On 116 servers with real players from the Steam list. Checked 21:24 UTC.
most played now: zm_foda
Zombie servers run Zombie Plague, Biohazard or a similar mod. At the start of the round one or a few players turn into zombies, and every human they hit becomes one too. The humans hold corners and high ground and spend ammo packs on weapons and items; the round ends when everyone is infected or the time runs out. zm_ maps are made for it, and ze_ maps for the escape version, where the humans run through the level with the zombies behind them.
Over the last 30 days Zombie servers had 973 real players at any moment on average - 18% of everyone on CS 1.6 Steam servers, #2 of 14 game modes. Right now 1,113 people play Zombie on 116 servers, most of them on servers in Germany and France. The maps with the most players at the moment: zm_foda, zm_fodadcm, zm_ice_attack3. The busiest time is Sunday around 19:00 UTC, the quietest Wednesday around 10:00 UTC.
131.196.196.196:2702032/32Real players162.222.16.154:2701832/32Real players91.121.62.188:2701529/32Real players51.254.25.223:2701529/32Real players5.135.170.121:2701529/32Real players51.254.25.223:2701629/32Real players145.239.231.46:2701528/32Real players135.125.147.173:2701728/32Real players163.5.26.42:2701527/32Real players130.110.17.181:2701525/32Real players51.83.85.37:2701525/32Real players92.118.207.11:2701621/32Real players87.98.156.203:2701521/32Real players151.247.205.250:2704220/32Real players172.96.140.62:424819/32Real players37.187.9.34:2702519/32Real players195.60.166.224:2737418/32Real players81.181.244.137:2701518/32Real players131.196.196.197:2708017/32Real players104.234.65.245:2720017/32Real playersRight now 1,113, on 116 servers from the Steam server list. Over the last 30 days it was 973 on average at any moment. Fake servers and bots are not counted.
By real players right now: Fantasy Gaming | Zombie Escape | FreeVIP+CSO+Events (32 players), [mXe] ZombiePlague + Niveles [1] MxEMexico.com (32 players), ZP.LEVSAN.COM | Zombie Plague XP Mode, Levels, VIP (29 players). The full list is below, and every server has a page with its history.
On Sunday around 19:00 UTC. The grid above shows every hour of the week in your own time zone.