CTF servers

150 measured server(s) with the CTF sub-topic, ranked by real members. Browse topics →

Server	Members	Online	Active
1 HackTheBoxverified	387,172	39,228	10.1%
2 TryHackMeverified	374,223	34,422	9.2%
3 OwlSecpartner	167,834	17,456	10.4%
4 JH Discord	30,262	3,591	11.9%
5 Root-Me	28,410	4,776	16.8%
6 OverTheWire	27,738	2,670	9.6%
7 SANS Holiday Hack Challenge	19,214	1,783	9.3%
8 ImaginaryCTF	14,162	1,886	13.3%
9 CTFlearn	12,099	1,042	8.6%
10 Hack This Fall Community	11,778	167	1.4%
11 CryptoHack	10,787	1,664	15.4%
12 crackmes.one	6,776	1,361	20.1%
13 SECCON Beginners CTF	6,749	596	8.8%
14 FCSC & Hackropole	6,100	863	14.1%
15 SkillBit (formerly MetaCTF)	6,072	918	15.1%
16 GoogleCTF	5,537	937	16.9%
17 SekaiCTF 2026	5,243	1,136	21.7%
18 TCP1P Server	4,738	521	11.0%
19 Cyber Security Challenge Germany	4,304	699	16.2%
20 HITCON CTF	4,052	725	17.9%
21 VishwaCTF	4,020	208	5.2%
22 ångstromCTF	3,995	357	8.9%
23 UIUCTF 2026	3,749	669	17.8%
24 Real World CTF	3,748	299	8.0%
25 Midnight Sun CTF	3,629	679	18.7%
26 Hack United	3,538	213	6.0%
27 nullcon HackIM 2026	3,499	255	7.3%
28 ASIS CTF	3,451	617	17.9%
29 UTCTF 2026	3,426	361	10.5%
30 PatriotCTF 2026	3,379	567	16.8%
31 scriptCTF	3,291	338	10.3%
32 HeroCTF	3,241	514	15.9%
33 idekCTF	3,214	328	10.2%
34 247CTF	3,188	236	7.4%
35 NorthSec	3,148	609	19.3%
36 b01lersCTF	3,131	324	10.3%
37 SunshineCTF	3,092	347	11.2%
38 UMassCTF 2026	3,073	351	11.4%
39 BuckeyeCTF 2025	2,934	508	17.3%
40 Kaspersky{CTF}	2,753	257	9.3%
41 KalmarCTF	2,743	576	21.0%
42 corCTF	2,742	310	11.3%
43 Hacking-Lab	2,734	192	7.0%
44 HSCTF	2,640	186	7.0%
45 Official HackMyVM	2,630	125	4.8%
46 CrewCTF 2025	2,606	318	12.2%
47 KnightCTF	2,598	223	8.6%
48 TSG CTF	2,556	211	8.3%
49 smileyCTF 2025	2,512	321	12.8%
50 GPN CTF 2026	2,455	240	9.8%
51 niteCTF '25	2,447	181	7.4%
52 XCTF 10th–SCTF 2026	2,447	95	3.9%
53 rCTF	2,421	166	6.9%
54 Midnight Flag CTF - EXECUTION	2,368	588	24.8%
55 DIVER OSINT CTF	2,345	289	12.3%
56 NNS CTF	2,205	394	17.9%
57 R3CTF 2026	2,205	292	13.2%
58 HACKTORIA	2,167	260	12.0%
59 UMDCTF 2026	2,117	346	16.3%
60 1753CTF	2,108	244	11.6%
61 b01lers	2,075	334	16.1%
62 CCDC	2,026	601	29.7%
63 HackTheBox_KE	2,017	62	3.1%
64 JerseyCTF 🔒	1,967	260	13.2%
65 DEADFACE CTF	1,966	241	12.3%
66 Hack.lu CTF	1,941	291	15.0%
67 HackDay	1,921	316	16.4%
68 Dev Universe - FGTE CTF	1,916	156	8.1%
69 SECCON CTF 14	1,909	301	15.8%
70 BCACTF	1,888	202	10.7%
71 CTF@CIT	1,876	193	10.3%
72 eCitadel	1,813	372	20.5%
73 jailCTF 2026	1,796	222	12.4%
