Quick answer: Target one main keyword per page, write a 50–60 character title and a 120–160 character meta description, use a short hyphenated URL slug, structure content with H1–H3 headings, add internal links and compress images with alt text.
On-page SEO is everything you control on the page itself to help search engines understand it and to make people want to click. Follow this checklist on every page you publish — and use our free SEO tools to speed things up.
1. Pick one main keyword per page
Choose a primary keyword that matches what people actually search for (for example merge pdf online free), plus a few closely related phrases. Each page should target its own keyword so your pages don’t compete with each other.
2. Write a compelling title tag
- Keep it to 50–60 characters.
- Put the main keyword near the start.
- Make it clickable — include a benefit like “Free”, “Fast” or the year.
3. Write a meta description that earns the click
Meta descriptions aren’t a direct ranking factor, but they strongly influence click-through rate. Aim for 120–160 characters, include the keyword and a clear call to action. Generate both tags — plus Open Graph tags for social sharing — with the Meta Tag Generator, which shows a live Google preview.
4. Use a short, clean URL slug
Good: /tools/merge-pdf/. Bad: /page?id=1234&ref=xyz. Use lowercase words separated by hyphens and drop filler words. The URL Slug Generator does this automatically.
5. Use keywords naturally
Include your keyword in the first paragraph, at least one heading and the image alt text — then write naturally. Paste your draft into the Keyword Density Checker to spot over-used words. If one phrase stands out far above the rest, rewrite some sentences.
6. Structure content with headings
Use one H1 (the page title), then H2s for main sections and H3s for sub-points. Clear structure helps readers skim and helps search engines and AI assistants understand your content.
7. Add internal links
Link related pages together with descriptive anchor text — just like this guide links to each tool. Internal links help Google discover your pages and keep visitors exploring.
8. Optimise images
Compress and resize images so pages load fast — see our guide on compressing images without losing quality — and always add descriptive alt text.
9. Get the length right
Cover the topic fully, then stop. Our guide on ideal content length explains how long different pages should be, and the Word Counter keeps you on target.
Quick on-page SEO checklist
- ☐ One focus keyword
- ☐ Title tag 50–60 characters
- ☐ Meta description 120–160 characters
- ☐ Short, hyphenated URL slug
- ☐ Keyword in first paragraph and an H2
- ☐ Logical H1 → H2 → H3 structure
- ☐ 3+ relevant internal links
- ☐ Compressed images with alt text
Keep reading: related guides
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