Technical SEO Checklist: 15 Items You Need to Get Right

Technical SEO is the foundation that everything else sits on. You can have the best content in the world, but if Google can’t crawl your site, your pages load in 8 seconds, or your URLs are a mess — none of it matters.

This checklist covers the 15 most important technical SEO items, organized into four categories. Work through them in order, fix what’s broken, and you’ll have a technically sound website that search engines love.

Category 1: Crawling & Indexation (Items 1–5)

If Google can’t find and index your pages, nothing else matters. Start here.

1. Robots.txt Configuration

Your robots.txt file tells search engines what they can and can’t crawl. A single misconfiguration can block your entire site from indexing.

What to check:

• File is accessible at yourdomain.com/robots.txt
• Important pages are NOT blocked (check with „Disallow“ directives)
• CSS and JS files are not blocked (Google needs them to render pages)
• XML sitemap URL is referenced
• Staging or development environments ARE blocked

Common mistakes:

• Leftover Disallow: / from development (blocks everything)
• Blocking /wp-admin/admin-ajax.php on WordPress (breaks functionality)
• Not blocking /cart/, /checkout/, /my-account/ (wasted crawl budget)

Tool: Google Search Console → Settings → Crawl Stats

2. XML Sitemap

Your sitemap is a roadmap for search engines. It lists all the pages you want indexed and helps Google discover new or updated content faster.

What to check:

• Sitemap exists and is submitted in Google Search Console
• Contains only indexable pages (no 404s, no redirects, no noindex pages)
• Updated automatically when you publish new content
• Split into multiple sitemaps if you have 10,000+ URLs
• Includes dates that reflect actual content changes

Best practice: Generate your sitemap dynamically. For WordPress, use Yoast SEO or Rank Math. For custom sites, use a server-side script that reflects your actual URL structure.

Tool: Google Search Console → Sitemaps

3. Google Search Console Setup

GSC is your direct communication channel with Google. If you’re not using it, you’re flying blind.

What to check:

• Property is verified (preferably domain-level verification via DNS)
• All relevant properties are added (www vs. non-www, HTTP vs. HTTPS)
• You’re monitoring the Coverage/Indexing report regularly
• Manual actions — check that there are none
• Core Web Vitals report is reviewed monthly

Must-do: Set up email alerts in GSC so you’re notified of critical issues immediately.

Tool: Google Search Console

4. Canonical Tags

Canonical tags tell Google which version of a page is the „original“ when multiple URLs have the same or similar content. Without them, Google has to guess — and it doesn’t always guess right.

What to check:

• Every page has a self-referencing canonical tag
• Paginated pages point to the correct canonical
• HTTP pages canonicalize to HTTPS
• Non-www pages canonicalize to www (or vice versa — pick one)
• URL parameters don’t create duplicate canonical issues

Common issues:

• Multiple canonical tags on the same page (conflicting signals)
• Canonical pointing to a 404 or redirect
• CMS generating incorrect canonicals for filtered/sorted pages

Tool: Screaming Frog → Canonicals tab

5. Duplicate Content

Duplicate content confuses search engines and dilutes your ranking potential. It’s one of the most common technical issues I see during audits.

What to check:

• No identical or near-identical pages at different URLs
• URL parameters are handled correctly (sorting, filtering, tracking)
• Printer-friendly versions are canonicalized or noindexed
• WWW/non-WWW and HTTP/HTTPS redirects are in place
• Trailing slash consistency (choose one and redirect the other)

Quick test: Take a unique sentence from your page, put it in quotes in Google, and search. If multiple pages from your site show up — you have a duplicate content problem.

Tool: Siteliner, Screaming Frog

Category 2: Speed & Performance (Items 6–9)

Page speed is a confirmed ranking factor, and it directly impacts user experience and conversion rates. Every second of load time costs you money.

