![[LISTSERV - the mailing list management classic]](https://www.lsoft.com/images/HDR-LISTSERV-sm.gif)
There are many possible ways to measure the relative "importance" or "size" of LISTSERV sites: number of lists, number of subscribers, number of messages delivered, etc. In most cases, the number of messages delivered is used to rank mailing list managers, because it is the most accurate measurement of the amount of activity on the server. But, depending on what you are looking for, other variables may be more appropriate. There are currently three LISTSERV "Top 20" lists, ranking the various servers according to:
In addition, you can view a list of the Top 20 lists in the network (by number of subscribers).
The statistics are gathered daily by a monitor at L-Soft which polls all the LISTSERV sites that participate in the "open" LISTSERV network over the worldwide Internet. Corporate servers operating in a "closed" environment are not included.
The statistics are organized in monthly reports. The message volume figures are a flat average of the accumulated traffic for the entire month. Thus, a server that delivers 300,000 messages per month will show a daily average of 10,000 messages. In practice, there is a lot less traffic during the weekend, and even during business days there can be significant fluctuations (~30%). The list statistics (number of lists, number of subscribers, largest lists in the network) are measured as of the last day in the month.
For the current month, the message volume figures are averaged based on the number of days that have elapsed. In practice, the figures are not very meaningful in the first few days, especially if the month starts on a weekend. In that case it is best to refer to the previous month for more accurate figures.
A fourth "Top 20" list is available for the more technically oriented: Number of messages generated by the server. This corresponds to the number of mail messages created by the server while processing postings to its mailing lists. LISTSERV delivers its mail using an intelligent mail delivery function called DISTRIBUTE, which improves mail delivery times and reduces bandwidth usage by spreading the delivery chore over scores of participating servers. Each of these servers processes the recipients for its service area (typically its organization or campus). In most cases, DISTRIBUTE simply alters the manner in which the mail is delivered, and the number of messages forwarded to other sites for optimized delivery is roughly equal to the number of messages received by other sites for the same purpose. In some cases, however, this is not the case, either because the server elected to serve a much wider service area than its own organization, or because it is explicitly forwarding all its deliveries to another machine (for instance, many mainframe-based servers forward their mail to a workstation or PC for delivery).
Pos Recipients Site --- ---------- ---- 1 656630 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 244206 LISTSERV.LIV.AC.UK (Linux 3.10.0) 3 243228 LISTS.PSU.EDU (Linux 3.10.0) 4 187234 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 5 172974 LISTSERV.TAMU.EDU (Linux 3.0.101) 6 152609 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.25.1.el7.x86_64) 7 126884 LISTS.UFL.EDU (Linux 2.6.32) 8 123654 LISTS.HAWAII.EDU (Linux 3.10.0-1160.31.1.el7.x86_64) 9 121722 LISTSERV.TDBANK.CA (Windows Server 2012 R2 Datacenter x64 Edition) 10 117225 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 11 113821 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 12 106435 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 13 104228 MASSMAIL.VCU.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 14 100458 LISTES.ULAVAL.CA (Linux 3.10.0) 15 98535 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 16 95770 LISTS.ROCHESTER.EDU (Windows Server 2012 R2 Standard x64 Edition) 17 95465 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 18 95418 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 19 94717 LISTSERV.AAP.ORG (Windows Server 2012 R2 Standard x64 Edition) 20 93580 LISTSERV.BUFFALO.EDU (Linux 3.10.0)
