Rebex SSH Check
Enter a hostname or IP address below to check the server's SSH capabilities:
This free SSH testing tool checks the configuration of given server accessible over internet. We don't ask you for any login or password, this service only returns information available during SSH handshake - notably supported encryption and MAC algorithms, and an overview of offered server public keys.
Changelog
2026-10-14: New "Quantum-safe" security level for post-quantum algorithms; recognition of post-quantum ML-DSA host key algorithms (pure and hybrid), pure ML-KEM key exchange and many more legacy and vendor-specific algorithms
2025-12-18: Recognition of post-quantum key exchange algorithms (ML-KEM, sntrup761) and more host key algorithms
2024-04-04: Showing a confirmation when the server is not vulnerable to Terrapin
2024-03-18: Terrapin vulnerability detection
2024-03-15: Technological update
2022-11-14: Technological update
2022-10-24: IPv6 support
2022-09-30: Support for multiple IPs per hostname
2022-07-25: Technological update
2020-10-06: Cache clearing support
2017-06-29: Adding support for rsa-sha2-256, rsa-sha2-512 and ssh-rsa-sha256@ssh.com keys.
2017-06-21: SshCheck should no longer crash when there is no common SSH algorithm between us and the queried server (as was the case with e.g. chacha20-poly1305).
2017-06-19: Please note that IPv6 queries are still not functional. We're trying to fix this. Another issue is querying servers with only chacha20-poly1305 and aes-gcm algorithms. We're working on that as well.
2017-06-16: Decreased cache expiry to 10 seconds. Reclassified security level of some algorithms.