![[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 712416 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 378763 LISTSERV.LIV.AC.UK (Linux 3.10.0) 3 337308 LISTS.PSU.EDU (Linux 3.10.0) 4 278678 LISTES.ULAVAL.CA (Linux 3.10.0) 5 244565 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 6 209276 LISTSERV.ACM.ORG (Windows Server 2016 Datacenter x64 Edition) 7 183873 LISTS.HAWAII.EDU (Linux 3.10.0-1160.81.1.el7.x86_64) 8 182071 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 9 165726 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 10 160775 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 11 152635 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 12 146626 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 13 146602 LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition) 14 143374 LISTS.UFL.EDU (Linux 2.6.32) 15 130897 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 16 115370 LISTSERV.UTORONTO.CA (Linux 3.10.0) 17 107000 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.59.1.el7.x86_64) 18 106246 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 19 103101 LISTSERV.ICORS.ORG (Windows Server 2016 Datacenter x64 Edition) 20 93871 LISTS.ROCHESTER.EDU (Windows Server 2012 R2 Standard x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 5499315 LISTS.PSU.EDU (Linux 3.10.0) 2 4990374 LISTES.ULAVAL.CA (Linux 3.10.0) 3 1959534 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 4 1777535 LISTSERV.TAU.AC.IL (Linux 2.6.9) 5 1641865 LISTSERV.UTORONTO.CA (Linux 3.10.0) 6 1136947 LISTSERV.TAMU.EDU (Linux 3.0.101) 7 1102623 LISTSERV.UA.EDU (Linux 4.12.14) 8 1064378 LISTS.WAYNE.EDU (Linux 2.6.32) 9 1059444 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 10 1059036 LISTS.UFL.EDU (Linux 2.6.32) 11 968071 LIST.MSU.EDU (Linux 3.10.0) 12 925987 LISTS.UMN.EDU (Linux 3.10.0) 13 901485 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 14 882619 LISTSERV.UH.EDU (Linux 3.10.0) 15 853488 LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 838262 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 17 780497 LISTSERV.ECU.EDU (Windows Server 2016 Standard x64 Edition) 18 709122 LISTS.QUEENSU.CA (Linux 3.10.0) 19 708043 LISTSERV.LIV.AC.UK (Linux 3.10.0) 20 664641 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition)
Pos Lists Site --- ----- ---- 1 28469 LISTES.ULAVAL.CA (Linux 3.10.0) 2 16807 LISTS.PSU.EDU (Linux 3.10.0) 3 14174 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 7224 LISTSERV.LIV.AC.UK (Linux 3.10.0) 8 6793 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 9 6557 LISTSERV.UTORONTO.CA (Linux 3.10.0) 10 5517 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 11 4972 LISTSERV.TAMU.EDU (Linux 3.0.101) 12 4846 LISTS.UMN.EDU (Linux 3.10.0) 13 4540 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 14 4388 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 15 3920 LISTS.QUEENSU.CA (Linux 3.10.0) 16 3603 LIST.UVM.EDU (Linux 2.6.32) 17 3560 LISTSERV.BROWN.EDU (Linux 3.10.0) 18 3343 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 19 2821 LISTSERV.KENT.EDU (Windows Server 2012 R2 Standard x64 Edition) 20 2773 LISTS.WAYNE.EDU (Linux 2.6.32)
Pos Recipients Site --- ---------- ---- 1 683132 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 370158 LISTSERV.LIV.AC.UK (Linux 3.10.0) 3 334479 LISTS.PSU.EDU (Linux 3.10.0) 4 278505 LISTES.ULAVAL.CA (Linux 3.10.0) 5 244183 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 6 178947 LISTS.HAWAII.EDU (Linux 3.10.0-1160.81.1.el7.x86_64) 7 177186 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 8 165573 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 9 149797 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 10 146329 LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition) 11 143905 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 12 142144 LISTS.UFL.EDU (Linux 2.6.32) 13 128759 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 14 128277 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 15 115445 LISTSERV.UTORONTO.CA (Linux 3.10.0) 16 106901 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.59.1.el7.x86_64) 17 102190 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 18 101628 LISTSERV.ICORS.ORG (Windows Server 2016 Datacenter x64 Edition) 19 90175 LIST.UVM.EDU (Linux 2.6.32) 20 85539 LISTSERV.KENT.EDU (Windows Server 2012 R2 Standard x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 43021 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition) 2 41831 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 3 40479 SUCCESS@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 4 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 5 31621 TAU-STU-ACADEMICSEC-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 6 30179 UG2021FALL@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 7 29290 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 8 28887 TAU-INNOVTL-ALL-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 9 28250 L-THON-NEWS@LISTS.PSU.EDU (Linux 3.10.0) 10 27705 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 11 27479 TAU4U@LISTSERV.TAU.AC.IL (Linux 2.6.9) 12 27372 VOLUPDATE@LISTSERV.UTK.EDU (Linux 3.10.0) 13 27346 UTENNSRP@LISTSERV.UTK.EDU (Linux 3.10.0) 14 26421 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 15 25619 ECF-MIWD@NYED.USCOURTS.GOV (Linux 3.10.0) 16 24992 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0) 17 24288 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 18 23799 DSSAT@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 19 22768 STUDENT-TRAVEL-SURVEY-L@LISTSERV.OKSTATE.EDU (Windows Server 2012 Datacenter x64 Edition) 20 22363 L-AGSCINEWS@LISTS.PSU.EDU (Linux 3.10.0)