Pos Subscribers Site --- ----------- ---- 1 5471642 LISTES.ULAVAL.CA (Linux 3.10.0) 2 4952183 LISTS.PSU.EDU (Linux 3.10.0) 3 1777535 LISTSERV.TAU.AC.IL (Linux 2.6.9) 4 1569586 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 5 1268028 LISTS.WAYNE.EDU (Linux 2.6.32) 6 1254071 LISTSERV.TAMU.EDU (Linux 3.0.101) 7 1171263 LISTSERV.UTORONTO.CA (Linux 3.10.0) 8 1059036 LISTS.UFL.EDU (Linux 2.6.32) 9 1034355 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 10 976271 LISTSERV.UA.EDU (Linux 4.12.14) 11 934912 LISTS.UMN.EDU (Linux 3.10.0) 12 853488 LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 13 833206 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 14 806338 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 15 801667 LISTSERV.ECU.EDU (Windows Server 2016 Standard x64 Edition) 16 790237 LISTSERV.UH.EDU (Linux 3.10.0) 17 752201 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 18 709597 LIST.MSU.EDU (Linux 3.10.0) 19 686565 LISTSERV.LIV.AC.UK (Linux 3.10.0) 20 676184 LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition)
Pos Lists Site --- ----- ---- 1 34077 LISTES.ULAVAL.CA (Linux 3.10.0) 2 17187 LISTS.PSU.EDU (Linux 3.10.0) 3 14174 LISTSERV.TAU.AC.IL (Linux 2.6.9) 4 9788 LISTS.CLEMSON.EDU (Linux 2.6.18) 5 9599 LISTS.UFL.EDU (Linux 2.6.32) 6 8079 LISTSERV.TECHNION.AC.IL (Linux 2.6.32) 7 7622 LISTSERV.LIV.AC.UK (Linux 3.10.0) 8 6748 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 9 5959 LISTSERV.UTORONTO.CA (Linux 3.10.0) 10 4999 LISTSERV.TAMU.EDU (Linux 3.0.101) 11 4985 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 12 4879 LISTS.UMN.EDU (Linux 3.10.0) 13 4325 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 14 4161 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 15 3803 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 16 3716 LISTS.QUEENSU.CA (Linux 3.10.0) 17 3591 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 18 3380 LIST.UVM.EDU (Linux 2.6.32) 19 3355 LISTSERV.BROWN.EDU (Linux 3.10.0) 20 2746 LISTSERV.KENT.EDU (Windows Server 2012 R2 Standard x64 Edition)
Pos Recipients Site --- ---------- ---- 1 628525 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 240181 LISTS.PSU.EDU (Linux 3.10.0) 3 237624 LISTSERV.LIV.AC.UK (Linux 3.10.0) 4 168597 LISTSERV.TAMU.EDU (Linux 3.0.101) 5 152456 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.25.1.el7.x86_64) 6 125266 LISTS.UFL.EDU (Linux 2.6.32) 7 123259 LISTS.HAWAII.EDU (Linux 3.10.0-1160.31.1.el7.x86_64) 8 115495 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 9 113638 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 10 104764 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 11 100234 LISTES.ULAVAL.CA (Linux 3.10.0) 12 95679 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 13 94350 LISTSERV.AAP.ORG (Windows Server 2012 R2 Standard x64 Edition) 14 93166 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 15 93107 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 16 89329 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 17 88891 LISTSERV.ICORS.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 18 81040 LISTSERV.UA.EDU (Linux 4.12.14) 19 80922 L.GOP.COM (Windows Server 2016 Standard x64 Edition) 20 76571 LIST.MSU.EDU (Linux 3.10.0)
Pos Subscribers Site --- ----------- ---- 1 59211 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 2 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 3 47375 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition) 4 41812 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 5 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 6 33992 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 7 33543 L-SMEAL-REPORT@LISTS.PSU.EDU (Linux 3.10.0) 8 31621 TAU-STU-ACADEMICSEC-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 9 30835 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.32) 10 28887 TAU-INNOVTL-ALL-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 11 28365 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 12 28288 L-THON-NEWS@LISTS.PSU.EDU (Linux 3.10.0) 13 27707 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 14 27479 TAU4U@LISTSERV.TAU.AC.IL (Linux 2.6.9) 15 27382 VOLUPDATE@LISTSERV.UTK.EDU (Linux 3.10.0) 16 27348 UTENNSRP@LISTSERV.UTK.EDU (Linux 3.10.0) 17 26421 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 18 24992 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0) 19 24288 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 23331 ECF-MIWD@NYED.USCOURTS.GOV (Linux 3.10.0)