![[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 785851 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 714035 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 3 323420 LISTS.PSU.EDU (AIX 6.1) 4 261361 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-957.12.2.el7.x86_64) 5 212162 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 6 204623 LISTSERV.LIV.AC.UK (Linux 2.6.32) 7 202185 LIST.UNM.EDU (Linux 2.6.32-754.29.2.el6.x86_64) 8 181824 LISTS.HAWAII.EDU (Linux 2.6.32-754.29.1.el6.x86_64) 9 170680 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 10 166554 LISTSERV.TAMU.EDU (Linux 3.0.101) 11 164139 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 12 158462 LISTES.ULAVAL.CA (Linux 3.10.0) 13 156019 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 14 154031 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 15 151857 LISTSERV.AAP.ORG (Windows Server 2012 R2 Standard x64 Edition) 16 151688 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 17 142149 LISTS.UFL.EDU (Linux 2.6.32) 18 140125 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 19 139054 LISTSERV.UGA.EDU (Linux 2.6.32) 20 138847 LISTSERV.UA.EDU (Linux 4.12.14)
Pos Subscribers Site --- ----------- ---- 1 4847976 LISTS.PSU.EDU (AIX 6.1) 2 4196017 LISTES.ULAVAL.CA (Linux 3.10.0) 3 2331039 LS.KULEUVEN.BE (Linux 2.6.32) 4 1634873 LISTSERV.UGA.EDU (Linux 2.6.32) 5 1454909 LISTSERV.TAU.AC.IL (Linux 2.6.9) 6 1225007 LISTS.WAYNE.EDU (Linux 2.6.32) 7 1198595 LISTSERV.UTORONTO.CA (Linux 3.10.0) 8 1188521 LISTSERV.TAMU.EDU (Linux 3.0.101) 9 1081695 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 10 1059036 LISTS.UFL.EDU (Linux 2.6.32) 11 1022108 LIST.MSU.EDU (Linux 3.10.0) 12 967520 LISTS.UMN.EDU (Linux 3.10.0) 13 871565 LISTSERV.ECU.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 14 845260 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 15 843046 LISTSERV.UA.EDU (Linux 4.12.14) 16 841040 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 17 810707 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 18 746767 LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 19 739463 LISTSERV.UH.EDU (Linux 3.10.0) 20 699338 LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
Pos Lists Site --- ----- ---- 1 27546 LISTES.ULAVAL.CA (Linux 3.10.0) 2 16569 LISTS.PSU.EDU (AIX 6.1) 3 13895 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 7445 LISTSERV.LIV.AC.UK (Linux 2.6.32) 8 6719 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 9 6250 LISTSERV.UGA.EDU (Linux 2.6.32) 10 5656 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 11 5271 LISTSERV.UTORONTO.CA (Linux 3.10.0) 12 5091 LS.KULEUVEN.BE (Linux 2.6.32) 13 5031 LISTSERV.TAMU.EDU (Linux 3.0.101) 14 4869 LISTS.UMN.EDU (Linux 3.10.0) 15 4192 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 16 4127 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 17 4068 LISTS.QUEENSU.CA (Linux 3.10.0) 18 4012 LISTSERV.MILLERSVILLE.EDU (Linux 2.6.32) 19 3647 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 20 3296 LIST.UVM.EDU (Linux 2.6.32)
Pos Recipients Site --- ---------- ---- 1 756643 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 712993 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 3 319230 LISTS.PSU.EDU (AIX 6.1) 4 261147 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-957.12.2.el7.x86_64) 5 201976 LIST.UNM.EDU (Linux 2.6.32-754.29.2.el6.x86_64) 6 197298 LISTSERV.LIV.AC.UK (Linux 2.6.32) 7 179161 LISTS.HAWAII.EDU (Linux 2.6.32-754.29.1.el6.x86_64) 8 168296 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 9 165943 LISTSERV.TAMU.EDU (Linux 3.0.101) 10 158256 LISTES.ULAVAL.CA (Linux 3.10.0) 11 153586 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 12 151447 LISTSERV.AAP.ORG (Windows Server 2012 R2 Standard x64 Edition) 13 150597 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 14 150043 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 15 140617 LISTS.UFL.EDU (Linux 2.6.32) 16 135388 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 17 135362 LISTSERV.UGA.EDU (Linux 2.6.32) 18 134401 LISTSERV.UA.EDU (Linux 4.12.14) 19 134252 LISTSERV.ICORS.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 20 128488 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 59356 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 2 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 3 52531 ECF-EDNY@NYED.USCOURTS.GOV (Linux 3.10.0) 4 41796 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 5 40811 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 6 36455 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 7 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 8 33596 L-SMEAL-REPORT@LISTS.PSU.EDU (AIX 6.1) 9 30835 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.32) 10 28918 BEDRIJVENLIJST@LS.KULEUVEN.BE (Linux 2.6.32) 11 28918 BEDRIJVENLIJST2@LS.KULEUVEN.BE (Linux 2.6.32) 12 28309 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 13 27921 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32) 14 27709 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 15 27398 VOLUPDATE@LISTSERV.UTK.EDU (Solaris 2.10) 16 26419 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 17 25522 ISMA@LS.KULEUVEN.BE (Linux 2.6.32) 18 25009 2019-STEM-EVENT-L@LISTSERV.OKSTATE.EDU (Windows Server 2012 Datacenter x64 Edition) 19 24992 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0) 20 24350 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition)