Censys Data Collection


Censys collects data about hosts and websites through horizontal scans of the public IPv4 address space and the Alexa Top Million Domains. We validate, transform, and annotate this data with additional metadata (e.g., device model and geographic location) before we stream the records to a central database that maintains each host's state. We perform these scans from the University of Michigan using ZMap, ZGrab, and ZTag. Detailed information about our data collection is available in our research paper.

Looking for a protocol we don't scan or know how to identify a new type of device? Help us implement it and we'll add it to our roster.

Primary Datasets


We publish daily snapshots of what we know about each host, website, and certificate. These datasets contain structured, non-ephemeral JSON records that identify a host's configuration—similar to what is available in the search interface.



Regularly Scheduled Scans


Below are the regularly scheduled scans that power Censys. For each scan, we publish the host discovery scans and parsed application handshakes. We typically scan each protocol at least once weekly.


Historical Data


Below are scans we've run in the past, but no longer run regularly.