All about Certificate

Censys

 https://censys.io/

Certificate | DNS | Dataset | IP | Network

Censys performs regular scans for common protocols (e.g., DNS, HTTP(S), SSH). Provides a search for TLS certificates.

Access is free, but requires registration. The website no longer provides free bulk access. Bulk access requires a commercial or a research license. The free access is limited to 1000 API calls per day.

@InProceedings{censys15,
    author = {Zakir Durumeric and David Adrian and Ariana Mirian and Michael Bailey and J. Alex Halderman},
    title = {A Search Engine Backed by {I}nternet-Wide Scanning},
    booktitle = {Proceedings of the 22nd {ACM} Conference on Computer and Communications Security},
    month = oct,
    year = 2015
}



Common CA Database

 https://www.ccadb.org/

Certificate

The Common CA Database provides links about general information about CAs and information about their root stores. This covers the root stores of Mozilla, Microsoft, and Google Chrome. Many other useful links are also available, for example, certificate searches and explorers.