CTF servers

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

Server	Members	Online	Active
1 HackTheBoxverified	389,511	31,952	8.2%
2 TryHackMeverified	376,429	27,218	7.2%
3 OwlSecpartner	172,696	12,180	7.1%
4 JH Discord	30,379	2,982	9.8%
5 Root-Me	28,470	4,158	14.6%
6 OverTheWire	27,922	2,416	8.7%
7 SANS Holiday Hack Challenge	19,161	1,517	7.9%
8 ImaginaryCTF	14,151	1,650	11.7%
9 CTFlearn	12,077	842	7.0%
10 Hack This Fall Community	11,753	171	1.5%
11 CryptoHack	10,823	1,608	14.9%
12 crackmes.one	6,891	1,061	15.4%
13 SECCON Beginners CTF	6,733	825	12.3%
14 FCSC & Hackropole	6,078	734	12.1%
15 SkillBit (formerly MetaCTF)	6,063	860	14.2%
16 GoogleCTF	5,497	837	15.2%
17 SekaiCTF 2026	5,186	811	15.6%
18 TCP1P Server	4,844	567	11.7%
19 HITCON CTF	4,567	861	18.9%
20 Cyber Security Challenge Germany	4,280	225	5.3%
21 ångstromCTF	3,978	348	8.7%
22 VishwaCTF	3,942	99	2.5%
23 Real World CTF	3,734	277	7.4%
24 UIUCTF 2026	3,698	540	14.6%
25 SunshineCTF	3,663	338	9.2%
26 Midnight Sun CTF	3,589	769	21.4%
27 Hack United	3,582	192	5.4%
28 nullcon HackIM 2026	3,476	185	5.3%
29 ASIS CTF	3,438	324	9.4%
30 UTCTF 2026	3,398	360	10.6%
31 PatriotCTF 2026	3,349	358	10.7%
32 scriptCTF	3,252	248	7.6%
33 HeroCTF	3,208	224	7.0%
34 idekCTF	3,191	346	10.8%
35 247CTF	3,180	216	6.8%
36 NorthSec	3,137	687	21.9%
37 b01lersCTF	3,107	316	10.2%
38 UMassCTF 2026	3,041	318	10.5%
39 DEADFACE CTF	2,953	529	17.9%
40 BuckeyeCTF 2025	2,914	340	11.7%
41 corCTF	2,726	305	11.2%
42 KalmarCTF	2,720	522	19.2%
43 Hacking-Lab	2,718	201	7.4%
44 Kaspersky{CTF}	2,706	235	8.7%
45 Official HackMyVM	2,637	109	4.1%
46 HSCTF	2,636	184	7.0%
47 CrewCTF 2025	2,591	254	9.8%
48 KnightCTF	2,571	155	6.0%
49 TSG CTF	2,541	227	8.9%
50 smileyCTF 2025	2,491	266	10.7%
51 XCTF 10th–SCTF 2026	2,441	117	4.8%
52 GPN CTF 2026	2,421	277	11.4%
53 niteCTF '25	2,419	132	5.5%
54 rCTF	2,418	175	7.2%
55 Midnight Flag CTF - EXECUTION	2,336	218	9.3%
56 DIVER OSINT CTF	2,325	314	13.5%
57 HACKTORIA	2,214	238	10.7%
58 R3CTF 2026	2,183	292	13.4%
59 NNS CTF	2,131	353	16.6%
60 CCDC	2,117	805	38.0%
61 Hack.lu CTF	2,091	237	11.3%
62 1753CTF	2,087	145	6.9%
63 b01lers	2,087	181	8.7%
64 UMDCTF 2026	2,055	260	12.7%
65 HackTheBox_KE	2,034	27	1.3%
66 Dev Universe - FGTE CTF	1,919	114	5.9%
67 HackDay	1,911	109	5.7%
68 SECCON CTF 14	1,887	290	15.4%
69 BCACTF	1,866	165	8.8%
70 JerseyCTF 🔒	1,865	222	11.9%
71 CTF@CIT	1,855	150	8.1%
72 PrimeSec	1,809	95	5.3%
73 eCitadel	1,799	634	35.2%
