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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Prefix/20
Addresses2^108
/64 networks2^44
Network
fc07:e000::/20
First address
fc07:e000::
Last address
fc07:efff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
324,518,553,658,426,726,783,156,020,576,256 (2^108)
/64 networks (LANs)
17,592,186,044,416 (2^44)
Full form
fc07:e000:0000:0000:0000:0000:0000:0000
Type
Unique local (ULA) fc00::/7
Private IPv6, like RFC 1918; usually fd00::/8
Reverse DNS zone
e.7.0.c.f.ip6.arpa
Split into smaller subnets/28
/21 (2)/22 (4)/23 (8)/24 (16)/28 (256)/32 (4,096)/36 (65,536)

fc07:e000::/20 makes 256 subnets of /28.

Subnets
#SubnetLast address
1fc07:e000::/28fc07:e00f:ffff:ffff:ffff:ffff:ffff:ffff
2fc07:e010::/28fc07:e01f:ffff:ffff:ffff:ffff:ffff:ffff
3fc07:e020::/28fc07:e02f:ffff:ffff:ffff:ffff:ffff:ffff
4fc07:e030::/28fc07:e03f:ffff:ffff:ffff:ffff:ffff:ffff
5fc07:e040::/28fc07:e04f:ffff:ffff:ffff:ffff:ffff:ffff
6fc07:e050::/28fc07:e05f:ffff:ffff:ffff:ffff:ffff:ffff
7fc07:e060::/28fc07:e06f:ffff:ffff:ffff:ffff:ffff:ffff
8fc07:e070::/28fc07:e07f:ffff:ffff:ffff:ffff:ffff:ffff
9fc07:e080::/28fc07:e08f:ffff:ffff:ffff:ffff:ffff:ffff
10fc07:e090::/28fc07:e09f:ffff:ffff:ffff:ffff:ffff:ffff
11fc07:e0a0::/28fc07:e0af:ffff:ffff:ffff:ffff:ffff:ffff
12fc07:e0b0::/28fc07:e0bf:ffff:ffff:ffff:ffff:ffff:ffff
13fc07:e0c0::/28fc07:e0cf:ffff:ffff:ffff:ffff:ffff:ffff
14fc07:e0d0::/28fc07:e0df:ffff:ffff:ffff:ffff:ffff:ffff
15fc07:e0e0::/28fc07:e0ef:ffff:ffff:ffff:ffff:ffff:ffff
16fc07:e0f0::/28fc07:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
17fc07:e100::/28fc07:e10f:ffff:ffff:ffff:ffff:ffff:ffff
18fc07:e110::/28fc07:e11f:ffff:ffff:ffff:ffff:ffff:ffff
19fc07:e120::/28fc07:e12f:ffff:ffff:ffff:ffff:ffff:ffff
20fc07:e130::/28fc07:e13f:ffff:ffff:ffff:ffff:ffff:ffff
21fc07:e140::/28fc07:e14f:ffff:ffff:ffff:ffff:ffff:ffff
22fc07:e150::/28fc07:e15f:ffff:ffff:ffff:ffff:ffff:ffff
23fc07:e160::/28fc07:e16f:ffff:ffff:ffff:ffff:ffff:ffff
24fc07:e170::/28fc07:e17f:ffff:ffff:ffff:ffff:ffff:ffff
25fc07:e180::/28fc07:e18f:ffff:ffff:ffff:ffff:ffff:ffff
26fc07:e190::/28fc07:e19f:ffff:ffff:ffff:ffff:ffff:ffff
27fc07:e1a0::/28fc07:e1af:ffff:ffff:ffff:ffff:ffff:ffff
