![[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 777829 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 706449 LISTSERV.TAMU.EDU (Linux 3.0.101) 3 419588 LISTS.PSU.EDU (Linux 3.10.0) 4 332157 LISTSERV.LIV.AC.UK (Linux 3.10.0) 5 281878 LISTES.ULAVAL.CA (Linux 3.10.0) 6 242217 LIST.UNM.EDU (Linux 3.10.0-1160.36.2.el7.x86_64) 7 240550 LISTS.HAWAII.EDU (Linux 3.10.0-1160.42.2.el7.x86_64) 8 226940 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 9 211704 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 10 192398 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 11 191900 LISTS.UFL.EDU (Linux 2.6.32) 12 179374 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 13 176653 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 14 169883 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 15 169048 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 16 166426 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 17 162224 LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition) 18 153147 LISTSERV.REDIRIS.ES (Linux 3.10.0-1062.9.1.el7.x86_64) 19 142751 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.31.1.el7.x86_64) 20 142423 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 5141934 LISTS.PSU.EDU (Linux 3.10.0) 2 4601384 LISTES.ULAVAL.CA (Linux 3.10.0) 3 1777535 LISTSERV.TAU.AC.IL (Linux 2.6.9) 4 1649118 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 5 1343093 LISTSERV.UTORONTO.CA (Linux 3.10.0) 6 1245713 LISTSERV.TAMU.EDU (Linux 3.0.101) 7 1059036 LISTS.UFL.EDU (Linux 2.6.32) 8 1054900 LISTS.WAYNE.EDU (Linux 2.6.32) 9 1038295 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 10 1015951 LISTSERV.UA.EDU (Linux 4.12.14) 11 927690 LISTS.UMN.EDU (Linux 3.10.0) 12 873793 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 13 871774 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 14 854389 LIST.MSU.EDU (Linux 3.10.0) 15 853488 LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 845788 LISTSERV.ECU.EDU (Windows Server 2016 Standard x64 Edition) 17 843644 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 18 829037 LISTSERV.UH.EDU (Linux 3.10.0) 19 680285 LISTSERV.LIV.AC.UK (Linux 3.10.0) 20 669734 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition)
Pos Lists Site --- ----- ---- 1 27860 LISTES.ULAVAL.CA (Linux 3.10.0) 2 16471 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 7061 LISTSERV.LIV.AC.UK (Linux 3.10.0) 8 6759 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 9 6050 LISTSERV.UTORONTO.CA (Linux 3.10.0) 10 5104 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 11 4992 LISTSERV.TAMU.EDU (Linux 3.0.101) 12 4828 LISTS.UMN.EDU (Linux 3.10.0) 13 4375 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 14 4210 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 15 3852 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 16 3755 LISTS.QUEENSU.CA (Linux 3.10.0) 17 3440 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 18 3394 LISTSERV.BROWN.EDU (Linux 3.10.0) 19 3372 LIST.UVM.EDU (Linux 2.6.32) 20 2779 LISTSERV.KENT.EDU (Windows Server 2012 R2 Standard x64 Edition)
Pos Recipients Site --- ---------- ---- 1 746869 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 698015 LISTSERV.TAMU.EDU (Linux 3.0.101) 3 416499 LISTS.PSU.EDU (Linux 3.10.0) 4 324977 LISTSERV.LIV.AC.UK (Linux 3.10.0) 5 281723 LISTES.ULAVAL.CA (Linux 3.10.0) 6 242061 LIST.UNM.EDU (Linux 3.10.0-1160.36.2.el7.x86_64) 7 239880 LISTS.HAWAII.EDU (Linux 3.10.0-1160.42.2.el7.x86_64) 8 223355 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 9 190261 LISTS.UFL.EDU (Linux 2.6.32) 10 176866 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 11 176266 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 12 166819 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 13 166182 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 14 164976 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 15 161995 LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition) 16 159834 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 17 150908 LISTSERV.REDIRIS.ES (Linux 3.10.0-1062.9.1.el7.x86_64) 18 142593 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.31.1.el7.x86_64) 19 140169 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 20 117140 LISTSERV.UTORONTO.CA (Linux 3.10.0)
Pos Subscribers Site --- ----------- ---- 1 59191 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 2 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 3 41929 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition) 4 41813 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 5 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 6 33983 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 7 31621 TAU-STU-ACADEMICSEC-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 8 28887 TAU-INNOVTL-ALL-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 9 28667 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 10 28283 L-THON-NEWS@LISTS.PSU.EDU (Linux 3.10.0) 11 27707 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 12 27479 TAU4U@LISTSERV.TAU.AC.IL (Linux 2.6.9) 13 27381 VOLUPDATE@LISTSERV.UTK.EDU (Linux 3.10.0) 14 27348 UTENNSRP@LISTSERV.UTK.EDU (Linux 3.10.0) 15 26421 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 16 24992 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0) 17 24556 ECF-MIWD@NYED.USCOURTS.GOV (Linux 3.10.0) 18 24288 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 19 22770 STUDENT-TRAVEL-SURVEY-L@LISTSERV.OKSTATE.EDU (Windows Server 2012 Datacenter x64 Edition) 20 21994 PRESIDENT-WELCOME@LISTSERV.TAU.AC.IL (Linux 2.6.9)