Background: Individuals with kidney diseases have increased risk of cardiovascular disease and death. Online cardiovascular risk assessment tools can educate patients on risks and modifiable factors. Since patients have variable health literacy, we evaluated the readability, understandability and actionability of publicly available online cardiovascular risk assessment tools. Methods: We systematically searched, reviewed, characterized and assessed English-language cardiovascular risk assessment tools online for readability (Flesch-Kincaid Grade Level (FKGL) score), understandability and actionability (Patient Education Materials Assessment Tool for printable materials (PEMAT-P)). Results: After screening 969 websites, 69 websites employing 76 risk tools were included. The most frequently used tools were the Framingham risk score (n= 13) and the Atherosclerotic Cardiovascular Disease score (n= 12), Most tools were intended for the general population and estimated the 10-year incident cardiovascular risk. Patient education was provided as targets for blood pressure (n= 17), lipids (n= 15), or glucose (n= 5); and advice regarding diet (n= 18), exercise (n= 19), and smoking cessation (n= 20). The median FKGL, PEMAT- understandability and actionability scores were 6.2 (4.7, 8.5), 84.6% (76.9%, 89.2%) and 60% (40%, 60%), respectively. Conclusion: The online cardiovascular risk tools were generally easy to read and understand, but only a third provided education on risk modification. Judicious selection of an online cardiovascular risk assessment tool may help patients in self-management.