28fc07:e1b0::/28fc07:e1bf:ffff:ffff:ffff:ffff:ffff:ffff
29fc07:e1c0::/28fc07:e1cf:ffff:ffff:ffff:ffff:ffff:ffff
30fc07:e1d0::/28fc07:e1df:ffff:ffff:ffff:ffff:ffff:ffff
31fc07:e1e0::/28fc07:e1ef:ffff:ffff:ffff:ffff:ffff:ffff
32fc07:e1f0::/28fc07:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
33fc07:e200::/28fc07:e20f:ffff:ffff:ffff:ffff:ffff:ffff
34fc07:e210::/28fc07:e21f:ffff:ffff:ffff:ffff:ffff:ffff
35fc07:e220::/28fc07:e22f:ffff:ffff:ffff:ffff:ffff:ffff
36fc07:e230::/28fc07:e23f:ffff:ffff:ffff:ffff:ffff:ffff
37fc07:e240::/28fc07:e24f:ffff:ffff:ffff:ffff:ffff:ffff
38fc07:e250::/28fc07:e25f:ffff:ffff:ffff:ffff:ffff:ffff
39fc07:e260::/28fc07:e26f:ffff:ffff:ffff:ffff:ffff:ffff
40fc07:e270::/28fc07:e27f:ffff:ffff:ffff:ffff:ffff:ffff
41fc07:e280::/28fc07:e28f:ffff:ffff:ffff:ffff:ffff:ffff
42fc07:e290::/28fc07:e29f:ffff:ffff:ffff:ffff:ffff:ffff
43fc07:e2a0::/28fc07:e2af:ffff:ffff:ffff:ffff:ffff:ffff
44fc07:e2b0::/28fc07:e2bf:ffff:ffff:ffff:ffff:ffff:ffff
45fc07:e2c0::/28fc07:e2cf:ffff:ffff:ffff:ffff:ffff:ffff
46fc07:e2d0::/28fc07:e2df:ffff:ffff:ffff:ffff:ffff:ffff
47fc07:e2e0::/28fc07:e2ef:ffff:ffff:ffff:ffff:ffff:ffff
48fc07:e2f0::/28fc07:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
49fc07:e300::/28fc07:e30f:ffff:ffff:ffff:ffff:ffff:ffff
50fc07:e310::/28fc07:e31f:ffff:ffff:ffff:ffff:ffff:ffff
51fc07:e320::/28fc07:e32f:ffff:ffff:ffff:ffff:ffff:ffff
52fc07:e330::/28fc07:e33f:ffff:ffff:ffff:ffff:ffff:ffff
53fc07:e340::/28fc07:e34f:ffff:ffff:ffff:ffff:ffff:ffff
54fc07:e350::/28fc07:e35f:ffff:ffff:ffff:ffff:ffff:ffff
55fc07:e360::/28fc07:e36f:ffff:ffff:ffff:ffff:ffff:ffff
56fc07:e370::/28fc07:e37f:ffff:ffff:ffff:ffff:ffff:ffff
57fc07:e380::/28fc07:e38f:ffff:ffff:ffff:ffff:ffff:ffff
58fc07:e390::/28fc07:e39f:ffff:ffff:ffff:ffff:ffff:ffff
59fc07:e3a0::/28fc07:e3af:ffff:ffff:ffff:ffff:ffff:ffff
60fc07:e3b0::/28fc07:e3bf:ffff:ffff:ffff:ffff:ffff:ffff
61fc07:e3c0::/28fc07:e3cf:ffff:ffff:ffff:ffff:ffff:ffff
62fc07:e3d0::/28fc07:e3df:ffff:ffff:ffff:ffff:ffff:ffff
63fc07:e3e0::/28fc07:e3ef:ffff:ffff:ffff:ffff:ffff:ffff
64fc07:e3f0::/28fc07:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
65fc07:e400::/28fc07:e40f:ffff:ffff:ffff:ffff:ffff:ffff
