The Grand Library of SEO Issues: A Complete Catalog

Welcome to the most comprehensive corner of our Learn section. Here, we’ve gathered every potential SEO issue that Creeper can help you identify and resolve. Think of this as your master index for a truly healthy website. From the smallest on-page error to the most critical server problem, we’ve got you covered. Understanding the full spectrum of all issues is the first step to achieving SEO excellence.

Whether you’re a seasoned SEO professional or just starting out, this category is your go-to resource for diagnosing and fixing any problem that might be holding your website back. For a great starting point on your SEO journey, check out the official SEO Starter Guide from Google.

Your Guide to a Flawless Website

Below you’ll find a list of all the individual Learn pages, categorized to help you prioritize your efforts effectively.

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When One URL Isn’t Enough: The Danger of Multiple Canonical Tags

Discover why having multiple canonical tags on a single page is a critical SEO issue. Learn how to identify and resolve conflicting canonical signals.

From Tangled Mess to Clear Message: Conquering Difficult Readability

Learn why difficult readability is a major roadblock for both users and SEO. Discover how to improve your content’s readability score and create a better user experience.

The Art of the Digital Detour: A Guide to 3xx Redirects

Learn what 3xx redirects are, how they can impact your SEO, and how to use them effectively to improve your website’s user experience and search engine rankings.

Breaking Down the Wall of Text: A Guide to Very Difficult Readability

A guide to identifying and fixing very difficult readability issues on your website. Learn how to transform your most challenging content into an accessible and engaging resource.

When the Web Goes Silent: A Guide to External No Response Errors

Learn what external no response errors are, how they can impact your SEO, and how to find and fix them for a more reliable and user-friendly website.

The Digital Dead End: How 4xx Client Errors Can Stall Your SEO

Learn what 4xx client errors are, how they can harm your SEO, and how to find and fix them to improve your website’s health and user experience.

When Your Server Takes a Sick Day: A Guide to 5xx Server Errors

Learn what 5xx server errors are, how they can damage your SEO, and how to troubleshoot and fix them for a more stable and reliable website.

The SEO Seal of Approval: Understanding ‘Canonicalised’

Explore the meaning of the ‘Canonicalised’ status in an SEO audit. Learn why it’s a good sign and how it indicates that your duplicate content is being handled correctly.

The Missing Pages: A Guide to URLs Not in a Sitemap

Learn about the importance of including all of your important URLs in your sitemap and how to fix a sitemap that is missing URLs.

From Barren to Bountiful: Transforming Low-Content Pages for SEO

Thin or low-content pages can hurt your SEO rankings. Learn how to identify and fix these pages by adding value and improving user experience.

Closing the Backdoor: Securing Your Cross-Origin Links

Learn how to secure your cross-origin links using rel=’noopener’ and ‘noreferrer’ to prevent security vulnerabilities like tabnapping.

The HSTS Header: A Shield for Your Website’s Security

A missing HSTS header can leave your site vulnerable. Learn what the HSTS header is, why it’s important for security, and how to implement it correctly.

The X-Content-Type-Options Header: A Shield for Your Website

A missing X-Content-Type-Options header can leave your site vulnerable to MIME-sniffing attacks. Learn how to implement this crucial security header.

Referrer-Policy: Balancing Security and SEO Analytics

A missing Referrer-Policy header can impact your analytics data. Learn what the Referrer-Policy header is and how to implement it for better security and data accuracy.

The Art of Concise Alt Text: A Guide for SEO

Long alt text can be bad for accessibility and SEO. Learn why keeping your alt text under 100-125 characters is a best practice for image optimization.

The Goldilocks Zone: Finding the Perfect Meta Description Length

Does meta description length matter for SEO? Learn why keeping your descriptions between 150-160 characters is a best practice for avoiding truncation and improving click-through rates.

The More the Merrier: A Guide to Using Multiple H2 Tags

Learn why it’s not only okay to have multiple H2 tags on a page, but it’s actually a good practice for SEO. A guide to creating a clear and logical heading structure.

The Unwritten Chapter: A Guide to Fixing Missing H2 Tags

Learn why missing H2 tags can be a problem for SEO and how to fix them. A guide to creating a clear and logical heading structure for your content.

Seeing Double: A Guide to Fixing Duplicate H2 Tags

Learn why duplicate H2 tags can be a problem for SEO and how to fix them. A guide to creating unique and descriptive H2 tags for every section of your page.

