![[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 807163 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 428614 LISTSERV.LIV.AC.UK (Linux 3.10.0) 3 370114 LISTS.PSU.EDU (Linux 3.10.0) 4 241245 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.59.1.el7.x86_64) 5 220798 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 6 219980 LISTES.ULAVAL.CA (Linux 3.10.0) 7 216100 LISTS.HAWAII.EDU (Linux 3.10.0-1160.83.1.el7.x86_64) 8 212970 LISTSERV.ACM.ORG (Windows Server 2016 Datacenter x64 Edition) 9 202744 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 10 197387 LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition) 11 173907 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 12 168466 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 13 168163 LISTS.UFL.EDU (Linux 2.6.32) 14 167511 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 15 152985 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 16 151355 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 17 137587 LISTSERV.UTORONTO.CA (Linux 3.10.0) 18 111152 LISTSERV.WUSTL.EDU (Windows Server 2016 Standard x64 Edition) 19 106634 LISTS.ROCHESTER.EDU (Windows Server 2012 R2 Standard x64 Edition) 20 105962 LIST.UVM.EDU (Linux 2.6.32)
Pos Subscribers Site --- ----------- ---- 1 5517530 LISTS.PSU.EDU (Linux 3.10.0) 2 4984604 LISTES.ULAVAL.CA (Linux 3.10.0) 3 1978906 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 4 1777535 LISTSERV.TAU.AC.IL (Linux 2.6.9) 5 1483278 LISTSERV.UTORONTO.CA (Linux 3.10.0) 6 1250886 LISTSERV.UA.EDU (Linux 4.12.14) 7 1134183 LISTSERV.TAMU.EDU (Linux 3.0.101) 8 1070135 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 9 1068422 LISTS.WAYNE.EDU (Linux 2.6.32) 10 1059036 LISTS.UFL.EDU (Linux 2.6.32) 11 936713 LISTS.UMN.EDU (Linux 3.10.0) 12 927745 LIST.MSU.EDU (Linux 3.10.0) 13 901333 LISTSERV.UH.EDU (Linux 3.10.0) 14 899129 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 15 853488 LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 841612 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 17 778400 LISTSERV.ECU.EDU (Windows Server 2016 Standard x64 Edition) 18 710032 LISTS.QUEENSU.CA (Linux 3.10.0) 19 708825 LISTSERV.LIV.AC.UK (Linux 3.10.0) 20 667792 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition)
Pos Lists Site --- ----- ---- 1 28515 LISTES.ULAVAL.CA (Linux 3.10.0) 2 16878 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 7232 LISTSERV.LIV.AC.UK (Linux 3.10.0) 8 6799 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 9 6581 LISTSERV.UTORONTO.CA (Linux 3.10.0) 10 5551 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 11 4965 LISTSERV.TAMU.EDU (Linux 3.0.101) 12 4860 LISTS.UMN.EDU (Linux 3.10.0) 13 4536 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 14 4393 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 15 3929 LISTS.QUEENSU.CA (Linux 3.10.0) 16 3613 LIST.UVM.EDU (Linux 2.6.32) 17 3578 LISTSERV.BROWN.EDU (Linux 3.10.0) 18 3341 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 19 2810 LISTSERV.KENT.EDU (Windows Server 2012 R2 Standard x64 Edition) 20 2775 LISTS.WAYNE.EDU (Linux 2.6.32)
Pos Recipients Site --- ---------- ---- 1 773983 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 419530 LISTSERV.LIV.AC.UK (Linux 3.10.0) 3 367205 LISTS.PSU.EDU (Linux 3.10.0) 4 241024 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.59.1.el7.x86_64) 5 219825 LISTES.ULAVAL.CA (Linux 3.10.0) 6 215699 LISTS.HAWAII.EDU (Linux 3.10.0-1160.83.1.el7.x86_64) 7 197997 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 8 197066 LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition) 9 170765 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 10 167274 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 11 165940 LISTS.UFL.EDU (Linux 2.6.32) 12 165178 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 13 161880 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 14 149459 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 15 148835 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 16 137501 LISTSERV.UTORONTO.CA (Linux 3.10.0) 17 104444 LIST.UVM.EDU (Linux 2.6.32) 18 102757 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 19 97169 LISTSERV.UA.EDU (Linux 4.12.14) 20 96773 LIST.MSU.EDU (Linux 3.10.0)
Pos Subscribers Site --- ----------- ---- 1 42984 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition) 2 41833 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 3 40477 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 29489 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 26422 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 24158 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 22304 L-AGSCINEWS@LISTS.PSU.EDU (Linux 3.10.0)