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On-Page SEO Checklist: 23 Items Most People Miss (2026)

May 16, 2026
Southern Whale
On-Page SEO 23-item checklist

On-Page SEO is something everyone who writes web content needs to understand — it’s the difference between a page that ranks and one nobody sees. This checklist covers 90% of what matters.

Title Tag (3 items)

1. Title has the primary keyword near the front

  • Bad: “Welcome to Southern Whale, Your Web Development Partner”
  • Good: “Web Development Phuket — Southern Whale”

2. Title is 50-60 characters

Too long and Google truncates it. Too short and you waste available real estate.

3. Every page Title is unique

No two pages share a Title (including Home/About, which some sites accidentally make identical with company name).

Meta Description (2 items)

4. Every important page has a Meta Description

Without one, Google pulls a random snippet from the page — never compelling.

5. Meta Description sells the click

Not just “describes” — must persuade. Include: Value Proposition + CTA + Specific number.

Example:

  • Bad: “Web development service in Phuket by Southern Whale.”
  • Good: “Web development in Phuket built on Astro/Next.js → PageSpeed 90+ on Day 1 / SEO-ready / 4-16 week delivery — request a free quote.”

H1 (3 items)

6. Exactly one H1 per page

Not zero (no main heading) and not multiple (creates confusion).

7. H1 contains the primary keyword

Not “Welcome” or “Hello.”

Title is for the SERP, H1 is for the reader. They can differ.

Heading Structure (2 items)

9. Correct heading hierarchy

H1 → H2 → H3 → H4. Don’t skip (H1 → H3 is wrong).

10. Headings include secondary keywords

H2/H3 use related terms (pulled from Ahrefs).

Content (5 items)

11. Word count matches intent

  • Informational (“what is XXX”): 1,500-2,500 words
  • Commercial (“XXX pricing”): 800-1,500 words
  • Transactional (“hire XXX”): 600-1,000 words
  • Local Landing (“XXX Phuket”): 1,000-2,000 words

12. Primary keyword 3-7 times in content

No stuffing — natural and readable.

Google understands topic via related terms — a piece on “SEO” should include “Google,” “Backlink,” “Keyword Research.”

14. First paragraph (above the fold) includes the primary keyword

Google weighs the first 100 words more heavily.

15. Content matches search intent

Someone searching “what is Local SEO” wants definitions + how-to — not “our Local SEO service.”

Link to related pages on your own site.

17. Anchor text matches the target page’s focus

Not “click here.” Good: “Read the complete Local SEO guide.”

Images (3 items)

18. Alt text actually describes the image

  • Bad: alt=“image1.jpg”
  • Good: alt=“Pool Villa Karon hotel website that increased direct bookings 300%“

19. Descriptive filenames

  • Bad: IMG_4837.jpg
  • Good: phuket-pool-villa-website-redesign.jpg

20. Optimized image size

JPG/WebP for photos, SVG for icons/logos. Under 200KB per image.

URL Structure (1 item)

21. URLs are short with the primary keyword

  • Good: /blog/local-seo-guide-2026/
  • Bad: /blog/post.php?id=4837&category=seo&date=2026-01-15

Schema (1 item)

22. Use Schema appropriate to the page type

  • Blog post → Article + BreadcrumbList
  • Service page → Service + LocalBusiness
  • FAQ → FAQPage
  • Product → Product + Review + AggregateRating

Mobile (1 item)

23. Mobile readability

  • Font 16px+ on mobile
  • Short paragraphs (2-3 sentences)
  • Use bullets, numbers, headings to break up blocks

How to Work Through the Checklist Without Burning Out

Strategy 1: One page per week Don’t start with 100 pages at once. Pick your most important page (money page), make it complete on all 23 items → measure results for 30 days → expand.

Strategy 2: Use tools

  • Surfer SEO — analyzes top 10 ranking content and tells you what to add.
  • Frase.io — writes content that’s already optimized.
  • Yoast / Rank Math (WordPress) — runs basic checks automatically.
  • Ahrefs Content Gap — finds topics competitors cover that you don’t.

Strategy 3: Monthly audit Use Google Search Console to find pages with high impressions but ranking 10-30 → apply this checklist → see results within 30 days.

Request a Content Audit

If you have 50+ articles and need help prioritizing which to fix first, request a deep SEO Audit — content audit is included in every audit package.

If you’d rather have us write new, pre-optimized content, see our SEO service — includes 4-10 articles/month.