Cutting it Short: A Guide to Taming Your Long H1 Tags

Learn why H1 tags over 70 characters can be a problem for SEO and user experience, and how to write concise, effective H1 tags that are ‘just right’.

The Great Separator: Why Hyphens Beat Underscores in URLs

Should you use hyphens or underscores in your URLs? Discover why Google prefers hyphens for SEO and how to fix URLs that use underscores.

Taming the Beast: A Guide to URL Parameters and SEO

URL parameters can create duplicate content and waste crawl budget. Learn how to manage parameters with canonical tags and robots.txt to protect your SEO.

The Silent Link: A Guide to Fixing Internal Links with No Anchor Text

Internal links with no anchor text are a missed opportunity for SEO. Learn why descriptive anchor text is crucial for context and how to find and fix these silent links.

The Sweet Spot for H2 Tags: A Guide to Heading Length

Are your H2 tags too long? Learn why keeping H2 headings under 70 characters is a best practice for readability, user experience, and SEO.

The Global Handshake: Why Your Hreflang Needs an ‘x-default’

Learn why the x-default hreflang attribute is crucial for international SEO, how it improves user experience, and the correct way to implement it.

Page Title vs. H1: A Tale of Two Headlines

Should your page title and H1 tag be the same? Learn the difference between the two, their roles in SEO, and best practices for optimizing both.

The Echo Chamber: How Duplicate Meta Descriptions Hurt Your SEO

Duplicate meta descriptions can lower your click-through rate and confuse search engines. Learn how to write unique, compelling descriptions for every page, even at scale.

Breaking the Echo: A Guide to Fixing Duplicate H1 Tags

Learn why duplicate H1 tags can be a problem for SEO and how to fix them. A guide to creating unique and descriptive H1 tags for every page.

The Dead End: Why Non-200 URLs Invalidate Your Hreflang Tags

Using non-200 URLs (redirects, 404s, etc.) in your hreflang tags breaks the required chain of reciprocal links. Learn why every hreflang URL must be a live, 200 OK page.

The Missing Link: Why Unlinked Hreflang URLs Are an SEO Problem

Unlinked hreflang URLs create orphan pages that are difficult to crawl and rank. Learn why internal linking is a crucial, separate step for your international SEO strategy.

Don’t Sell Yourself Short: The SEO Pitfalls of Short Page Titles

Are your page titles too short? Learn why titles under 30 characters can harm your SEO by failing to provide context and keywords for search engines.

The 100KB Rule: Optimizing Image Size for Page Speed and SEO

Large images slow down your site and hurt Core Web Vitals. Learn why keeping images under 100KB is a critical best practice for page speed and user experience.

Seeing Double: Why Duplicate Page Titles Are an SEO Red Flag

Duplicate page titles confuse search engines and hurt your click-through rate. Learn why unique titles are critical for SEO and how to fix them.

Pages With High External Outlinks: Don’t Let Your SEO Juice Leak

Imagine your website is a bucket full of water (which represents authority or “link juice”). Every link you place on a page is a tiny hole in that bucket. A few holes are necessary to water the garden—linking to authoritative sources is good! But if you have pages with high external outlinks, your bucket might […]

Page Titles Over 55 Characters: Stop the Truncation…

Have you ever searched for something and seen a result that ends with “…”? That is the sound of a sentence falling off a cliff. If your website has page titles over 55 characters, there is a good chance your most important keywords are invisible to users on Google. The page title length is one […]

For another excellent resource, check out this guide to SEO for beginners from Moz.

A comprehensive SEO health dashboard showing various metrics and scores.

FAQs

What are the most common SEO issues?

Some of the most common SEO issues include slow page speed, duplicate content, broken links (404 errors), missing or poorly optimized meta tags, and a lack of mobile-friendliness.

How often should I check for SEO issues?

It’s a good practice to conduct a comprehensive SEO audit at least once a quarter, and to monitor your site for critical issues on an ongoing basis using a tool like Creeper or Google Search Console.

What is the difference between an 'error' and a 'warning' in an SEO audit?

An ‘error’ is a critical issue that is actively harming your SEO and should be fixed immediately (e.g., a 500 server error or a noindex tag on an important page). A ‘warning’ is a less critical issue that may not be causing immediate harm but represents a missed opportunity for optimization (e.g., a meta description that is too long).

Ready to tackle all your SEO issues head-on? Start your comprehensive audit with Creeper today.

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