DataFast is a web analytics tool made by the founder Marc Lou. Web analytics counts the visitors of a website, where they came from and what they did there. DataFast puts the focus on revenue attribution: it links each payment to the visit and the marketing channel that brought the customer.
The site owner adds a small tracking script to the website, by hand, through an npm package, or with plugins for WordPress, Shopify, Webflow and other platforms. The owner then connects a payment provider (Stripe, LemonSqueezy, Polar or Shopify, or the Payment API), and DataFast shows which channels, pages and search keywords bring paying customers. Custom goals, such as a signup or a download, and funnels show each visitor's path to a purchase. The default script uses cookies to recognize returning visitors; a cookieless script also exists. An API, a command-line tool and an MCP server let programs and AI agents query the data.
DataFast is a hosted service sold as a monthly or yearly subscription, priced by the number of tracked events per month, with a 14-day free trial.