74 Cyber Odyssey: Akasec CTF	1,792	149	8.3%
75 zer0pts CTF	1,775	195	11.0%
76 InCTF Nationals	1,765	81	4.6%
77 N0PSctf	1,748	181	10.4%
78 SECCON CTF 13	1,724	219	12.7%
79 IrisCTF	1,703	194	11.4%
80 Equinor CTF	1,662	313	18.8%
81 PSU CCSO	1,619	182	11.2%
82 BlahajCTF	1,602	75	4.7%
83 HAXAGON Community	1,534	291	19.0%
84 DamCTF	1,532	192	12.5%
85 pwnable.tw	1,518	178	11.7%
86 ZeroDays CTF	1,469	207	14.1%
87 ECW CTF	1,435	266	18.5%
88 TetCTF	1,433	131	9.1%
89 TAMUctf 2026	1,413	241	17.1%
90 xCTFs	1,406	275	19.6%
91 CyberDawgs Club	1,403	209	14.9%
92 RITSEC CTF	1,398	178	12.7%
93 Reply CTF Challenge	1,388	86	6.2%
94 SECCON CTF 2023	1,363	167	12.3%
95 Sieberrsec CTF	1,309	199	15.2%
96 @Hack CTF - Concordia	1,300	153	11.8%
97 CyberSpace CTF 2024	1,298	122	9.4%
98 hackerspace - DropCTF	1,280	126	9.8%
99 CakeCTF 2023	1,279	115	9.0%
100 ISITDTU-CTF	1,262	93	7.4%
101 MontréHack	1,256	192	15.3%
102 Hack In The North	1,242	16	1.3%
103 SWIMMER OSINT CTF	1,241	141	11.4%
104 AlpacaHack	1,224	181	14.8%
105 WaniCTF	1,222	193	15.8%
106 wpictf	1,185	49	4.1%
107 OmniCTF | Public	1,174	86	7.3%
108 DaVinciCTF	1,150	129	11.2%
109 UnitedCTF	1,138	207	18.2%
110 HKCERT CTF 2024	1,129	101	8.9%
111 Shutlock CTF 🕵	1,119	183	16.4%
112 RingZer0 CTF	1,116	157	14.1%
113 pingCTF 2026	1,109	120	10.8%
114 BDSec CTF	1,103	105	9.5%
115 FAUST CTF 2026	1,094	197	18.0%
116 NCKUCTF	1,086	222	20.4%
117 Swiss Hacking Challenge	1,082	82	7.6%
118 RACTF	1,072	88	8.2%
119 Paradigm CTF	1,061	118	11.1%
120 squ1rrel CTF 2026	1,042	151	14.5%
121 HackTheMidlands	1,039	90	8.7%
122 ZishanHack	1,038	35	3.4%
123 Olympics CTF	1,033	82	7.9%
124 x3CTF 2026	1,017	187	18.4%
125 IRON CTF 2024	1,008	66	6.5%
126 Pragyan CTF'26	1,003	67	6.7%
127 PearlCTF	997	105	10.5%
128 SwampCTF	950	108	11.4%
129 Break the Syntax CTF	943	136	14.4%
130 SpookyCTF	941	128	13.6%
131 Arab & Africa Regional CTF	939	50	5.3%
132 BERKE1337	938	104	11.1%
133 Swinburne Cyber Security Club (SCSC)	923	44	4.8%
134 pwnable.kr	920	125	13.6%
135 offsec	908	69	7.6%
136 P3rf3ctr00t CTF	905	75	8.3%
137 World Wide Hack	904	96	10.6%
138 BRICS+ CTF	894	83	9.3%
139 pwntools	893	126	14.1%
140 Wargames.MY CTF 2024	889	100	11.2%
141 CyberSecurityRumble	887	109	12.3%
142 NewbieContest	887	120	13.5%
143 Otaku hunters	840	73	8.7%
144 RPISEC	816	148	18.1%
145 Wizer CTF	814	54	6.6%
146 Cryptocracy™	795	32	4.0%
147 07CTF	785	88	11.2%
148 EnigmaXplore 3.0	781	31	4.0%
149 snakeCTF	780	113	14.5%
150 HACK'OSINT - CTF	766	113	14.8%