How to use SimilarSites for your startup
TL;DR
SimilarSites is a free tool from SimilarGroup, powered by Similarweb data, that lists the websites most similar to any domain you enter. You cannot submit or add a site: a page for your domain appears only once Similarweb's data covers it. Founders use it for free competitor research and to see which sites show up next to theirs.
What is SimilarSites?
SimilarSites (similarsites.com) has run since 2009 and is now mainly a Chrome extension plus a set of public pages. Each page at similarsites.com/site/yourdomain.com shows:
- a short description of the site;
- monthly visits and a category rank from Similarweb;
- a list of similar sites with a similarity score in percent;
- the categories that the site's visitors also browse, plus related topics.
Its About page says the matches come from content, keyword density, topic tags, the sites people visit next, and link analysis. The homepage itself offers the extension download and a few popular sites; the per-domain pages are where the data lives.
Who should use SimilarSites?
- Founders mapping their competitors: enter the market leader's domain and get a ranked list of alternatives in seconds.
- Marketers looking for places where their audience already spends time, for partnerships, guest posts or ads.
- Startups with steady traffic that want to see which brands their visitors also browse.
- Skip it if you need a listing or a backlink. New and small sites get the message "That site either doesn't exist or is not yet part of our database", and there is no form to change that.
How much does SimilarSites cost?
SimilarSites is free, both on the website and as the Chrome extension, with no paid plan. The traffic numbers come from Similarweb, which sells deeper data through its own paid plans.
How do you get your startup on SimilarSites?
- Check whether your page exists: open similarsites.com/site/ followed by your domain, such as similarsites.com/site/femaleswitch.com.
- If you see "not yet part of our database", build traffic first. SimilarSites has no submission form; it adds domains from Similarweb's data set.
- Claim your domain on Similarweb and connect Google Analytics 4. Similarweb's help pages say free users can do this publicly, which marks your traffic numbers as verified on Similarweb. We found no statement that this adds a site to SimilarSites, so treat it as a step for accurate data.
- To fix wrong information, write to contact@similarsites.com. A Site Removal Request form exists for owners who want their page taken down.
Tips to get more out of SimilarSites
- Run your three biggest competitors through it and note every site above 70% similarity. That list is your real competitive set, including names you missed.
- Read the "people who also visited" categories to learn what else your buyers care about, then plan content and partnerships around it.
- Recheck your own page each quarter once it exists; a new similar site in your list signals a new competitor.
- Pair it with directories that accept submissions, since SimilarSites only reflects traffic you already have.
Our verdict
SimilarSites is a free, fast competitor research tool, and it does not accept startup submissions. Use it to study your market, and spend your listing time on directories where you control the profile.
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