Single Grain is a full-service growth agency, Geology is a software platform that productizes the GEO work an agency would otherwise bill against. If you want a team that runs paid, content, and SEO end to end with senior strategists in the loop, Single Grain is the right call. If you want measurement plus execution for AI search across ChatGPT, Perplexity, Gemini, Copilot, and Google AI Overviews, with same-week shipping cycles instead of quarterly retainers, Geology is built for that. Different motions, different price points, different speed.
At a glance
| Dimension | Geology | Single Grain |
|---|---|---|
| Best for | Mid-market and B2B teams that want to ship GEO fixes in-house | Brands that want a senior agency running growth end to end |
| AI platforms tracked | ChatGPT, Perplexity, Gemini, Copilot, Google AI Overviews | Tracked through partner tools as part of SEO work |
| Execution support | Yes. Page audits, prompt monitoring, content briefs, agentic optimization | Yes. Strategy, content, paid, and SEO via retainer |
| Pricing model | Subscription, transparent | Monthly retainer, custom scope |
| Time to first insight | Same-day audit | Discovery and onboarding cycle |
| Reporting | Self-serve dashboard plus exports | Account team reporting cadence |
| Best paired with | An in-house team that wants to ship | An exec sponsor with a retainer budget |
What Single Grain does
Single Grain is Eric Siu's growth agency, built around content marketing, paid acquisition, SEO, and conversion work for mid-market and enterprise brands. The agency is well known thanks to the Marketing School and Leveling Up podcasts, and the client list includes Salesforce, Amazon, and Uber over the years. The work is human-led: strategists, account managers, content teams, and paid media buyers run the playbook. Reviews on Clutch and G2 highlight senior expertise and the breadth of channels covered. The trade-off is the one common to retainers, the cycle time is set by the agency calendar, and the cost reflects a senior team running the work.
What Geology does differently
Geology productizes the measurement and execution loop that an agency normally bills against. The platform tracks brand visibility across the major answer engines, then turns the data into action: page audits flag the pages an AI is misreading, prompt management captures the queries your buyers actually run, the content workspace converts gaps into briefs your team can ship, and an agentic layer applies common fixes (schema, FAQ structure, internal linking) automatically. The result is a different cycle time. Where a retainer might queue a content sprint and a technical SEO ticket across two months, Geology lets a small in-house team validate, brief, fix, and re-measure inside a week. For teams with writers and developers who need a system to point them at the right work, the software path is faster.
Pricing
Single Grain runs a custom monthly retainer scoped to the channels you want covered, typically in the mid five figures per month for full-service growth. Geology is sold on a transparent subscription with public tiers, sized to sit alongside a small in-house team. For most mid-market companies, Geology lands at a fraction of the retainer because you are paying for the platform, not the people.
When Single Grain wins
If you do not have an in-house growth team and need senior strategists to run paid, content, and SEO on your behalf, Single Grain is a strong choice. The bench depth, the channel coverage, and the brand experience are real. Software cannot replace a senior media buyer or a strategist who has shipped this category before.
When Geology wins
If your team can write and ship but needs a system that points the work at the right pages, prompts, and platforms, Geology is the better fit. You get cross-platform AI search measurement plus a productized execution layer, and the cycle time runs in days. For teams that want to keep the strategy in-house, the software path is the cheaper, faster route.