![[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 1076656 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 2 888376 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 3 418878 LISTSERV.LIV.AC.UK (Linux 3.10.0) 4 388432 LISTS.PSU.EDU (Linux 3.10.0) 5 287395 LISTES.ULAVAL.CA (Linux 3.10.0) 6 284062 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 7 244598 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.42.2.el7.x86_64) 8 210209 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 9 205627 LISTS.HAWAII.EDU (Linux 3.10.0-1160.45.1.el7.x86_64) 10 193507 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 11 187481 LISTSERV.REDIRIS.ES (Linux 3.10.0-1062.9.1.el7.x86_64) 12 186480 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 13 181403 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 14 168311 LISTS.UFL.EDU (Linux 2.6.32) 15 155170 LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition) 16 141903 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 17 141705 LISTSERV.UTORONTO.CA (Linux 3.10.0) 18 141477 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 19 120809 LISTS.ROCHESTER.EDU (Windows Server 2012 R2 Standard x64 Edition) 20 109576 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 5080839 LISTS.PSU.EDU (Linux 3.10.0) 2 4650505 LISTES.ULAVAL.CA (Linux 3.10.0) 3 1777535 LISTSERV.TAU.AC.IL (Linux 2.6.9) 4 1732790 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 5 1502957 LISTSERV.UTORONTO.CA (Linux 3.10.0) 6 1244951 LISTSERV.TAMU.EDU (Linux 3.0.101) 7 1073364 LISTS.WAYNE.EDU (Linux 2.6.32) 8 1059036 LISTS.UFL.EDU (Linux 2.6.32) 9 1044264 LISTSERV.UA.EDU (Linux 4.12.14) 10 1036018 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 11 1035028 LIST.MSU.EDU (Linux 3.10.0) 12 931581 LISTS.UMN.EDU (Linux 3.10.0) 13 879394 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 14 864662 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 15 853488 LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 844771 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 17 840809 LISTSERV.UH.EDU (Linux 3.10.0) 18 806520 LISTSERV.ECU.EDU (Windows Server 2016 Standard x64 Edition) 19 693420 LISTSERV.LIV.AC.UK (Linux 3.10.0) 20 679167 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition)
Pos Lists Site --- ----- ---- 1 27937 LISTES.ULAVAL.CA (Linux 3.10.0) 2 16531 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 7115 LISTSERV.LIV.AC.UK (Linux 3.10.0) 8 6763 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 9 6126 LISTSERV.UTORONTO.CA (Linux 3.10.0) 10 5159 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 11 4987 LISTSERV.TAMU.EDU (Linux 3.0.101) 12 4813 LISTS.UMN.EDU (Linux 3.10.0) 13 4404 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 14 4231 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 15 3799 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 16 3748 LISTS.QUEENSU.CA (Linux 3.10.0) 17 3414 LISTSERV.BROWN.EDU (Linux 3.10.0) 18 3393 LIST.UVM.EDU (Linux 2.6.32) 19 3283 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 20 2772 LISTSERV.KENT.EDU (Windows Server 2012 R2 Standard x64 Edition)
Pos Recipients Site --- ---------- ---- 1 1074907 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 2 855228 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 3 411037 LISTSERV.LIV.AC.UK (Linux 3.10.0) 4 385049 LISTS.PSU.EDU (Linux 3.10.0) 5 287177 LISTES.ULAVAL.CA (Linux 3.10.0) 6 244382 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.42.2.el7.x86_64) 7 205933 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 8 203413 LISTS.HAWAII.EDU (Linux 3.10.0-1160.45.1.el7.x86_64) 9 190070 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 10 185197 LISTSERV.REDIRIS.ES (Linux 3.10.0-1062.9.1.el7.x86_64) 11 181168 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 12 166449 LISTS.UFL.EDU (Linux 2.6.32) 13 154956 LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition) 14 141510 LISTSERV.UTORONTO.CA (Linux 3.10.0) 15 139320 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 16 138409 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 17 137293 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 18 107299 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 19 99768 LISTSERV.ICORS.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 20 98328 LISTSERV.UA.EDU (Linux 4.12.14)
Pos Subscribers Site --- ----------- ---- 1 59182 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 2 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 3 42431 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition) 4 41816 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 5 39354 SUCCESS@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 6 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 7 33848 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 8 31621 TAU-STU-ACADEMICSEC-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 9 30228 UG2021FALL@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 10 28887 TAU-INNOVTL-ALL-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 11 28755 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 12 28279 L-THON-NEWS@LISTS.PSU.EDU (Linux 3.10.0) 13 27706 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 14 27479 TAU4U@LISTSERV.TAU.AC.IL (Linux 2.6.9) 15 27381 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 24633 ECF-MIWD@NYED.USCOURTS.GOV (Linux 3.10.0) 20 24288 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition)