The Complete Website Audit Guide for Agencies

What is a website audit — and why should your agency care?

A website audit is a structured evaluation of a site across five categories: SEO, performance, security, mobile-friendliness, and accessibility. Each category gets a score from 0 to 100, converted to a letter grade (A through F).

For agencies, audits aren't just diagnostic tools. They're sales tools. A well-presented audit shows a prospect exactly what's broken on their site — and positions your agency as the team that can fix it.

The numbers back this up. Agencies that lead with a free audit convert prospects at 3-5x the rate of cold outreach alone. The audit does the selling for you: it creates urgency ("your site has 14 critical issues"), establishes authority ("here's exactly what to fix"), and generates a natural next step ("let's schedule a call to prioritize these").

The five audit categories explained

1. SEO (weight: 30%)

SEO is the largest component of any website audit because it directly impacts whether a site gets found at all. The checks include:

• Title tag: Present, unique, 30-65 characters. Google truncates anything longer in search results.
• Meta description: 120-160 characters. Not a ranking factor, but it controls click-through rate from SERPs.
• Heading hierarchy: One H1 per page, logical H2/H3 structure. Search engines use headings to understand content organization.
• Image alt tags: Every <img> should have descriptive alt text. This helps search engines index images and is essential for screen readers.
• Canonical URL: Prevents duplicate content issues when the same page is accessible via multiple URLs.
• Structured data: JSON-LD markup helps search engines display rich results (star ratings, FAQ dropdowns, product prices).
• Sitemap and robots.txt: A sitemap tells crawlers what to index. Robots.txt tells them what to skip.

A site scoring below 70 on SEO typically has missing meta tags, broken heading structure, and no structured data — all fixable within a day.

2. Performance (weight: 25%)

Performance directly impacts conversions. Google's own data shows that a 1-second delay in mobile load time reduces conversions by up to 20%. The key metrics:

• Largest Contentful Paint (LCP): How quickly the main content loads. Target: under 2.5 seconds.
• First Contentful Paint (FCP): Time to first visible content. Target: under 1.8 seconds.