Semrush vs Similarweb: SEO Suite or Market Intelligence?

The short answer

Semrush and Similarweb overlap on competitor traffic, keywords and AI visibility, but they come from opposite ends. Semrush is an SEO suite with a traffic toolkit added; Similarweb is a market intelligence platform with SEO tools added. Choose Semrush to run SEO day to day: site audits, rank tracking, keyword research and AI prompt tracking, with published prices from US$139 a month ^[1]. Choose Similarweb to study markets and competitors' traffic across channels, apps and retail, with prices from sales. If you only want traffic data, Semrush's Traffic & Market toolkit costs US$289 a month.

This comparison uses each company's own pages, read from the US on 12 October 2026. Similarweb publishes no prices, so the pricing part is necessarily one-sided. Everything else is matched claim for claim, and where the two vendors make claims about size or accuracy, we flag them as vendor claims rather than settled facts.

Two different companies that meet in the middle

Similarweb describes itself as a digital intelligence platform with Web, Search, App, Retail, Sales and Stock Intelligence, plus data as a service. Semrush sells an SEO platform with separate toolkits for AI visibility, local, content, social, advertising, PR and traffic. Their overlap is Similarweb Web Intelligence against Semrush's SEO plans plus Traffic & Market.

Outside that overlap they hardly compete. Nobody buys Similarweb to fix broken links or track 500 local keywords, and nobody buys Semrush to size an Amazon category or follow app downloads in Brazil. Keep that split in mind through every section below, because most of the "wins" on each side follow from it. The question is less which tool is better and more which question you need answered most often: how to rank, or how a market and its players are moving.

Pricing: a price list against a sales call

What Semrush charges

Semrush lists every plan: SEO US$139, Starter US$199, Pro+ US$299 and Advanced US$549 a month. It shows both monthly and annual prices and charges the year upfront, and it publishes extra-user prices for its SEO plans, from US$45 a month. Traffic & Market Pro costs US$289 a month, billed annually, on the pricing page ^[2], although the help center lists the same US$289 as monthly. Pro includes one user seat and 3,000 requests a day; a custom plan adds team access and the API, and the pricing page puts extra users at contact us.

What Similarweb shows instead

Similarweb's pricing page shows packages but no figures, and sends businesses to sales ^[3]. It mentions self-service packages for individuals, entrepreneurs and small teams, without prices in the text we read. It names Competitive Intelligence and Competitive Intelligence & SEO packages, the second adding SEO tools. Its package list includes up to 37 months of history, 100+ country-level views, managed services, conversion analysis, AI Studio, data feeds, APIs, MCP and SSO, and premium features need a custom package.

That shapes the buying process. A Semrush buyer can compare plans, start a trial and pay by card in minutes, while a Similarweb business buyer should expect a demo, a quote and a contract. Similarweb asks customers to email support to switch to annual billing. With Semrush you know the saving before you buy. With Similarweb you negotiate it. Our Semrush pricing guide breaks down every plan.

Seats and leaving

Semrush's Traffic & Market Pro includes one user seat. Similarweb's AI Studio is pitched for teams from 3 users to 30+, but Similarweb does not publish seat prices. Leaving works differently too. Similarweb's Entrepreneurs packages cancel inside the account, while business plans follow the contract. Semrush cancels through a form and refunds only first annual purchases within 7 days, so check the date before you commit to a year.

What you can try for free

Semrush's free plan gives 10 reports a day, but Traffic & Market shows only sample domains to free users. Similarweb's free traffic checker allows three searches a day, and its browser extension is free without an account. The extension shows monthly visits, bounce rate, pages per session and visit duration, AI chatbot traffic, top AI prompts, keywords with estimated clicks and CPC, global and category rank, channel mix and geography. It works on Chrome, Edge, Firefox and Opera. For a quick traffic look, Similarweb's free tools go further.

Semrush answers on organic search. Its free tools page lists a website traffic checker, an AI traffic checker and an AI search visibility checker that need no sign-up, plus a keyword tool, a keyword search volume checker, a keyword rank checker and a SERP checker. A free account adds 10 Domain Overview lookups a day with organic traffic and AI visibility metrics, and 10 keyword lookups a day. Similarweb offers a free keyword research tool with volume, competition and trend data. Both are samples. For organic search specifically, Semrush's free data is richer.

