![[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 810667 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 515730 LISTSERV.TAMU.EDU (Linux 3.0.101) 3 429821 LISTS.PSU.EDU (AIX 6.1) 4 409780 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 5 299477 LISTSERV.LIV.AC.UK (Linux 2.6.32) 6 258096 LISTES.ULAVAL.CA (Linux 3.10.0) 7 253478 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 8 240466 LISTSERV.UGA.EDU (Linux 2.6.32) 9 224592 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 10 207385 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 11 206437 LISTS.HAWAII.EDU (Linux 2.6.32-754.35.1.el6.x86_64) 12 206308 LISTS.UFL.EDU (Linux 2.6.32) 13 198945 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1127.18.2.el7.x86_64) 14 198554 LIST.UNM.EDU (Linux 2.6.32-754.30.2.el6.x86_64) 15 197491 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 16 188367 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 17 186680 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 18 179855 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 19 169312 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 20 155600 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 5188324 LISTES.ULAVAL.CA (Linux 3.10.0) 2 4847976 LISTS.PSU.EDU (AIX 6.1) 3 2212283 LS.KULEUVEN.BE (Linux 2.6.32) 4 1520280 LISTSERV.TAU.AC.IL (Linux 2.6.9) 5 1400835 LISTSERV.UGA.EDU (Linux 2.6.32) 6 1323690 LISTS.WAYNE.EDU (Linux 2.6.32) 7 1217494 LISTSERV.UTORONTO.CA (Linux 3.10.0) 8 1193329 LISTSERV.TAMU.EDU (Linux 3.0.101) 9 1136183 LIST.MSU.EDU (Linux 3.10.0) 10 1133298 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 11 1059036 LISTS.UFL.EDU (Linux 2.6.32) 12 962070 LISTS.UMN.EDU (Linux 3.10.0) 13 923634 LISTSERV.UA.EDU (Linux 4.12.14) 14 921167 LISTSERV.ECU.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 15 847619 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 16 846155 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 17 842304 LISTSERV.UH.EDU (Linux 3.10.0) 18 840297 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 19 806244 LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 751436 LISTS.MAINE.EDU (Linux 3.10.0)
Pos Lists Site --- ----- ---- 1 34750 LISTES.ULAVAL.CA (Linux 3.10.0) 2 16569 LISTS.PSU.EDU (AIX 6.1) 3 11361 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 7460 LISTSERV.LIV.AC.UK (Linux 2.6.32) 8 6735 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 9 5714 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 10 5482 LISTSERV.UTORONTO.CA (Linux 3.10.0) 11 5187 LS.KULEUVEN.BE (Linux 2.6.32) 12 5024 LISTSERV.TAMU.EDU (Linux 3.0.101) 13 4911 LISTS.UMN.EDU (Linux 3.10.0) 14 4818 LISTSERV.UGA.EDU (Linux 2.6.32) 15 4213 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 4170 LISTS.QUEENSU.CA (Linux 3.10.0) 17 4133 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 18 3842 LISTSERV.MILLERSVILLE.EDU (Linux 2.6.32) 19 3729 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 20 3330 LISTSERV.BROWN.EDU (Linux 3.10.0)
Pos Recipients Site --- ---------- ---- 1 779682 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 515170 LISTSERV.TAMU.EDU (Linux 3.0.101) 3 426680 LISTS.PSU.EDU (AIX 6.1) 4 409267 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 5 290774 LISTSERV.LIV.AC.UK (Linux 2.6.32) 6 257909 LISTES.ULAVAL.CA (Linux 3.10.0) 7 235323 LISTSERV.UGA.EDU (Linux 2.6.32) 8 222245 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 9 205802 LISTS.HAWAII.EDU (Linux 2.6.32-754.35.1.el6.x86_64) 10 204418 LISTS.UFL.EDU (Linux 2.6.32) 11 202887 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 12 198743 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1127.18.2.el7.x86_64) 13 198348 LIST.UNM.EDU (Linux 2.6.32-754.30.2.el6.x86_64) 14 185920 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 15 184289 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 16 179648 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 17 174804 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 18 161467 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 19 152638 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 20 143569 L.GOP.COM (Windows Server 2016 Standard x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 59299 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 2 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 3 43010 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 4 41803 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 5 36431 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 6 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 7 33596 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 28309 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 12 27708 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 13 27478 TAU4U@LISTSERV.TAU.AC.IL (Linux 2.6.9) 14 27442 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32) 15 27390 VOLUPDATE@LISTSERV.UTK.EDU (Solaris 2.10) 16 26418 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 17 25574 ISMA@LS.KULEUVEN.BE (Linux 2.6.32) 18 24992 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0) 19 24322 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 23332 ECF-MIWD@NYED.USCOURTS.GOV (Linux 3.10.0)