Semrush Site Audit is genuinely good. It crawls your entire site, flags 140+ issue types, tracks health score over time, and integrates with the rest of Semrush's ecosystem. If you're already paying for Semrush, the site audit module is an excellent bonus. The problem is when you're paying $139.95/month primarily for site auditing.
That's like buying a Swiss Army knife because you need scissors. The scissors work fine, but you're also paying for the corkscrew, the toothpick, and the tiny saw you'll never touch. Most teams use maybe 20% of Semrush's features regularly.
The other gap: Semrush Site Audit is purely technical. It catches broken links, slow pages, missing alt tags, and crawlability issues. It does not evaluate whether your pages actually persuade visitors to take action. For conversion optimization, you need a different class of tool entirely.
I evaluated five alternatives — some cheaper, some more focused, some covering ground that Semrush doesn't touch. Here's how they stack up for teams that need auditing without the all-in-one tax.