Trials differ as well. Semrush offers 7-day trials on its plans and toolkits, once per account, with exports blocked, and a Traffic & Market trial is available only if you never had one or a subscription. Similarweb offers a free trial and lets support switch you between product trials. It does not state the trial's length there.

Where the traffic numbers come from

Two different methods

Semrush says Traffic & Market rests on clickstream data from proprietary and third-party sources, modeled from the behavior of over 200 million internet users and more than a hundred apps and browser extensions. It is an estimate for other sites, Semrush stresses, not a replacement for Google Analytics. Similarweb names four sources: direct measurement from sites that share their analytics, a contributory network of consumer products, partnerships, and public data extraction ^[4]. Elsewhere it adds a large global panel and machine learning that calibrates the inputs. Direct measurement is the notable difference. Some sites share real numbers.

Accuracy, sizes and coverage

Similarweb cites a SparkToro study that found its traffic estimates closest to Google Analytics, ahead of Semrush and Ahrefs, mostly for sites with 5,000 to 100,000 monthly users. Semrush cites its own study of search volume accuracy. Both claims come from the vendors' pages. Semrush itself says its traffic numbers are built to be compared between sites inside the tool, and that is the honest way to use either vendor: rank competitors against each other rather than quote one estimate as fact.

The size claims follow the same pattern. Similarweb claims data on 100 million websites, 6 billion keywords and 4 million apps, and coverage of 190 countries. Semrush claims 28 billion+ keywords, 142 keyword databases and 808 million domain profiles, so its keyword base is several times larger by its own count. For traffic in smaller markets, test both tools on a site you know.

A test you can run for free

Pick a site whose Google Analytics you can see. Look it up in Similarweb's free traffic checker and in Semrush's Domain Overview on a free account, then compare both with the real monthly visits. Repeat for two more sites. The closer tool, for your niche, is the one to pay for. It costs nothing.

SEO work: keywords, rankings, audits and links

Keyword research and freshness

Semrush's keyword tools include Keyword Overview, the Keyword Magic Tool, Keyword Gap for five domains and Keyword Strategy Builder. Similarweb offers a Keyword Generator across Google, Amazon and YouTube, with over 5 billion keywords, a Keyword Gap, and metrics such as zero-click rate. On freshness, Similarweb's SEO page promises keyword data from the last 28 days, and its keyword page says it updates keyword data daily. Semrush's keyword research page lists monthly data refreshes for its database. For spotting new search trends, Similarweb's cadence is quicker.

Rank tracking

Similarweb's Rank Tracker tracks up to 200,000 keywords daily, by device and down to ZIP code, with click data and AI Overviews. Semrush tracks 500 to 5,000 keywords on its published plans, plus ChatGPT Search and Google AI Mode, and its Position Tracking updates daily only for the keywords you track. Similarweb monitors five competitors closely; Semrush allows 20 per campaign. Both backfill history for competitors you add. Similarweb shows a universal rank and a weighted average position, while Semrush reports Visibility and, on Business, Share of Voice. The approaches are close. The keyword ceiling is the real difference. Our Position Tracking guide covers Semrush's side in detail.

Site audits and backlinks

Similarweb's Site Audit checks 300+ factors on its own servers and includes Majestic backlink data and a Logs.io account, but it is available to account-managed customers. It adds a traffic funnel report, share links for clients and saved crawls for trends, and can audit any website, with deeper crawls for sites connected to Search Console. Semrush's Site Audit runs 140+ checks and AI bot access tests, from 100 pages free to 1 million a month on Business, and adds Trello cards and crawl comparisons.

On backlinks, Semrush runs its own database, which its trial guide puts at more than 43 trillion links. Similarweb's Backlink Analytics claims 360 trillion links and 200 million domains, with new data every day. Those are vendor counts. Compare referring domains for your own site in both.

Market, audience and competitor research

This is Similarweb's home ground. Semrush's Market Overview estimates total and serviceable market size, shows market consolidation and plots competitors on a growth quadrant. Similarweb's market research covers market size, entry difficulty, brand strength and rising and declining players, and it reaches into traffic, apps, Amazon and company data. On paper the market tools match. In scope, Similarweb is broader, and its AI Studio answers market questions in plain language.