66fc07:e410::/28fc07:e41f:ffff:ffff:ffff:ffff:ffff:ffff
67fc07:e420::/28fc07:e42f:ffff:ffff:ffff:ffff:ffff:ffff
68fc07:e430::/28fc07:e43f:ffff:ffff:ffff:ffff:ffff:ffff
69fc07:e440::/28fc07:e44f:ffff:ffff:ffff:ffff:ffff:ffff
70fc07:e450::/28fc07:e45f:ffff:ffff:ffff:ffff:ffff:ffff
71fc07:e460::/28fc07:e46f:ffff:ffff:ffff:ffff:ffff:ffff
72fc07:e470::/28fc07:e47f:ffff:ffff:ffff:ffff:ffff:ffff
73fc07:e480::/28fc07:e48f:ffff:ffff:ffff:ffff:ffff:ffff
74fc07:e490::/28fc07:e49f:ffff:ffff:ffff:ffff:ffff:ffff
75fc07:e4a0::/28fc07:e4af:ffff:ffff:ffff:ffff:ffff:ffff
76fc07:e4b0::/28fc07:e4bf:ffff:ffff:ffff:ffff:ffff:ffff
77fc07:e4c0::/28fc07:e4cf:ffff:ffff:ffff:ffff:ffff:ffff
78fc07:e4d0::/28fc07:e4df:ffff:ffff:ffff:ffff:ffff:ffff
79fc07:e4e0::/28fc07:e4ef:ffff:ffff:ffff:ffff:ffff:ffff
80fc07:e4f0::/28fc07:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
81fc07:e500::/28fc07:e50f:ffff:ffff:ffff:ffff:ffff:ffff
82fc07:e510::/28fc07:e51f:ffff:ffff:ffff:ffff:ffff:ffff
83fc07:e520::/28fc07:e52f:ffff:ffff:ffff:ffff:ffff:ffff
84fc07:e530::/28fc07:e53f:ffff:ffff:ffff:ffff:ffff:ffff
85fc07:e540::/28fc07:e54f:ffff:ffff:ffff:ffff:ffff:ffff
86fc07:e550::/28fc07:e55f:ffff:ffff:ffff:ffff:ffff:ffff
87fc07:e560::/28fc07:e56f:ffff:ffff:ffff:ffff:ffff:ffff
88fc07:e570::/28fc07:e57f:ffff:ffff:ffff:ffff:ffff:ffff
89fc07:e580::/28fc07:e58f:ffff:ffff:ffff:ffff:ffff:ffff
90fc07:e590::/28fc07:e59f:ffff:ffff:ffff:ffff:ffff:ffff
91fc07:e5a0::/28fc07:e5af:ffff:ffff:ffff:ffff:ffff:ffff
92fc07:e5b0::/28fc07:e5bf:ffff:ffff:ffff:ffff:ffff:ffff
93fc07:e5c0::/28fc07:e5cf:ffff:ffff:ffff:ffff:ffff:ffff
94fc07:e5d0::/28fc07:e5df:ffff:ffff:ffff:ffff:ffff:ffff
95fc07:e5e0::/28fc07:e5ef:ffff:ffff:ffff:ffff:ffff:ffff
96fc07:e5f0::/28fc07:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
97fc07:e600::/28fc07:e60f:ffff:ffff:ffff:ffff:ffff:ffff
98fc07:e610::/28fc07:e61f:ffff:ffff:ffff:ffff:ffff:ffff
99fc07:e620::/28fc07:e62f:ffff:ffff:ffff:ffff:ffff:ffff
100fc07:e630::/28fc07:e63f:ffff:ffff:ffff:ffff:ffff:ffff
101fc07:e640::/28fc07:e64f:ffff:ffff:ffff:ffff:ffff:ffff
102fc07:e650::/28fc07:e65f:ffff:ffff:ffff:ffff:ffff:ffff
103fc07:e660::/28fc07:e66f:ffff:ffff:ffff:ffff:ffff:ffff
104fc07:e670::/28fc07:e67f:ffff:ffff:ffff:ffff:ffff:ffff
