SEO Checker: How to Audit Your Website's SEO (and What to Do With the Results)
Introduction
- An SEO checker is any tool that scans your website and surfaces problems affecting your rankings
- The problem: most SEO checkers give you 200 findings with no priority order — and you don't know where to start
- This guide covers what to actually check, in priority order, and what to do with the results
What an SEO Checker Actually Looks For
SEO checkers vary widely in what they analyze. The best ones cover all four:
| Category | What's checked | Impact |
|---|---|---|
| On-page | Titles, metas, H1s, content quality, keywords | High |
| Technical | Crawlability, indexing, speed, mobile, HTTPS | High (blocks ranking if broken) |
| Content | Thin pages, duplicate content, freshness | Medium–High |
| Authority | Backlink count, domain authority, link quality | Medium (long-term) |
A free checker typically covers on-page and basic technical. A full audit adds content quality and authority.
The Most Important SEO Checks (Priority Order)
1. Indexing: can Google find your pages?
- Check: Google Search Console → Coverage tab
- Look for: "Excluded," "Error," "Valid with warning"
- Fix priority: anything tagged "Error" or "noindex" on pages you want ranked
2. Title tag issues
- Check: every page has a unique, keyword-targeted title under 60 characters
- Common problems: missing title, duplicate titles, too long (gets truncated)
- Impact: highest leverage on-page factor
3. Meta description issues
- Check: every page has a unique meta under 155 characters
- Common problems: missing, too long, auto-generated (usually generic)
- Impact: affects CTR, which affects ranking
4. H1 issues
- Check: one H1 per page, contains the primary keyword
- Common problems: no H1, multiple H1s, H1 doesn't match page topic
- Impact: strong on-page signal
5. Page speed
- Check: Google PageSpeed Insights on your top 5 pages
- Targets: LCP < 2.5s, CLS < 0.1, INP < 200ms
- Impact: Core Web Vitals are a ranking factor; slow pages also hurt bounce rate
6. Mobile
- Check: Google's Mobile-Friendly Test
- Look for: unreadable text, elements too close to tap, horizontal scroll
- Impact: Google indexes mobile-first — mobile problems = desktop ranking problems
7. Thin content
- Check: filter GSC pages by clicks; look for high-impression, zero-click pages
- Look for: pages under 300 words on competitive topics
- Impact: thin pages rarely rank and dilute overall site quality
8. Duplicate content
- Check: search
site:yourdomain.com [your page title]— do multiple pages appear? - Common sources: www vs non-www, HTTP vs HTTPS, trailing slash vs none, print versions
- Fix: canonical tags, 301 redirects
9. Broken internal links
- Check: crawl your site with Screaming Frog free version (up to 500 pages)
- Look for: 404s in internal links — they waste crawl budget and break user experience
- Fix: update or remove broken links
10. Missing alt text
- Check: any image without an
altattribute - Impact: accessibility + image search + page relevance signals
Free SEO Checker Tools
| Tool | Best for | Free limit |
|---|---|---|
| Google Search Console | Real performance data, indexing, Core Web Vitals | Free, no limit |
| Google PageSpeed Insights | Speed and Core Web Vitals | Free, unlimited |
| Screaming Frog | Full site crawl for technical issues | Free up to 500 URLs |
| Ahrefs Webmaster Tools | Backlinks + on-page issues | Free for site owner |
| SerpDo Page Grader | Page-level SEO + GEO score, AI-generated fix list | Free to start |
The most important free tool is Google Search Console. It shows your actual search performance, not just technical issues.
How to Run a DIY SEO Audit in 1 Hour
Step 1 (10 min): GSC Coverage check
- Go to GSC → Coverage → review errors and excluded pages
- Note any "Crawl anomaly," "Server error," or "Submitted URL not found"
Step 2 (15 min): Top pages review
- GSC → Performance → Pages → sort by Impressions
- For each top 10: does the title make you want to click? Is it under 60 chars?
Step 3 (10 min): Speed check
- Run PageSpeed Insights on your homepage and your highest-traffic page
- Note any red or orange metrics
Step 4 (15 min): On-page spot check
- Open your top 5 pages
- Check: one H1? Unique title? Meta description visible? Images have alt text?
Step 5 (10 min): Log findings
- List every issue found
- Tag each: Critical / Important / Nice-to-have
- Start fixing in that order
What to Do After Running an SEO Checker
The biggest mistake: getting overwhelmed by the volume of findings and not acting on any of them.
Triage framework:
- Fix anything blocking indexing first (robots.txt, noindex, server errors)
- Fix on-page issues on your top 20 pages by impressions
- Fix speed issues
- Fix everything else in order of impact
For each page with problems, SerpDo's Page Grader scores it across 8 categories and gives you a ranked fix list — so you know exactly what to change, not just that something is wrong.
How Often to Run an SEO Check
| Check | Frequency |
|---|---|
| GSC Coverage + errors | Weekly (or set up email alerts) |
| Top pages titles/CTR | Monthly |
| Full site crawl | Quarterly |
| Page speed check | After major site changes |
| Content freshness review | Every 6 months |
FAQ
What's the best free SEO checker? For real data: Google Search Console. For page-level analysis: SerpDo's Page Grader gives a 0–100 score per page with a ranked fix plan.
Can an SEO checker hurt my site? No. SEO checkers only read your site — they don't make changes. The risk is acting on bad recommendations from low-quality tools.
My SEO checker says I have 847 issues. Where do I start? Start with indexing errors, then title/meta issues on your top 20 pages, then speed. Ignore cosmetic issues (missing schema on pages that aren't ranking, etc.) until the fundamentals are clean.
Does running an SEO check improve my rankings? Finding problems doesn't — but fixing the right ones does. The check is diagnostic; the fix is the work.