Sill vs Semrush 2026
Head-to-head comparison of two AI visibility platforms. Semrush (AI Visibility Toolkit (add-on to Semrush SEO platform)) versus Sill (AI visibility simulator with counterfactual analysis and daily SOV tracking across 6 platforms). Here is what each platform does, where each is stronger, and which one fits your team.
Company overview
| Sill | Semrush | |
|---|---|---|
| Focus | Purpose-built AI visibility simulator with counterfactual analysis, daily SOV tracking across 6 platforms, GEO recommendations | AI Visibility Toolkit add-on ($99/mo) to market-leading SEO platform; tracks AI visibility score, brand mentions, sentiment, and prompt tracking across 5 AI engines |
| Founded | 2024 | 2008 (AI Visibility Toolkit launched 2025) |
| HQ | United States | Boston, Massachusetts |
| Funding | Bootstrapped | Public company (NYSE: SEMR), $330M+ annual revenue |
| Customers | 139+ brands across 86 industries | 87,000+ paying customers (full platform); AI Visibility Toolkit adoption growing |
At a glance
| Sill | Semrush | |
|---|---|---|
| Starting price | $0/mo (free tier) | $99/mo add-on (requires Semrush subscription at $139.95+/mo) |
| Total minimum cost | $0/mo | $238.95/mo (Semrush Pro + AI Toolkit) |
| AI platforms tracked | 6 in all plans | 5 (ChatGPT, AI Overviews, AI Mode, Perplexity, Gemini) |
| Free tier | Yes (5 prompts, 6 platforms) | Free AI Brand Visibility Checker (limited) |
| Standalone product | Yes | No (requires active Semrush subscription) |
| Traditional SEO tools | No | Yes (full Semrush suite: keywords, backlinks, site audit, rank tracking) |
| GEO recommendations | Yes (748 across 62 brands) | General content recommendations |
| Counterfactual simulation | In development | No |
| AI site audit | No | Yes (checks if AI bots can crawl your content) |
| Regional drill-down | Limited | Yes (worldwide + specific regions) |
Feature comparison
| Feature | Sill | Semrush |
|---|---|---|
| AI SOV tracking | Daily across 6 platforms, all tiers | AI Visibility Score across 5 platforms |
| GEO recommendations | Actionable on-site fixes (87% on-site) | Not AI-specific recommendations |
| Prompt tracking | Yes | Yes (day-by-day visibility for specific prompts) |
| Competitor benchmarking | Yes | Yes |
| AI site audit / crawl check | No | Yes (checks AI bot accessibility) |
| Keyword research | No | Yes (25B+ keyword database) |
| Backlink analysis | No | Yes (43T+ backlinks database) |
| Traditional rank tracking | No | Yes (included in Semrush base) |
| Content marketing tools | No | Yes (SEO Writing Assistant, Topic Research) |
| Platform divergence analysis | Yes (55% of brands differ 10+ points) | Not a named feature |
| Additional domain cost | N/A (per plan) | $99/domain/month |
| Additional prompts | Included in plan tier | $60 per 50 additional prompts |
Pricing comparison
| Tier | Sill | Semrush |
|---|---|---|
| Entry | Free: $0/mo, 5 prompts, 6 platforms | $238.95/mo total (Semrush Pro $139.95 + AI Toolkit $99) |
| Mid | Basic: $90/mo, 120 prompts, 6 platforms | $338.95/mo total (Semrush Guru $249.95 + AI Toolkit $99 — adds historical data) |
| Upper | Pro: $225/mo, 360 prompts, 6 platforms | $538.95/mo total (Semrush Business $499.95 + AI Toolkit $99) |
| AI-only cost | $90/mo (all included) | $99/mo (add-on only, base subscription separate) |
| Additional domains | Included in plan | $99/domain/month |
| Per-prompt cost | ~$0.75/prompt (Basic) | $60 per 50 extra prompts ($1.20/prompt for overages) |
Which platform fits your team
Choose Sill if you:
- +AI visibility is your primary concern and you do not need traditional SEO tools
- +Want a standalone AI monitoring tool without requiring a $140+/mo SEO subscription
- +Need all 6 AI platforms tracked without paying for a base subscription first
- +Want actionable GEO-specific recommendations rather than general SEO guidance
- +Are building toward content attribution and experimentation for AI specifically
- +Need a free tier to evaluate before any financial commitment
Choose Semrush if you:
- +Already have a Semrush subscription and want AI visibility in the same dashboard
- +Need traditional SEO (keyword research, backlinks, rank tracking) alongside AI monitoring
- +Want AI site audit capabilities to check if AI bots can crawl your content
- +Need regional AI visibility drill-down by geography
- +Prefer a single platform for all search marketing (organic SEO + AI search)
- +Value the 25B+ keyword database and 43T+ backlink database alongside AI data
Verdict
Semrush and Sill serve different buying decisions. Semrush's AI Visibility Toolkit is the most cost-effective way to add AI monitoring to an existing SEO workflow — $99/mo on top of a subscription you already pay for. For teams already in the Semrush ecosystem, it is the path of least resistance. Sill is the right choice when AI visibility is the primary concern, not an add-on to traditional SEO. Sill's total cost for multi-platform AI monitoring ($90/mo for 120 prompts across 6 platforms) is significantly lower than the combined Semrush stack ($239+/mo minimum). Sill's GEO recommendations and counterfactual simulation approach provide AI-specific diagnostic depth that Semrush's toolkit, designed as a supplement to its SEO core, does not. The question is whether you need an AI visibility tool or an SEO suite with AI features. They are different products for different priorities.
See how AI search engines see your brand
Sill tracks AI Share of Voice daily across ChatGPT, Gemini, Google AI Overviews, Perplexity, and Claude. Start with 5 prompts free.
Get Your Report
Request your first analysis today to see where you stand.