![[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 780538 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 379267 LISTSERV.LIV.AC.UK (Linux 3.10.0) 3 363511 LISTS.PSU.EDU (Linux 3.10.0) 4 267124 LISTES.ULAVAL.CA (Linux 3.10.0) 5 230271 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.59.1.el7.x86_64) 6 215635 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 7 202934 LISTSERV.ACM.ORG (Windows Server 2016 Datacenter x64 Edition) 8 197382 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 9 178908 LISTS.HAWAII.EDU (Linux 3.10.0-1160.76.1.el7.x86_64) 10 177975 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 11 176477 LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition) 12 166736 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 13 158708 LISTS.UFL.EDU (Linux 2.6.32) 14 151221 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 15 147608 LISTSERV.TDBANK.CA (Windows Server 2016 Datacenter x64 Edition) 16 135166 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 17 129902 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 18 115815 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 19 113742 NASLISTS.NORIDIAN.COM (Windows Server 2019 Standard x64 Edition) 20 110894 LISTSERV.WUSTL.EDU (Windows Server 2016 Standard x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 5251966 LISTS.PSU.EDU (Linux 3.10.0) 2 5000408 LISTES.ULAVAL.CA (Linux 3.10.0) 3 1943235 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 4 1777535 LISTSERV.TAU.AC.IL (Linux 2.6.9) 5 1613852 LISTSERV.UTORONTO.CA (Linux 3.10.0) 6 1252000 LISTSERV.UA.EDU (Linux 4.12.14) 7 1108174 LISTSERV.TAMU.EDU (Linux 3.0.101) 8 1102510 LISTS.WAYNE.EDU (Linux 2.6.32) 9 1078709 LISTSERV.UH.EDU (Linux 3.10.0) 10 1065720 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 11 1059036 LISTS.UFL.EDU (Linux 2.6.32) 12 947826 LIST.MSU.EDU (Linux 3.10.0) 13 934201 LISTS.UMN.EDU (Linux 3.10.0) 14 907652 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 15 853488 LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 847431 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 17 780902 LISTSERV.ECU.EDU (Windows Server 2016 Standard x64 Edition) 18 740052 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 19 723834 LISTSERV.LIV.AC.UK (Linux 3.10.0) 20 704944 LISTS.QUEENSU.CA (Linux 3.10.0)
Pos Lists Site --- ----- ---- 1 28441 LISTES.ULAVAL.CA (Linux 3.10.0) 2 16793 LISTS.PSU.EDU (Linux 3.10.0) 3 14174 LISTSERV.TAU.AC.IL (Linux 2.6.9) 4 10884 LISTSERV.UH.EDU (Linux 3.10.0) 5 9788 LISTS.CLEMSON.EDU (Linux 2.6.18) 6 9599 LISTS.UFL.EDU (Linux 2.6.32) 7 8079 LISTSERV.TECHNION.AC.IL (Linux 2.6.32) 8 7217 LISTSERV.LIV.AC.UK (Linux 3.10.0) 9 6788 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 10 6490 LISTSERV.UTORONTO.CA (Linux 3.10.0) 11 5454 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 12 4973 LISTSERV.TAMU.EDU (Linux 3.0.101) 13 4832 LISTS.UMN.EDU (Linux 3.10.0) 14 4519 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 15 4374 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 16 3911 LISTS.QUEENSU.CA (Linux 3.10.0) 17 3830 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 18 3554 LIST.UVM.EDU (Linux 2.6.32) 19 3542 LISTSERV.BROWN.EDU (Linux 3.10.0) 20 3334 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition)
Pos Recipients Site --- ---------- ---- 1 746568 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 370751 LISTSERV.LIV.AC.UK (Linux 3.10.0) 3 360251 LISTS.PSU.EDU (Linux 3.10.0) 4 267012 LISTES.ULAVAL.CA (Linux 3.10.0) 5 230039 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.59.1.el7.x86_64) 6 191934 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 7 178543 LISTS.HAWAII.EDU (Linux 3.10.0-1160.76.1.el7.x86_64) 8 177724 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 9 176207 LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition) 10 163579 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 11 157443 LISTS.UFL.EDU (Linux 2.6.32) 12 156006 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 13 149175 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 14 130940 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 15 127726 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 16 115523 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 17 110087 LISTSERV.UTORONTO.CA (Linux 3.10.0) 18 107621 LISTSERV.AAP.ORG (Windows Server 2012 R2 Standard x64 Edition) 19 107496 LISTSERV.KENT.EDU (Windows Server 2012 R2 Standard x64 Edition) 20 99081 LIST.MSU.EDU (Linux 3.10.0)
Pos Subscribers Site --- ----------- ---- 1 42828 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition) 2 41827 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 3 40481 SUCCESS@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 4 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 5 33091 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 6 31621 TAU-STU-ACADEMICSEC-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 7 30181 UG2021FALL@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 8 29105 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 9 28887 TAU-INNOVTL-ALL-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 10 28259 L-THON-NEWS@LISTS.PSU.EDU (Linux 3.10.0) 11 27705 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 12 27479 TAU4U@LISTSERV.TAU.AC.IL (Linux 2.6.9) 13 27374 VOLUPDATE@LISTSERV.UTK.EDU (Linux 3.10.0) 14 27347 UTENNSRP@LISTSERV.UTK.EDU (Linux 3.10.0) 15 26421 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 16 25619 ECF-MIWD@NYED.USCOURTS.GOV (Linux 3.10.0) 17 24992 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0) 18 24288 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 19 23347 DSSAT@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 20 22769 STUDENT-TRAVEL-SURVEY-L@LISTSERV.OKSTATE.EDU (Windows Server 2012 Datacenter x64 Edition)