105fc07:e680::/28fc07:e68f:ffff:ffff:ffff:ffff:ffff:ffff
106fc07:e690::/28fc07:e69f:ffff:ffff:ffff:ffff:ffff:ffff
107fc07:e6a0::/28fc07:e6af:ffff:ffff:ffff:ffff:ffff:ffff
108fc07:e6b0::/28fc07:e6bf:ffff:ffff:ffff:ffff:ffff:ffff
109fc07:e6c0::/28fc07:e6cf:ffff:ffff:ffff:ffff:ffff:ffff
110fc07:e6d0::/28fc07:e6df:ffff:ffff:ffff:ffff:ffff:ffff
111fc07:e6e0::/28fc07:e6ef:ffff:ffff:ffff:ffff:ffff:ffff
112fc07:e6f0::/28fc07:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
113fc07:e700::/28fc07:e70f:ffff:ffff:ffff:ffff:ffff:ffff
114fc07:e710::/28fc07:e71f:ffff:ffff:ffff:ffff:ffff:ffff
115fc07:e720::/28fc07:e72f:ffff:ffff:ffff:ffff:ffff:ffff
116fc07:e730::/28fc07:e73f:ffff:ffff:ffff:ffff:ffff:ffff
117fc07:e740::/28fc07:e74f:ffff:ffff:ffff:ffff:ffff:ffff
118fc07:e750::/28fc07:e75f:ffff:ffff:ffff:ffff:ffff:ffff
119fc07:e760::/28fc07:e76f:ffff:ffff:ffff:ffff:ffff:ffff
120fc07:e770::/28fc07:e77f:ffff:ffff:ffff:ffff:ffff:ffff
121fc07:e780::/28fc07:e78f:ffff:ffff:ffff:ffff:ffff:ffff
122fc07:e790::/28fc07:e79f:ffff:ffff:ffff:ffff:ffff:ffff
123fc07:e7a0::/28fc07:e7af:ffff:ffff:ffff:ffff:ffff:ffff
124fc07:e7b0::/28fc07:e7bf:ffff:ffff:ffff:ffff:ffff:ffff
125fc07:e7c0::/28fc07:e7cf:ffff:ffff:ffff:ffff:ffff:ffff
126fc07:e7d0::/28fc07:e7df:ffff:ffff:ffff:ffff:ffff:ffff
127fc07:e7e0::/28fc07:e7ef:ffff:ffff:ffff:ffff:ffff:ffff
128fc07:e7f0::/28fc07:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
129fc07:e800::/28fc07:e80f:ffff:ffff:ffff:ffff:ffff:ffff
130fc07:e810::/28fc07:e81f:ffff:ffff:ffff:ffff:ffff:ffff
131fc07:e820::/28fc07:e82f:ffff:ffff:ffff:ffff:ffff:ffff
132fc07:e830::/28fc07:e83f:ffff:ffff:ffff:ffff:ffff:ffff
133fc07:e840::/28fc07:e84f:ffff:ffff:ffff:ffff:ffff:ffff
134fc07:e850::/28fc07:e85f:ffff:ffff:ffff:ffff:ffff:ffff
135fc07:e860::/28fc07:e86f:ffff:ffff:ffff:ffff:ffff:ffff
136fc07:e870::/28fc07:e87f:ffff:ffff:ffff:ffff:ffff:ffff
137fc07:e880::/28fc07:e88f:ffff:ffff:ffff:ffff:ffff:ffff
138fc07:e890::/28fc07:e89f:ffff:ffff:ffff:ffff:ffff:ffff
139fc07:e8a0::/28fc07:e8af:ffff:ffff:ffff:ffff:ffff:ffff
140fc07:e8b0::/28fc07:e8bf:ffff:ffff:ffff:ffff:ffff:ffff
141fc07:e8c0::/28fc07:e8cf:ffff:ffff:ffff:ffff:ffff:ffff
142fc07:e8d0::/28fc07:e8df:ffff:ffff:ffff:ffff:ffff:ffff
