Several tools can assist in tracking direct revenue from email marketing: 1. Google Analytics: By using UTM parameters to track email links, businesses can see the direct impact of their email campaigns on website traffic and sales. 2. Email Service Providers (ESPs): Most ESPs like Mailchimp, Constant Contact, and Klaviyo offer built-in analytics to track revenue. 3. CRM Systems: Customer Relationship Management (CRM) systems like Salesforce can integrate with email marketing platforms to track and analyze sales data.