How to Do a Site Audit with Semrush in 2026: Fix SEO Issues Fast

Your site could be bleeding traffic right now because of broken links, duplicate meta tags, or crawl errors you have never seen. A proper site audit finds those problems in under 30 minutes and gives you a clear list of exactly what to fix. I have run audits on dozens of sites using Semrush, and this walkthrough covers every step without wasting your time.

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What You Need Before Starting

You need a Semrush account. The free plan limits you to 100 pages per crawl, which works for small sites. If you run anything larger, the Pro plan at $139/month is worth it for unlimited crawls and the full issue breakdown.

You also need access to Google Search Console and Google Analytics. Semrush pulls in data from both when you connect them, and the combined view is significantly more useful than crawl data alone. Have your login credentials ready before you begin.

Finally, make sure you know your site's URL structure. If you run a WordPress site with both www and non-www versions, pick one canonical version now so the audit does not split your data across two properties.

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Step-by-Step Site Audit Walkthrough

Step 1: Create a New Project in Semrush

Log into Semrush and click "Projects" in the left sidebar. Hit "Create project," enter your domain, and give it a name. Semrush will prompt you to set up several tools at once, but skip everything except Site Audit for now. Keep it focused.

Step 2: Configure Your Crawl Settings

Click "Set up" under the Site Audit section. Set the crawl limit to match your actual page count, not the default. If your site has 200 pages, set the limit to 250 to give it room. Under "Crawl source," select "Website" and enter your homepage URL.

Check the "Crawl JavaScript" box if your site uses React, Vue, or any JavaScript-rendered content. A lot of people skip this and then wonder why their audit misses half their pages.

Step 3: Allow Bot Access

Semrush uses its own crawler bot called SemrushBot. Go to your robots.txt file and confirm it is not blocking this bot. If you are on WordPress, use a plugin like Yoast to check quickly. A blocked bot means an incomplete audit, and incomplete data leads to bad decisions.

Step 4: Connect Google Search Console

Inside the project settings, find the "Google Search Console" integration tab. Connect your GSC account and select the matching property. This pulls in your actual impressions and click data, so Semrush can flag pages that have technical issues AND poor performance at the same time.

Step 5: Start the Crawl

Hit "Start Site Audit." Depending on your site size, the crawl takes between 5 minutes and several hours. A 500-page site typically finishes in under 20 minutes. You will get an email notification when it is done.

Step 6: Read the Site Health Score

Once the audit finishes, Semrush shows you a Site Health Score between 0 and 100. Anything below 80 needs immediate attention. Do not obsess over hitting 100. Some flagged issues are intentional choices, like blocking certain pages from indexing.

Step 7: Prioritize by Issue Category

Semrush breaks issues into three tiers: Errors, Warnings, and Notices. Fix Errors first, always. These are the problems actively hurting your crawlability and indexing. Warnings matter but will not tank your rankings overnight. Notices are mostly informational.

Step 8: Fix Crawlability and Indexing Errors

Click into the "Errors" section. The most common ones I see are broken internal links, pages blocked by robots.txt that should be crawlable, and redirect chains. Export the full list as a CSV. Send broken link fixes to your developer or handle them yourself in your CMS.

Step 9: Fix On-Page SEO Issues

After crawlability errors, move to missing or duplicate title tags and meta descriptions. Semrush lists every affected URL. If you have a blog with 80 posts, some of these duplicates are probably auto-generated by your theme or category pages.

This is where content tools help. I use Surfer SEO to rewrite and optimize metadata quickly, especially for pages that are close to ranking but underperforming. For drafting new meta descriptions at scale, Jasper and Writesonic both cut the time down considerably.

Step 10: Re-crawl and Confirm Fixes

After making changes, go back to Semrush and click "Re-run campaign." Compare the new score against the old one. Semrush shows a progress view so you can see exactly which issues disappeared and which are still open. This step is non-negotiable. You need confirmation, not assumptions.

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Quick Reference Table

Step	Action	Time Needed
1	Create a new Semrush project	3 minutes
2	Configure crawl settings	5 minutes
3	Check robots.txt for bot access	5 minutes
4	Connect Google Search Console	5 minutes
5	Start the crawl	5 to 60 minutes
6	Review Site Health Score	5 minutes
7	Prioritize errors vs. warnings	10 minutes
8	Fix crawlability errors	30 to 90 minutes
9	Fix on-page SEO issues	60 to 120 minutes
10	Re-crawl and verify fixes	10 minutes

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Common Mistakes to Avoid

Running the audit on the wrong URL. If your site redirects www to non-www, audit the canonical version. Auditing the redirect version gives you noise, not real data.

Ignoring the crawl depth setting. Semrush defaults to crawling only a few levels deep. If your site buries content five clicks from the homepage, increase the crawl depth or those pages will not appear in your report at all.

Treating all warnings as urgent. Semrush will flag things like images without alt text as warnings. These matter for accessibility and SEO, but fixing them will not rescue a site with 404 errors and redirect loops. Sequence matters.

Fixing issues without documenting them. Keep a running log of what you changed and when. When you re-crawl and the score improves, you want to know exactly what drove the change. This is especially important for client work.

Running audits too infrequently. One audit is a snapshot, not a system. I set Semrush to run scheduled crawls every week. Sites break in ways you do not expect, and catching a new redirect error in week two beats finding it three months later after rankings have already dropped.

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Pro Tips

Use the Compare Crawls feature. After your second audit, Semrush lets you compare it against the first. You can see exactly which new issues appeared and which ones you resolved. This is one of the most underused features in the entire tool.

Filter by page template. If you run an ecommerce site, filter the audit results by URL pattern. Group all your product pages together, all category pages together, and fix issues by template type instead of one page at a time. This saves hours.

Cross-reference with GSC Performance data. Pages that have technical errors AND low click-through rates are your highest-priority targets. A page with a missing title tag that ranks on page two is a fast win. Fix the tag, watch the CTR jump.

Use AI tools to scale content fixes. When Semrush flags 60 pages with thin content, writing new sections manually is not realistic. I run those URLs through Copy.ai to generate first drafts and then edit them. The combination of Semrush for diagnosis and an AI writing tool for execution cuts the turnaround from weeks to days.

Schedule audits to run before and after major site changes. Launching a redesign or migrating to a new CMS without running an audit first is one of the fastest ways to lose rankings. Run an audit before the change, export the data, then run one again after and compare.

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Bottom Line

A Semrush site audit is the most efficient way to find what is quietly killing your SEO performance. The tool surfaces problems you would never catch manually, and the fix-and-verify loop it creates keeps your site clean over time.

The audit itself takes less than an hour to set up and run. Fixing what you find takes longer, but you will not be guessing. You will have a prioritized list with URLs, issue types, and recommendations all in one place.

Start with Semrush, run your first audit this week, and fix your Errors before anything else. That single step alone puts you ahead of most sites in your niche.