143fc07:e8e0::/28fc07:e8ef:ffff:ffff:ffff:ffff:ffff:ffff
144fc07:e8f0::/28fc07:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
145fc07:e900::/28fc07:e90f:ffff:ffff:ffff:ffff:ffff:ffff
146fc07:e910::/28fc07:e91f:ffff:ffff:ffff:ffff:ffff:ffff
147fc07:e920::/28fc07:e92f:ffff:ffff:ffff:ffff:ffff:ffff
148fc07:e930::/28fc07:e93f:ffff:ffff:ffff:ffff:ffff:ffff
149fc07:e940::/28fc07:e94f:ffff:ffff:ffff:ffff:ffff:ffff
150fc07:e950::/28fc07:e95f:ffff:ffff:ffff:ffff:ffff:ffff
151fc07:e960::/28fc07:e96f:ffff:ffff:ffff:ffff:ffff:ffff
152fc07:e970::/28fc07:e97f:ffff:ffff:ffff:ffff:ffff:ffff
153fc07:e980::/28fc07:e98f:ffff:ffff:ffff:ffff:ffff:ffff
154fc07:e990::/28fc07:e99f:ffff:ffff:ffff:ffff:ffff:ffff
155fc07:e9a0::/28fc07:e9af:ffff:ffff:ffff:ffff:ffff:ffff
156fc07:e9b0::/28fc07:e9bf:ffff:ffff:ffff:ffff:ffff:ffff
157fc07:e9c0::/28fc07:e9cf:ffff:ffff:ffff:ffff:ffff:ffff
158fc07:e9d0::/28fc07:e9df:ffff:ffff:ffff:ffff:ffff:ffff
159fc07:e9e0::/28fc07:e9ef:ffff:ffff:ffff:ffff:ffff:ffff
160fc07:e9f0::/28fc07:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
161fc07:ea00::/28fc07:ea0f:ffff:ffff:ffff:ffff:ffff:ffff
162fc07:ea10::/28fc07:ea1f:ffff:ffff:ffff:ffff:ffff:ffff
163fc07:ea20::/28fc07:ea2f:ffff:ffff:ffff:ffff:ffff:ffff
164fc07:ea30::/28fc07:ea3f:ffff:ffff:ffff:ffff:ffff:ffff
165fc07:ea40::/28fc07:ea4f:ffff:ffff:ffff:ffff:ffff:ffff
166fc07:ea50::/28fc07:ea5f:ffff:ffff:ffff:ffff:ffff:ffff
167fc07:ea60::/28fc07:ea6f:ffff:ffff:ffff:ffff:ffff:ffff
168fc07:ea70::/28fc07:ea7f:ffff:ffff:ffff:ffff:ffff:ffff
169fc07:ea80::/28fc07:ea8f:ffff:ffff:ffff:ffff:ffff:ffff
170fc07:ea90::/28fc07:ea9f:ffff:ffff:ffff:ffff:ffff:ffff
171fc07:eaa0::/28fc07:eaaf:ffff:ffff:ffff:ffff:ffff:ffff
172fc07:eab0::/28fc07:eabf:ffff:ffff:ffff:ffff:ffff:ffff
173fc07:eac0::/28fc07:eacf:ffff:ffff:ffff:ffff:ffff:ffff
174fc07:ead0::/28fc07:eadf:ffff:ffff:ffff:ffff:ffff:ffff
175fc07:eae0::/28fc07:eaef:ffff:ffff:ffff:ffff:ffff:ffff
176fc07:eaf0::/28fc07:eaff:ffff:ffff:ffff:ffff:ffff:ffff
177fc07:eb00::/28fc07:eb0f:ffff:ffff:ffff:ffff:ffff:ffff
178fc07:eb10::/28fc07:eb1f:ffff:ffff:ffff:ffff:ffff:ffff
179fc07:eb20::/28fc07:eb2f:ffff:ffff:ffff:ffff:ffff:ffff
180fc07:eb30::/28fc07:eb3f:ffff:ffff:ffff:ffff:ffff:ffff
