Comparison of the features offered for free by the supported CAs:

|      CA       | MaxLifetime | ECC Chain | Domain Count | Wildcard | IPv4 | IPv6 |  NotBefore  | NotAfter |  IDN  |  Test Server  |
|---------------|-------------|-----------|--------------|----------|----  |------|-------------|----------|-------|---------------|
| Let's Encrypt |      90     |     Full  |     100      |    Yes   |  No  |  No  |      No     |     No   |  Yes  |      Yes      |
| ZeroSSL       |      90     |     Full  |     100      |    Yes   |  No  |  No  |  Yes (+1d)  |    Yes   |  Yes  |       No      |
| Google        |      90     |  Partial  |     100      |    Yes   |  No  |  No  |      No     |    Yes   |   No  |      Yes      |
| Buypass       |     180     |  Partial  |       5      |     No   |  No  |  No  |      No     |     No   |  Yes  |      Yes      |
| SSL.com       |     104     |  Partial  |       2      |     No   |  No  |  No  |      No     |     No   |  Yes  |       No      |

Details for CAs servers are available here: [Server](https://github.com/acmesh-official/acme.sh/wiki/Server)