6. Core Web Vitals

Google’s Core Web Vitals are the three metrics that matter most for page experience:

Metric	What It Measures	Good	Needs Improvement	Poor
LCP (Largest Contentful Paint)	Loading speed	< 2.5s	2.5–4.0s	> 4.0s
INP (Interaction to Next Paint)	Interactivity	< 200ms	200–500ms	> 500ms
CLS (Cumulative Layout Shift)	Visual stability	< 0.1	0.1–0.25	> 0.25

How to improve LCP:

• Optimize your largest above-the-fold image
• Use a CDN
• Preload critical resources
• Reduce server response time (TTFB)

How to improve INP:

• Minimize JavaScript execution time
• Break up long tasks
• Use web workers for heavy computations

How to improve CLS:

• Set explicit dimensions on images and videos
• Avoid inserting content above existing content
• Use font-display: swap for web fonts

Tools: PageSpeed Insights, Chrome DevTools (Lighthouse), Google Search Console → Core Web Vitals

7. Image Optimization

Images are typically the heaviest elements on a page. Optimizing them is one of the quickest wins for page speed.

What to check:

• Images served in modern formats (WebP or AVIF)
• Images are appropriately sized (don’t serve a 3000px image in a 300px container)
• Lazy loading is implemented for below-the-fold images
• Above-the-fold images are NOT lazy loaded (they should load immediately)
• Alt text is descriptive and includes relevant keywords naturally
• Image compression is applied without visible quality loss

Target: Each image should be under 100KB for standard content images, under 200KB for hero images.

Tools: Squoosh, ShortPixel, Imagify

8. Browser Caching

Caching tells browsers to store static files locally so returning visitors don’t have to download them again. This dramatically improves load times for repeat visits.

What to check:

• Static assets (CSS, JS, images, fonts) have cache headers set
• Cache duration is appropriate (CSS/JS: 1 year with versioning, images: 1 year, HTML: no-cache or short)
• GZIP or Brotli compression is enabled on the server
• You’re using file versioning (e.g., style.v2.css) so cache-busting works when you update files

Test: Check your response headers in Chrome DevTools → Network tab. Look for Cache-Control and Content-Encoding headers.

Tools: GTmetrix, WebPageTest

9. JavaScript Rendering

If your site relies heavily on JavaScript to render content, search engines may not see everything. This is a growing issue with modern JS frameworks.

What to check:

• Critical content is available in the initial HTML (not loaded via JS)
• Google can render your pages correctly (use GSC’s URL Inspection → „View Tested Page“)
• Time-to-interactive is under 3 seconds
• Third-party scripts are loaded asynchronously or deferred
• Unused JavaScript is removed or code-split

Red flag: If „View Source“ shows an empty

and all your content is loaded via JavaScript — you have a rendering problem that needs server-side rendering (SSR) or static site generation (SSG).

Tools: Google Search Console (URL Inspection), Chrome DevTools

Category 3: Structure & Content (Items 10–13)

Good site structure helps both users and search engines understand your content and how pages relate to each other.

10. URL Structure

Clean, descriptive URLs are a minor ranking factor but a major usability factor. They should tell both users and search engines what the page is about.

Best practices:

• Use lowercase letters only
• Separate words with hyphens (not underscores)
• Keep URLs short and descriptive (3–5 words after the domain)
• Include your primary keyword naturally
• Avoid URL parameters when possible
• Use a logical hierarchy: /category/subcategory/page-name/

Bad: example.com/p?id=12847&cat=3&ref=home Good: example.com/services/google-ads-audit/

11. Heading Hierarchy

Headings (H1–H6) create a content hierarchy that helps search engines understand your page structure and identify key topics.

Rules:

• Every page has exactly one H1 tag
• H1 contains the primary keyword and accurately describes the page content
• Headings follow a logical order (H1 → H2 → H3, never skip levels)
• Headings are used for structure, not styling (don’t use H2 just because it looks bigger)
• Each major section has its own H2, with H3s for subsections

Common mistakes:

• Multiple H1 tags on a single page
• Using headings for visual styling instead of semantic structure
• Logo wrapped in an H1 on every page
• Skipping heading levels (H1 → H3)

Tool: Browser extension „HeadingsMap“ or Screaming Frog

12. Internal Linking

Internal links distribute page authority throughout your site and help search engines discover and understand your content hierarchy.