181fc07:eb40::/28fc07:eb4f:ffff:ffff:ffff:ffff:ffff:ffff
182fc07:eb50::/28fc07:eb5f:ffff:ffff:ffff:ffff:ffff:ffff
183fc07:eb60::/28fc07:eb6f:ffff:ffff:ffff:ffff:ffff:ffff
184fc07:eb70::/28fc07:eb7f:ffff:ffff:ffff:ffff:ffff:ffff
185fc07:eb80::/28fc07:eb8f:ffff:ffff:ffff:ffff:ffff:ffff
186fc07:eb90::/28fc07:eb9f:ffff:ffff:ffff:ffff:ffff:ffff
187fc07:eba0::/28fc07:ebaf:ffff:ffff:ffff:ffff:ffff:ffff
188fc07:ebb0::/28fc07:ebbf:ffff:ffff:ffff:ffff:ffff:ffff
189fc07:ebc0::/28fc07:ebcf:ffff:ffff:ffff:ffff:ffff:ffff
190fc07:ebd0::/28fc07:ebdf:ffff:ffff:ffff:ffff:ffff:ffff
191fc07:ebe0::/28fc07:ebef:ffff:ffff:ffff:ffff:ffff:ffff
192fc07:ebf0::/28fc07:ebff:ffff:ffff:ffff:ffff:ffff:ffff
193fc07:ec00::/28fc07:ec0f:ffff:ffff:ffff:ffff:ffff:ffff
194fc07:ec10::/28fc07:ec1f:ffff:ffff:ffff:ffff:ffff:ffff
195fc07:ec20::/28fc07:ec2f:ffff:ffff:ffff:ffff:ffff:ffff
196fc07:ec30::/28fc07:ec3f:ffff:ffff:ffff:ffff:ffff:ffff
197fc07:ec40::/28fc07:ec4f:ffff:ffff:ffff:ffff:ffff:ffff
198fc07:ec50::/28fc07:ec5f:ffff:ffff:ffff:ffff:ffff:ffff
199fc07:ec60::/28fc07:ec6f:ffff:ffff:ffff:ffff:ffff:ffff
200fc07:ec70::/28fc07:ec7f:ffff:ffff:ffff:ffff:ffff:ffff
201fc07:ec80::/28fc07:ec8f:ffff:ffff:ffff:ffff:ffff:ffff
202fc07:ec90::/28fc07:ec9f:ffff:ffff:ffff:ffff:ffff:ffff
203fc07:eca0::/28fc07:ecaf:ffff:ffff:ffff:ffff:ffff:ffff
204fc07:ecb0::/28fc07:ecbf:ffff:ffff:ffff:ffff:ffff:ffff
205fc07:ecc0::/28fc07:eccf:ffff:ffff:ffff:ffff:ffff:ffff
206fc07:ecd0::/28fc07:ecdf:ffff:ffff:ffff:ffff:ffff:ffff
207fc07:ece0::/28fc07:ecef:ffff:ffff:ffff:ffff:ffff:ffff
208fc07:ecf0::/28fc07:ecff:ffff:ffff:ffff:ffff:ffff:ffff
209fc07:ed00::/28fc07:ed0f:ffff:ffff:ffff:ffff:ffff:ffff
210fc07:ed10::/28fc07:ed1f:ffff:ffff:ffff:ffff:ffff:ffff
211fc07:ed20::/28fc07:ed2f:ffff:ffff:ffff:ffff:ffff:ffff
212fc07:ed30::/28fc07:ed3f:ffff:ffff:ffff:ffff:ffff:ffff
213fc07:ed40::/28fc07:ed4f:ffff:ffff:ffff:ffff:ffff:ffff
214fc07:ed50::/28fc07:ed5f:ffff:ffff:ffff:ffff:ffff:ffff
215fc07:ed60::/28fc07:ed6f:ffff:ffff:ffff:ffff:ffff:ffff
216fc07:ed70::/28fc07:ed7f:ffff:ffff:ffff:ffff:ffff:ffff
217fc07:ed80::/28fc07:ed8f:ffff:ffff:ffff:ffff:ffff:ffff
218fc07:ed90::/28fc07:ed9f:ffff:ffff:ffff:ffff:ffff:ffff
