page to reach the main content. A "skip to content" link at the top of the page lets them jump directly to the main area.