Open email survey (2020)

This year's scan was done via shodan. Approximately 40-50% of the internet was scanned

Current status

Number of IMAP servers found:3856785
Number of servers detected using banner text:3588116 (93%)
Number of servers detected using command replies:3674586 (95%)
Number of conflicting banner vs. reply detections:227

Software used by IMAP servers:

SoftwareCount2020 %points diff2019
%
2018
%
2017
%
2016
%
2014
%
2013
%
2012
%
Dovecot296695576.93+0.7176.2275.0971.2568.5057.1652.8748.37
Courier3065887.95-1.119.069.9612.3417.0023.4227.1430.70
IdeaImapServer1468893.81+0.153.663.273.523.172.672.872.35
MailEnable692871.80+0.171.631.631.960.971.611.431.28
NetArt593581.54+0.141.401.161.711.951.691.561.25
Exchange495301.28-0.151.431.531.771.572.852.963.27
Zimbra378670.98-0.041.020.960.930.940.900.810.59
hMailServer278280.72+0.010.710.740.770.590.850.790.77
Cyrus225580.58-0.030.610.620.680.670.941.021.18
Hurricane Electric221240.57+0.070.500.510.620.420.610.560.00
Kerio214540.56-0.040.600.560.540.550.640.610.61
SmarterMail204750.53+0.010.520.540.620.380.700.690.78
MDaemon189670.49-0.010.500.500.610.350.770.750.79
(Unknown)121970.32+0.050.270.320.240.150.360.511.06
UW-IMAP99050.26-0.040.300.340.650.912.052.323.21
IceWarp78290.20-0.020.220.210.270.250.370.390.44
nginx75390.20+0.050.150.120.080.070.060.050.00
Bigfoot62290.16+0.100.060.130.030.330.240.240.36
Winmail56520.15+0.100.050.060.050.050.060.050.05
IMail56130.15-0.010.160.180.240.170.370.440.57
CommuniGate Pro55320.14-0.010.150.190.220.180.270.270.31
Domino28450.07-0.010.080.090.110.080.160.170.44
Coremail24580.06+-00.060.050.040.040.030.020.01
(Not IMAP protocol)20860.05-0.060.110.670.040.030.110.130.03
Surgemail19140.05+-00.050.050.080.080.080.090.12
Perdition15810.04+-00.040.040.050.050.030.190.17
GImap15760.04+0.010.030.030.010.030.030.030.03
Axigen14880.04+-00.040.040.040.040.050.050.04
Zarafa11070.03-0.010.040.050.070.080.110.100.09
David.fx10750.03+-00.030.030.040.020.030.030.03
GroupWise7490.02+-00.020.020.030.030.060.070.09
MailStore6770.02+-00.020.010.010.010.010.000.00
T36240.02+-00.020.020.040.010.010.010.00
InSciTek6130.02+-00.020.020.020.010.050.060.05
Mercury5840.02+-00.020.020.020.010.030.030.03
dbmail5440.01+-00.010.020.020.020.040.040.05
imapfront5150.01-0.010.020.020.020.040.090.120.20
Synametrics4850.01+-00.010.010.010.010.010.010.00
Gordano4610.01+-00.010.010.010.010.020.020.04
Citadel4210.01-0.010.020.020.020.030.040.050.04
Binc3920.01+-00.010.010.020.020.030.030.05
MailSite3790.01+-00.010.020.030.020.040.040.04
EmailArchitect3110.01+-00.010.010.000.000.010.010.01
modusMail2430.01+-00.010.010.010.010.030.020.04
Oracle CMES2190.01+-00.010.010.010.010.020.020.03
Ability2100.01+-00.010.010.010.010.010.010.02
James2000.01+-00.010.020.010.000.010.000.00
VPOP31800.00+-00.000.000.010.000.010.010.01
WinWebMail1780.00+-00.000.010.010.010.010.010.01
FirstClass1750.00-0.010.010.010.010.010.020.020.02
EIMS1710.00+-00.000.010.010.010.010.010.02
TurboMail1610.00+-00.000.000.000.000.010.010.01
ArGoSoft1450.00+-00.000.010.010.010.020.010.02
DeskNow1160.00+-00.000.000.010.010.010.010.02
MailNow!1130.00+-00.000.000.000.000.000.000.00
CallPilot1070.00+-00.000.000.010.010.020.020.02
EVO1040.00+-00.000.000.000.000.000.000.00
mail.ru1030.00+-00.000.000.000.000.000.000.00
DEEPMail910.00+-00.000.000.000.000.000.000.00
Office-Logic InterChange870.00+-00.000.000.000.000.000.000.00
AMTANGEE860.00+-00.000.000.000.000.000.000.00
Scalix850.00+-00.000.000.000.010.010.010.02
OpenWave750.00+-00.000.000.000.000.000.000.00
iSCREAM580.00+-00.000.000.000.000.000.000.00
Critical Path540.00+-00.000.000.000.000.000.000.00
CrediMail520.00+-00.000.000.000.000.000.000.00
Mailtraq510.00+-00.000.000.000.000.010.010.01
JanaServer500.00+-00.000.000.000.000.000.000.00
UMSS490.00+-00.000.000.000.000.000.000.00
UnknownProxy480.00+-00.000.000.000.010.010.010.00
EarthLink460.00+-00.000.000.000.000.000.000.00
imapproxy340.00+-00.000.000.000.000.010.010.00
Hmail340.00+-00.000.000.000.000.000.000.00
Tmailer230.00+-00.000.000.000.000.000.000.00
Mirapoint230.00+-00.000.000.000.000.000.010.01
Archiveopteryx210.00+-00.000.000.000.000.000.000.00
CUE210.00+-00.000.000.000.000.000.000.00
Mercur200.00+-00.000.000.000.000.000.000.00
ExpressMail180.00+-00.000.000.000.000.000.000.00
QuarkMail110.00+-00.000.000.000.000.000.000.15
TimeMaker100.00+-00.000.000.000.000.000.000.00
KEN!100.00+-00.000.000.000.000.000.000.00
SmartMax90.00+-00.000.000.000.000.010.010.01
SPA-PRO80.00+-00.000.000.000.000.000.000.00
hgigamail50.00+-00.000.000.000.000.000.000.00
Softalk50.00+-00.000.000.000.000.000.000.00
TIMS30.00+-00.000.000.000.000.000.000.00
Isode30.00+-00.000.000.000.000.000.000.00
Oracle Beehive30.00+-00.000.000.000.000.000.000.00
NPlex20.00+-00.000.000.000.000.000.000.00
PMDF20.00+-00.000.000.000.000.000.000.00
MuseMail10.00+-00.000.000.000.000.000.000.00
TeamWARE10.00+-00.000.000.000.000.000.000.00