About the data gathered

In our latest scan of Dec 2023:

About data deduplication and network correlation

Data deduplication and network correlation are important things that need to be done in order to get reliable statistics. Unfortunately they are also time consuming tasks.

Server deduplication

We need to deduplicate data: IRC servers may listen on multiple IP addresses, some even in totally different netblocks (yes, really). It is very important that these duplicates are filtered out. Example: 10 servers even listened on 500+ IP addresses in total!
On the other hand server names and network names are not unique, so these cannot be used as decissive factors. For example in 2017 there were 900+ servers with the network names 'ROXnet' and 'debian'. These are default network names in configuration files, hence the high number of matches. They are obviously not two big networks.
Fortunately we have come up with a reliable way to deduplicate server data using things like: server names, network names, software version, uptime information and more. If all these are the same then it's extremely likely it's the same server. We filtered out thousands of duplicates using this method.

Network correlation

Networks running services are easy to correlate, hence the user counts on the Services page.
However, knowing which servers belong to which network on networks without central services is not so easy to detect. Some statistics such as user and channel counts can only be published after this is done, otherwise they would not be reliable. There's no room for error: if you fail to detect servers belonging to the same network you will very quickly count users and channels twice or more. This will cause counts to be off by tens of thousands, which is not acceptable.
The 2016 scan contains insufficient data to do proper network correlation. Servers on the same network turned out to have different network name. Other distinct networks shared the same network names. This wouldn't be much of a problem if not also a significant amount of servers blocked /MAP and /LINKS.
From the 2017 scan onward additional data was gathered, but no significant effort was made to do network correlation for networks without services.

SSL/TLS statistics

IRCStats started scanning and publishing results in 2016. However, the first year SSL/TLS data was gathered was 2017. The years 2017/2018/2019 the scan was done on port 6667 on the entire IPv4 address range. After finding the IRC servers that listened on port 6667, the servers listening on port 6667 were scanned for port 6697 and SSL/TLS data was gathered.
In the year 2020 it was done differently with the entire IPv4 internet scanned on BOTH port 6667 and 6697, therefore picking up IRC Servers that don't listen on port 6667 (IRC plaintext). This naturally has a strong effect on the SSL/TLS statistics in particular from the year 2020 (and onward), as it turned out that in Dec 2020 about 10% of the IRC Servers only listen on port 6697 and not on 6667.


Scanning the entire IPv6 address space is impossible (it would be 2 to the power of 128, so 340282366920938463463374607431768211456 IP addresses). Hence, we use the IPv6 hitlist plus we mass-resolve all IRC server hostnames from previous year and use those AAAA records. The first IPv6 scan happened in the year 2022.

I want to see more data / more graphs!

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Note that only after network correlation is done, reliable statistics can be published with user and channel counts. This is hard, so we'll see when that happens.
Important: we will not give away data that may identify individual networks, servers or users.

Can I get a copy of the data set?

These data sets are currently available. If you use them, please credit ircstats.org. We will not give out a copy of the raw data. See the About page for our strict rules on privacy.