Keywords Everywhere is a popular browser extension in the SEO space. It shows the search volume for keywords on Google alongside a list of related search terms. More than one million people have installed the extension.
In 2019 Keywords Everywhere started charging for its service.
Surfer SEO quickly launched a free extension, Keyword Surfer. The extension offered much the same functionality as Keywords Everywhere. Here it is at work.

Over 400,000+ people have installed Keyword Surfer on Chrome.
The extension is the primary customer acquisition channel for Surfer, which is now at $10 million ARR. It’s a nice example of making the most of an emerging gap in the market and the power of a good freemium browser extension.

Nico is the founder of Crunch Marketing, a SaaS marketing agency. He works with enterprise SaaS clients like Writer, Right Inbox, and Surfer SEO, helping them scale lead generation globally across EMEA, APAC, and other regions.