Audience questions lean the same way. Similarweb analyzes audience overlap, affinities and behavior across competing brands, while Semrush's Traffic & Market toolkit focuses on traffic volume, channels, top pages, conversions and market share. For a question such as which sites your buyers also visit, Similarweb is the tool built for it. On channel mix, the two are close: Semrush splits traffic by AI, organic search, paid search, paid social, organic social, referral, email and display, and Similarweb shows the same kind of mix plus geography and engagement.

Apps and Amazon settle it for some buyers. Similarweb covers 4 million apps and offers Amazon data; AI Studio draws on 18 Amazon datasets across six marketplaces. Semrush's toolkits center on websites and search. For a brand that sells mainly through apps or Amazon, Similarweb answers questions Semrush's web data cannot.

For paid search and monitoring, both cover the basics. Similarweb's PPC tools monitor competitors' paid search, benchmark CPC and keyword coverage, and track paid share. Semrush sells an Advertising toolkit at US$99 or US$220 a month, and only its paid tools carry a public price. Semrush's Competitor Monitoring alerts you to rivals' new blog posts, Google Search ads, new pages and Facebook and Instagram posts; Similarweb adds press and traffic shifts to its alerts. Both also track SERP volatility, with Similarweb's free SERP Seismograph and Semrush's Sensor.

AI tools, MCP and the API

AI visibility and AI traffic

Semrush tracks brand mentions in ChatGPT, Google AI, Gemini and Perplexity, from US$99 a month per domain on annual billing. Similarweb sells AI Search Intelligence with brand visibility, citation, prompt and sentiment analysis, without a published price. For referrals, Semrush's AI Traffic dashboard estimates traffic from 21 AI services to any domain, inside Traffic & Market. Similarweb's free AI Traffic Checker shows referrals from ChatGPT, Perplexity, Gemini and Claude. For a free look at AI referrals, start with Similarweb. Our Semrush AI guide covers the paid side.

Assistants and MCP

Semrush's Copilot gives SEO suggestions from your projects and is part of every subscription. Similarweb's AI Studio answers questions, writes deep research reports and builds dashboards across all its data, but it is enterprise-only, with consumption-based credits. Copilot is narrower but included. For a small team, an assistant that already sits inside the subscription and points to the next fix is worth more than one that needs an enterprise contract first. Both offer MCP servers. Semrush includes 50,000 MCP units on Starter and Pro+ and connects ChatGPT, Claude, Gemini and Perplexity; Similarweb's supports Claude, ChatGPT and Copilot. Only Semrush states how many queries a plan includes.

API and historical data

Semrush's Standard API is an add-on for its top SEO tier, and its Trends API covers traffic data with 10,000 requests a month by default, can monitor up to 200 domains at once and goes back to 2017. Similarweb sells its API in custom business packages or as a standalone product, priced by sales, and offers up to 37 months of history as an add-on. For long market trends, Semrush's traffic API reaches further back, by its own description.

Reputation and scale claims

Similarweb says G2 named it a market leader in Enterprise SEO Tools, Enterprise Competitive Intelligence Tools, Market Intelligence Tools and three other categories, and Semrush is also well rated on G2. Badges are marketing. Read recent reviews from companies your size. The scale claims need the same care: Similarweb says it has over 10,000 customers, including 200+ of the Fortune 500, while Semrush says 28 million marketers have used it and 35% of the Fortune 500 chose it. The figures measure different things, paying companies against all users ever. Neither is audited.

Which one to choose

Choose Semrush if you are a small or mid-size business, a freelancer or an agency doing SEO work, and you want a published price, a free plan and daily rank tracking with AI prompts. A team that needs competitor traffic only occasionally can add Traffic & Market for the months it matters. Choose Similarweb if you are a market researcher, an investor, or an ecommerce or app team that needs traffic data across web, apps and Amazon, or a large company that wants AI Studio, data feeds and managed services. If you expect to negotiate an annual contract anyway, the missing price list is normal.

Some teams run both: Semrush for SEO and Similarweb for market sizing. The overlap then sits in keyword data and traffic estimates, which will not match. Pick one source of truth per metric. Keep traffic estimates from one vendor in reports, or the numbers will contradict each other.

The bottom line

Semrush is the better SEO tool and the only one of the two with public prices. Similarweb is the better market lens, with direct measurement and coverage beyond websites. If your question is how to rank, buy Semrush. If your question is how big a market is and who is winning it, talk to Similarweb's sales team. Either way, run the free side-by-side test on a site you know before you pay.