219fc07:eda0::/28fc07:edaf:ffff:ffff:ffff:ffff:ffff:ffff
220fc07:edb0::/28fc07:edbf:ffff:ffff:ffff:ffff:ffff:ffff
221fc07:edc0::/28fc07:edcf:ffff:ffff:ffff:ffff:ffff:ffff
222fc07:edd0::/28fc07:eddf:ffff:ffff:ffff:ffff:ffff:ffff
223fc07:ede0::/28fc07:edef:ffff:ffff:ffff:ffff:ffff:ffff
224fc07:edf0::/28fc07:edff:ffff:ffff:ffff:ffff:ffff:ffff
225fc07:ee00::/28fc07:ee0f:ffff:ffff:ffff:ffff:ffff:ffff
226fc07:ee10::/28fc07:ee1f:ffff:ffff:ffff:ffff:ffff:ffff
227fc07:ee20::/28fc07:ee2f:ffff:ffff:ffff:ffff:ffff:ffff
228fc07:ee30::/28fc07:ee3f:ffff:ffff:ffff:ffff:ffff:ffff
229fc07:ee40::/28fc07:ee4f:ffff:ffff:ffff:ffff:ffff:ffff
230fc07:ee50::/28fc07:ee5f:ffff:ffff:ffff:ffff:ffff:ffff
231fc07:ee60::/28fc07:ee6f:ffff:ffff:ffff:ffff:ffff:ffff
232fc07:ee70::/28fc07:ee7f:ffff:ffff:ffff:ffff:ffff:ffff
233fc07:ee80::/28fc07:ee8f:ffff:ffff:ffff:ffff:ffff:ffff
234fc07:ee90::/28fc07:ee9f:ffff:ffff:ffff:ffff:ffff:ffff
235fc07:eea0::/28fc07:eeaf:ffff:ffff:ffff:ffff:ffff:ffff
236fc07:eeb0::/28fc07:eebf:ffff:ffff:ffff:ffff:ffff:ffff
237fc07:eec0::/28fc07:eecf:ffff:ffff:ffff:ffff:ffff:ffff
238fc07:eed0::/28fc07:eedf:ffff:ffff:ffff:ffff:ffff:ffff
239fc07:eee0::/28fc07:eeef:ffff:ffff:ffff:ffff:ffff:ffff
240fc07:eef0::/28fc07:eeff:ffff:ffff:ffff:ffff:ffff:ffff
241fc07:ef00::/28fc07:ef0f:ffff:ffff:ffff:ffff:ffff:ffff
242fc07:ef10::/28fc07:ef1f:ffff:ffff:ffff:ffff:ffff:ffff
243fc07:ef20::/28fc07:ef2f:ffff:ffff:ffff:ffff:ffff:ffff
244fc07:ef30::/28fc07:ef3f:ffff:ffff:ffff:ffff:ffff:ffff
245fc07:ef40::/28fc07:ef4f:ffff:ffff:ffff:ffff:ffff:ffff
246fc07:ef50::/28fc07:ef5f:ffff:ffff:ffff:ffff:ffff:ffff
247fc07:ef60::/28fc07:ef6f:ffff:ffff:ffff:ffff:ffff:ffff
248fc07:ef70::/28fc07:ef7f:ffff:ffff:ffff:ffff:ffff:ffff
249fc07:ef80::/28fc07:ef8f:ffff:ffff:ffff:ffff:ffff:ffff
250fc07:ef90::/28fc07:ef9f:ffff:ffff:ffff:ffff:ffff:ffff
251fc07:efa0::/28fc07:efaf:ffff:ffff:ffff:ffff:ffff:ffff
252fc07:efb0::/28fc07:efbf:ffff:ffff:ffff:ffff:ffff:ffff
253fc07:efc0::/28fc07:efcf:ffff:ffff:ffff:ffff:ffff:ffff
254fc07:efd0::/28fc07:efdf:ffff:ffff:ffff:ffff:ffff:ffff
255fc07:efe0::/28fc07:efef:ffff:ffff:ffff:ffff:ffff:ffff
256fc07:eff0::/28fc07:efff:ffff:ffff:ffff:ffff:ffff:ffff

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.