![[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 800465 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 469973 LISTSERV.TAMU.EDU (Linux 3.0.101) 3 357697 LISTSERV.LIV.AC.UK (Linux 2.6.32) 4 313260 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 5 297621 LISTS.PSU.EDU (AIX 6.1) 6 235184 LISTES.ULAVAL.CA (Linux 3.10.0) 7 216951 LISTSERV.UGA.EDU (Linux 2.6.32) 8 209929 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 9 192329 LISTS.HAWAII.EDU (Linux 2.6.32-754.35.1.el6.x86_64) 10 189791 LISTS.UFL.EDU (Linux 2.6.32) 11 176395 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 12 173824 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 13 151287 LISTSERV.TDBANK.CA (Windows Server 2012 R2 Datacenter x64 Edition) 14 151200 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 15 146744 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 16 145741 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 17 138763 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 18 126250 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 19 123687 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 20 123167 MASSMAIL.VCU.EDU (Windows Server 2012 R2 Datacenter x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 5188324 LISTES.ULAVAL.CA (Linux 3.10.0) 2 4974317 LISTS.PSU.EDU (AIX 6.1) 3 2278113 LS.KULEUVEN.BE (Linux 2.6.32) 4 1594601 LISTSERV.TAU.AC.IL (Linux 2.6.9) 5 1464158 LISTSERV.UGA.EDU (Linux 2.6.32) 6 1319752 LISTS.WAYNE.EDU (Linux 2.6.32) 7 1217494 LISTSERV.UTORONTO.CA (Linux 3.10.0) 8 1194816 LISTSERV.TAMU.EDU (Linux 3.0.101) 9 1146555 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 10 1127817 LIST.MSU.EDU (Linux 3.10.0) 11 1059036 LISTS.UFL.EDU (Linux 2.6.32) 12 953995 LISTS.UMN.EDU (Linux 3.10.0) 13 938258 LISTSERV.UA.EDU (Linux 4.12.14) 14 869959 LISTSERV.ECU.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 15 837342 LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 833553 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 17 833277 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 18 821245 LISTSERV.UH.EDU (Linux 3.10.0) 19 808968 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 20 744155 LISTS.MAINE.EDU (Linux 3.10.0)
Pos Lists Site --- ----- ---- 1 34750 LISTES.ULAVAL.CA (Linux 3.10.0) 2 17021 LISTS.PSU.EDU (AIX 6.1) 3 11860 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 7527 LISTSERV.LIV.AC.UK (Linux 2.6.32) 8 6734 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 9 5792 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 10 5482 LISTSERV.UTORONTO.CA (Linux 3.10.0) 11 5294 LS.KULEUVEN.BE (Linux 2.6.32) 12 5022 LISTSERV.TAMU.EDU (Linux 3.0.101) 13 4914 LISTS.UMN.EDU (Linux 3.10.0) 14 4892 LISTSERV.UGA.EDU (Linux 2.6.32) 15 4238 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 4192 LISTS.QUEENSU.CA (Linux 3.10.0) 17 3985 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 18 3733 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 19 3337 LIST.UVM.EDU (Linux 2.6.32) 20 3324 LISTSERV.BROWN.EDU (Linux 3.10.0)
Pos Recipients Site --- ---------- ---- 1 771233 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 469285 LISTSERV.TAMU.EDU (Linux 3.0.101) 3 347326 LISTSERV.LIV.AC.UK (Linux 2.6.32) 4 312704 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 5 294402 LISTS.PSU.EDU (AIX 6.1) 6 234951 LISTES.ULAVAL.CA (Linux 3.10.0) 7 212493 LISTSERV.UGA.EDU (Linux 2.6.32) 8 190296 LISTS.HAWAII.EDU (Linux 2.6.32-754.35.1.el6.x86_64) 9 188706 LISTS.UFL.EDU (Linux 2.6.32) 10 174189 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 11 149398 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 12 146509 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 13 138558 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 14 137965 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 15 122306 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 16 121197 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 17 119228 LISTSERV.UTORONTO.CA (Linux 3.10.0) 18 119149 LISTSERV.AAP.ORG (Windows Server 2012 R2 Standard x64 Edition) 19 118300 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 117538 LISTSERV.ICORS.ORG (Windows Server 2012 R2 Datacenter x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 59274 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 2 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 3 43218 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 4 41807 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 5 35358 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 6 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 7 33580 L-SMEAL-REPORT@LISTS.PSU.EDU (AIX 6.1) 8 30835 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.32) 9 28918 BEDRIJVENLIJST@LS.KULEUVEN.BE (Linux 2.6.32) 10 28918 BEDRIJVENLIJST2@LS.KULEUVEN.BE (Linux 2.6.32) 11 28304 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 12 27708 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 13 27480 TAU4U@LISTSERV.TAU.AC.IL (Linux 2.6.9) 14 27390 VOLUPDATE@LISTSERV.UTK.EDU (Solaris 2.10) 15 27196 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32) 16 26418 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 17 25576 ISMA@LS.KULEUVEN.BE (Linux 2.6.32) 18 24992 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0) 19 24312 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 23332 ECF-MIWD@NYED.USCOURTS.GOV (Linux 3.10.0)