![[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 963787 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 771532 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 3 639110 LISTSERV.TAMU.EDU (Linux 3.0.101) 4 429184 LISTS.PSU.EDU (Linux 3.10.0) 5 399973 LISTSERV.LIV.AC.UK (Linux 3.10.0) 6 271098 LISTES.ULAVAL.CA (Linux 3.10.0) 7 246126 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.11.1.el7.x86_64) 8 233271 LISTSERV.UGA.EDU (Linux 2.6.32) 9 233178 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 10 220690 LISTS.UFL.EDU (Linux 2.6.32) 11 215843 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 12 207464 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 13 198524 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 14 189784 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 15 182924 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 16 179711 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 17 176502 LISTS.HAWAII.EDU (Linux 2.6.32-754.36.1.el6.x86_64) 18 168784 LISTSERV.TDBANK.CA (Windows Server 2012 R2 Datacenter x64 Edition) 19 166887 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 20 154353 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 4848576 LISTS.PSU.EDU (Linux 3.10.0) 2 4458732 LISTES.ULAVAL.CA (Linux 3.10.0) 3 2283378 LS.KULEUVEN.BE (Linux 2.6.32) 4 1629052 LISTSERV.TAU.AC.IL (Linux 2.6.9) 5 1463924 LISTSERV.UGA.EDU (Linux 2.6.32) 6 1444610 LISTSERV.UTORONTO.CA (Linux 3.10.0) 7 1298680 LISTS.WAYNE.EDU (Linux 2.6.32) 8 1193073 LISTSERV.TAMU.EDU (Linux 3.0.101) 9 1124074 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 10 1121598 LIST.MSU.EDU (Linux 3.10.0) 11 1059036 LISTS.UFL.EDU (Linux 2.6.32) 12 967327 LISTS.UMN.EDU (Linux 3.10.0) 13 964647 LISTSERV.UA.EDU (Linux 4.12.14) 14 887411 LISTSERV.ECU.EDU (Windows Server 2016 Standard x64 Edition) 15 852124 LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 849665 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 17 833299 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 18 824410 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 19 781178 LISTSERV.UH.EDU (Linux 3.10.0) 20 694846 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition)
Pos Lists Site --- ----- ---- 1 27404 LISTES.ULAVAL.CA (Linux 3.10.0) 2 17009 LISTS.PSU.EDU (Linux 3.10.0) 3 12018 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 7547 LISTSERV.LIV.AC.UK (Linux 3.10.0) 8 6736 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 9 5803 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 10 5713 LISTSERV.UTORONTO.CA (Linux 3.10.0) 11 5315 LS.KULEUVEN.BE (Linux 2.6.32) 12 5014 LISTSERV.TAMU.EDU (Linux 3.0.101) 13 4921 LISTSERV.UGA.EDU (Linux 2.6.32) 14 4913 LISTS.UMN.EDU (Linux 3.10.0) 15 4243 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 4183 LISTS.QUEENSU.CA (Linux 3.10.0) 17 3904 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 18 3753 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 19 3355 LIST.UVM.EDU (Linux 2.6.32) 20 3329 LISTSERV.BROWN.EDU (Linux 3.10.0)
Pos Recipients Site --- ---------- ---- 1 931209 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 769913 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 3 638080 LISTSERV.TAMU.EDU (Linux 3.0.101) 4 425420 LISTS.PSU.EDU (Linux 3.10.0) 5 388193 LISTSERV.LIV.AC.UK (Linux 3.10.0) 6 270561 LISTES.ULAVAL.CA (Linux 3.10.0) 7 245903 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.11.1.el7.x86_64) 8 228704 LISTSERV.UGA.EDU (Linux 2.6.32) 9 218813 LISTS.UFL.EDU (Linux 2.6.32) 10 196298 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 11 188370 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 12 185465 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 13 182659 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 14 177243 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 15 176342 LISTS.HAWAII.EDU (Linux 2.6.32-754.36.1.el6.x86_64) 16 166678 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 17 162710 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 18 151653 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 19 145525 LISTSERV.UTORONTO.CA (Linux 3.10.0) 20 122831 LISTSERV.AAP.ORG (Windows Server 2012 R2 Standard x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 59261 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 2 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 3 43197 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition) 4 41807 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 5 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 6 34033 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 7 33579 L-SMEAL-REPORT@LISTS.PSU.EDU (Linux 3.10.0) 8 30835 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.32) 9 30003 TAU-INNOVTL-ALL-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 10 28918 BEDRIJVENLIJST@LS.KULEUVEN.BE (Linux 2.6.32) 11 28918 BEDRIJVENLIJST2@LS.KULEUVEN.BE (Linux 2.6.32) 12 28302 L-THON-NEWS@LISTS.PSU.EDU (Linux 3.10.0) 13 27708 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 14 27480 TAU4U@LISTSERV.TAU.AC.IL (Linux 2.6.9) 15 27390 VOLUPDATE@LISTSERV.UTK.EDU (Linux 3.10.0) 16 27116 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32) 17 26418 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 18 25576 ISMA@LS.KULEUVEN.BE (Linux 2.6.32) 19 24992 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0) 20 24308 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition)