An SEO company tracks key performance indicators (KPIs) across several categories, because no single number explains whether a search strategy is working. Visibility metrics show whether more people can find you, traffic metrics show whether they arrive, engagement and conversion metrics show whether that traffic turns into business, and technical and backlink metrics show whether the site can sustain those results. A capable agency reports on all of these so you can see both the activity and the outcome.
Visibility metrics
Visibility metrics measure how often and how prominently your site appears in search results. The most familiar is keyword rankings, the positions your pages hold for terms you target. Because rankings now vary by location, device, and personalization, agencies pair them with impressions, the number of times your listings were shown, which comes directly from Google Search Console. They also track share of voice, your visibility compared to competitors across a group of topics rather than a single keyword. Many agencies now add visibility in featured snippets and citations in AI-generated answers, since search engines and answer tools like ChatGPT, Gemini, and Perplexity increasingly surface sources directly. Together these metrics show whether your presence in search is expanding.
Traffic metrics
Traffic metrics measure how many people reach your site from organic search. Organic sessions, reported in GA4, is the core figure, and it is often split into branded traffic (people searching your name) and non-branded traffic (people searching for what you offer). Agencies also look at traffic quality, not just volume, by separating engaged sessions from bounces and bot activity. Click-through rate, the share of impressions that result in a click, helps explain whether your titles and descriptions are persuasive. Rising impressions with a flat click-through rate, for example, points to a presentation problem rather than a ranking problem.
Engagement metrics
Engagement metrics show what visitors do after they arrive. Common measures include engagement rate, average engagement time, pages per session, and the share of returning visitors. These signals tell an SEO company whether the content matches what searchers expected and whether the page experience encourages people to stay and explore. Weak engagement often points to a content or relevance issue that purely traffic-focused reporting would miss.
Conversion and revenue metrics
Conversions tie SEO to business results, so a serious agency treats them as central rather than optional. Depending on your goals, conversions may include form submissions, calls, sign-ups, purchases, or qualified leads. Agencies track the organic conversion rate, the volume of conversions from search, and, where the data is available, the revenue and return on investment attributed to organic channels. For businesses that can measure it, customer acquisition cost and customer lifetime value add further context. These metrics answer the question that rankings alone cannot: is search driving real value?
Technical health metrics
Technical metrics confirm that the site can be crawled, indexed, and used easily. Agencies monitor indexation and crawl coverage, crawl errors, broken links, and mobile usability. They also track Core Web Vitals, a set of page experience measures that includes Largest Contentful Paint for loading speed and Interaction to Next Paint for responsiveness. Poor technical health can quietly limit results no matter how strong the content is, so these KPIs act as an early warning system.
Backlink profile metrics
Backlinks remain a meaningful ranking factor, so an SEO company tracks the size and quality of your link profile. This includes the number of referring domains, the authority of those domains, the relevance of linking sites, the mix of anchor text, and referral traffic from links. Agencies watch for unnatural or low-quality links as well, since these can create risk rather than benefit. The goal is steady growth in credible, relevant links rather than raw volume.
A complete SEO report covers all of these categories. When you evaluate an agency, ask which KPIs they will track for your business, how they will report them, and how each one connects to your goals. A company that explains the full picture, rather than a few flattering numbers, is one you can hold accountable.