What to check:

• Every important page is reachable within 3 clicks from the homepage
• Anchor text is descriptive and relevant (not „click here“)
• Related content is cross-linked (blog posts link to related services and vice versa)
• No orphan pages (pages with zero internal links pointing to them)
• Broken internal links are fixed

Strategy: Identify your most important pages (money pages) and make sure they receive the most internal links. Create content clusters where a pillar page links to and from supporting content.

Tool: Screaming Frog → Internal Linking, Ahrefs → Site Audit

13. Schema Markup (Structured Data)

Schema markup helps search engines understand your content at a deeper level and can earn you rich results (stars, FAQs, how-to steps, etc.) in search results.

Essential schema types:

• Organization: Your business name, logo, contact info
• LocalBusiness: Address, opening hours, phone (for local businesses)
• Article/BlogPosting: For blog content
• Product: Price, availability, reviews (for e-commerce)
• FAQ: Frequently asked questions
• BreadcrumbList: Navigation path
• HowTo: Step-by-step instructions

Implementation:

• Use JSON-LD format (Google’s preferred method)
• Place schema in the or at the end of
• Validate with Google’s Rich Results Test
• Monitor in GSC → Enhancements

Tool: Rich Results Test, Schema Markup Generator

Category 4: Security & UX (Items 14–15)

Security and user experience are table stakes in 2026. Without them, you’re fighting an uphill battle.

14. HTTPS

HTTPS has been a ranking signal since 2014, and in 2026, there’s absolutely no excuse for not having it. Beyond SEO, browsers actively warn users about non-HTTPS sites, which destroys trust and increases bounce rates.

What to check:

• SSL certificate is valid and not expired
• All pages load over HTTPS (no mixed content warnings)
• HTTP-to-HTTPS redirect is in place (301, not 302)
• Internal links use HTTPS URLs
• Canonical tags reference HTTPS URLs
• HSTS header is set for additional security

Tools: SSL Labs, Chrome DevTools (Security tab)

15. Mobile-Friendliness

Google uses mobile-first indexing, which means it primarily uses the mobile version of your site for ranking. If your site doesn’t work well on mobile, it won’t rank well — period.

What to check:

• Responsive design works across all screen sizes
• Text is readable without zooming (minimum 16px font size)
• Tap targets are large enough (minimum 48x48px with adequate spacing)
• No horizontal scrolling
• Forms are easy to fill out on mobile
• Pop-ups don’t cover the main content (Google penalizes intrusive interstitials)
• Page speed is good on mobile connections (test on 3G)

Tools: Chrome DevTools (Device Mode), PageSpeed Insights (Mobile tab)

Summary: Technical SEO Checklist

#	Item	Category	Priority	Key Tool
1	Robots.txt	Crawling	High	GSC
2	XML Sitemap	Crawling	High	GSC
3	GSC Setup	Crawling	High	GSC
4	Canonical Tags	Crawling	High	Screaming Frog
5	Duplicate Content	Crawling	Medium	Siteliner
6	Core Web Vitals	Speed	High	PageSpeed Insights
7	Image Optimization	Speed	High	Squoosh
8	Browser Caching	Speed	Medium	GTmetrix
9	JS Rendering	Speed	Medium	GSC URL Inspection
10	URL Structure	Structure	Medium	Screaming Frog
11	Heading Hierarchy	Structure	Medium	HeadingsMap
12	Internal Linking	Structure	High	Screaming Frog
13	Schema Markup	Structure	Medium	Rich Results Test
14	HTTPS	Security	High	SSL Labs
15	Mobile-Friendliness	UX	High	PageSpeed Insights

Next Steps

1. Run a full crawl with Screaming Frog (free for up to 500 URLs) and note every issue.
2. Check Core Web Vitals in Google Search Console — fix any pages marked „Poor“ first.
3. Fix crawling issues before anything else — if Google can’t see your pages, nothing else matters.
4. Set up monitoring — schedule monthly checks for new issues.

Need a professional technical SEO audit? Contact me for a comprehensive review of your website.

Written by Martin Bradac — PPC & SEO specialist with 9+ years of experience managing €80K+/month in ad spend.