74 Cyber Odyssey: Akasec CTF	1,786	49	2.7%
75 InCTF Nationals	1,773	26	1.5%
76 zer0pts CTF	1,770	194	11.0%
77 jailCTF 2026	1,757	176	10.0%
78 N0PSctf	1,732	168	9.7%
79 SECCON CTF 13	1,716	229	13.3%
80 IrisCTF	1,687	184	10.9%
81 PSU CCSO	1,614	131	8.1%
82 BlahajCTF	1,613	144	8.9%
83 HAXAGON Community	1,520	68	4.5%
84 pwnable.tw	1,516	156	10.3%
85 DamCTF	1,515	144	9.5%
86 ZeroDays CTF	1,451	58	4.0%
87 xCTFs	1,448	284	19.6%
88 TetCTF	1,426	135	9.5%
89 CyberDawgs Club	1,413	104	7.4%
90 ECW CTF	1,409	154	10.9%
91 TAMUctf 2026	1,393	179	12.8%
92 RITSEC CTF	1,384	184	13.3%
93 Reply CTF Challenge	1,380	48	3.5%
94 SECCON CTF 2023	1,358	150	11.0%
95 FAUST CTF 2026	1,349	164	12.2%
96 Sieberrsec CTF	1,297	148	11.4%
97 @Hack CTF - Concordia	1,295	87	6.7%
98 CyberSpace CTF 2024	1,285	121	9.4%
99 CakeCTF 2023	1,273	132	10.4%
100 hackerspace - DropCTF	1,273	131	10.3%
101 ISITDTU-CTF	1,253	110	8.8%
102 MontréHack	1,252	231	18.5%
103 Hack In The North	1,242	13	1.0%
104 SWIMMER OSINT CTF	1,232	176	14.3%
105 AlpacaHack	1,229	213	17.3%
106 UnitedCTF	1,220	261	21.4%
107 WaniCTF	1,216	150	12.3%
108 wpictf	1,184	39	3.3%
109 OmniCTF | Public	1,162	113	9.7%
110 DaVinciCTF	1,147	89	7.8%
111 HKCERT CTF 2024	1,119	110	9.8%
112 RingZer0 CTF	1,119	124	11.1%
113 Shutlock CTF 🕵	1,104	78	7.1%
114 NCKUCTF	1,099	294	26.8%
115 pingCTF 2026	1,099	89	8.1%
116 BDSec CTF	1,087	87	8.0%
117 Swiss Hacking Challenge	1,078	85	7.9%
118 RACTF	1,072	63	5.9%
119 Paradigm CTF	1,053	105	10.0%
120 ZishanHack	1,043	35	3.4%
121 HackTheMidlands	1,035	34	3.3%
122 squ1rrel CTF 2026	1,032	126	12.2%
123 x3CTF 2026	1,025	118	11.5%
124 Olympics CTF	1,000	75	7.5%
125 PearlCTF	990	71	7.2%
126 Pragyan CTF'26	988	85	8.6%
127 IRON CTF 2024	987	94	9.5%
128 SpookyCTF	974	95	9.8%
129 SwampCTF	944	91	9.6%
130 BERKE1337	943	86	9.1%
131 Break the Syntax CTF	937	108	11.5%
132 Arab & Africa Regional CTF	935	21	2.2%
133 pwnable.kr	932	120	12.9%
134 Swinburne Cyber Security Club (SCSC)	918	125	13.6%
135 World Wide Hack	910	76	8.4%
136 offsec	908	66	7.3%
137 P3rf3ctr00t CTF	901	62	6.9%
138 pwntools	890	96	10.8%
139 BRICS+ CTF	886	74	8.4%
140 Wargames.MY CTF 2024	886	71	8.0%
141 CyberSecurityRumble	884	113	12.8%
142 NewbieContest	881	51	5.8%
143 Otaku hunters	845	54	6.4%
144 RPISEC	835	96	11.5%
145 Wizer CTF	809	28	3.5%
146 DAMSEC CTF LEAGUE	798	156	19.5%
147 Cryptocracy™	795	23	2.9%
148 EnigmaXplore 3.0	773	36	4.7%
149 snakeCTF	772	119	15.4%
150 HACK'OSINT - CTF	762	116	15.2%