Web-based key generators, like random security-encryption-key-generator.aspx
This is where a dedicated comes into play. Specifically, a server-side tool (like an .aspx page) that pulls entropy from the operating system rather than a predictable math formula. Web-based key generators
Most online security key generators, including the one mentioned, typically offer the following options: Encryption Key Generator - AES Keys & IVs - RandomKeygen including the one mentioned