![[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 694875 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 617039 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 3 526130 LISTSERV.TAMU.EDU (Linux 3.0.101) 4 431968 LISTS.PSU.EDU (Linux 3.10.0) 5 418479 LISTSERV.LIV.AC.UK (Linux 3.10.0) 6 307377 LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition) 7 284462 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 8 244828 LISTES.ULAVAL.CA (Linux 3.10.0) 9 241868 LISTS.UFL.EDU (Linux 2.6.32) 10 233952 LISTSERV.UGA.EDU (Linux 2.6.32) 11 224774 LISTS.HAWAII.EDU (Linux 2.6.32-754.36.1.el6.x86_64) 12 203033 LISTSERV.TDBANK.CA (Windows Server 2012 R2 Datacenter x64 Edition) 13 200416 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 14 198385 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 15 190801 LISTS.APA.ORG (Windows Server 2016 Datacenter x64 Edition) 16 172814 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 17 169656 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 18 165416 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 19 160588 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 20 158185 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 5090048 LISTES.ULAVAL.CA (Linux 3.10.0) 2 4976585 LISTS.PSU.EDU (Linux 3.10.0) 3 2299124 LS.KULEUVEN.BE (Linux 2.6.32) 4 1750920 LISTSERV.TAU.AC.IL (Linux 2.6.9) 5 1506524 LISTSERV.UGA.EDU (Linux 2.6.32) 6 1298127 LISTS.WAYNE.EDU (Linux 2.6.32) 7 1269558 LISTSERV.UTORONTO.CA (Linux 3.10.0) 8 1220410 LISTSERV.TAMU.EDU (Linux 3.0.101) 9 1157570 LISTSERV.UA.EDU (Linux 4.12.14) 10 1135640 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 11 1124929 LIST.MSU.EDU (Linux 3.10.0) 12 1059036 LISTS.UFL.EDU (Linux 2.6.32) 13 946792 LISTS.UMN.EDU (Linux 3.10.0) 14 884237 LISTSERV.ECU.EDU (Windows Server 2016 Standard x64 Edition) 15 865429 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 837000 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 17 833894 LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 18 833294 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 19 786419 LISTSERV.UH.EDU (Linux 3.10.0) 20 689998 LISTSERV.LIV.AC.UK (Linux 3.10.0)
Pos Lists Site --- ----- ---- 1 30536 LISTES.ULAVAL.CA (Linux 3.10.0) 2 17022 LISTS.PSU.EDU (Linux 3.10.0) 3 14066 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 7566 LISTSERV.LIV.AC.UK (Linux 3.10.0) 8 6739 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 9 5812 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 10 5775 LISTSERV.UTORONTO.CA (Linux 3.10.0) 11 5347 LS.KULEUVEN.BE (Linux 2.6.32) 12 5015 LISTSERV.TAMU.EDU (Linux 3.0.101) 13 4939 LISTSERV.UGA.EDU (Linux 2.6.32) 14 4872 LISTS.UMN.EDU (Linux 3.10.0) 15 4273 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 4208 LISTS.QUEENSU.CA (Linux 3.10.0) 17 3781 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 18 3656 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 19 3365 LIST.UVM.EDU (Linux 2.6.32) 20 3343 LISTSERV.BROWN.EDU (Linux 3.10.0)
Pos Recipients Site --- ---------- ---- 1 665694 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 616344 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 3 520825 LISTSERV.TAMU.EDU (Linux 3.0.101) 4 428786 LISTS.PSU.EDU (Linux 3.10.0) 5 409798 LISTSERV.LIV.AC.UK (Linux 3.10.0) 6 307025 LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition) 7 244479 LISTES.ULAVAL.CA (Linux 3.10.0) 8 240250 LISTS.UFL.EDU (Linux 2.6.32) 9 229646 LISTSERV.UGA.EDU (Linux 2.6.32) 10 223193 LISTS.HAWAII.EDU (Linux 2.6.32-754.36.1.el6.x86_64) 11 195791 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 12 187762 LISTS.APA.ORG (Windows Server 2016 Datacenter x64 Edition) 13 179309 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 14 170827 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 15 169385 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 16 165232 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 17 155695 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 18 155489 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 19 146887 LISTSERV.UTORONTO.CA (Linux 3.10.0) 20 139477 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64)
Pos Subscribers Site --- ----------- ---- 1 59235 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 2 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 3 43408 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition) 4 41810 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 5 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 6 34000 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 7 33576 L-SMEAL-REPORT@LISTS.PSU.EDU (Linux 3.10.0) 8 32997 TAU-STU-ACADEMICSEC-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 9 30835 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.32) 10 29647 TAU-INNOVTL-ALL-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 11 28918 BEDRIJVENLIJST@LS.KULEUVEN.BE (Linux 2.6.32) 12 28918 BEDRIJVENLIJST2@LS.KULEUVEN.BE (Linux 2.6.32) 13 28302 L-THON-NEWS@LISTS.PSU.EDU (Linux 3.10.0) 14 27707 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 15 27480 TAU4U@LISTSERV.TAU.AC.IL (Linux 2.6.9) 16 27390 VOLUPDATE@LISTSERV.UTK.EDU (Linux 3.10.0) 17 26924 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32) 18 26419 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 19 25580 ISMA@LS.KULEUVEN.BE (Linux 2.6.32) 20 24992 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0)