The best Cloud Computing alternative to Nessus is Qualys Cloud Platform. If that doesn't work for you, our users have ranked more than 50 alternatives to Nessus, but unfortunately only two of them are Cloud Computing Services.
Nessus alternatives are mainly Cloud Computing Services, but if you're looking for
Vulnerability Scanners you can filter on that. Other popular filters include
Open Source and
Free. You can also filter by region, for example
EU-based alternatives if you prefer software developed in the European Union. These are just examples - use the filter bar below to find more specific alternatives to Nessus.