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Speed and call quality testTest delay, jitter and speed, with a focus on phone calls.My IP addressYour public IPv4 and IPv6 addresses, provider and address range.WhoIs lookupWho owns a domain or IP address, when it expires, and its DNS.DNS reportEvery DNS record for a domain, with email setup checked.IP subnet calculatorWork out a network's range, mask and hosts, and split it into subnets.

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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
fe88:2000::/20
First address
fe88:2000::
Last address
fe88:2fff: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
fe88:2000:0000:0000:0000:0000:0000:0000
Type
Link-local fe80::/10
Every IPv6 interface has one; not routed
Reverse DNS zone
2.8.8.e.f.ip6.arpa
Split into smaller subnets/28
/21 (2)/22 (4)/23 (8)/24 (16)/28 (256)/32 (4,096)/36 (65,536)

fe88:2000::/20 makes 256 subnets of /28.

Subnets
#SubnetLast address
1fe88:2000::/28fe88:200f:ffff:ffff:ffff:ffff:ffff:ffff
2fe88:2010::/28fe88:201f:ffff:ffff:ffff:ffff:ffff:ffff
3fe88:2020::/28fe88:202f:ffff:ffff:ffff:ffff:ffff:ffff
4fe88:2030::/28fe88:203f:ffff:ffff:ffff:ffff:ffff:ffff
5fe88:2040::/28fe88:204f:ffff:ffff:ffff:ffff:ffff:ffff
6fe88:2050::/28fe88:205f:ffff:ffff:ffff:ffff:ffff:ffff
7fe88:2060::/28fe88:206f:ffff:ffff:ffff:ffff:ffff:ffff
8fe88:2070::/28fe88:207f:ffff:ffff:ffff:ffff:ffff:ffff
9fe88:2080::/28fe88:208f:ffff:ffff:ffff:ffff:ffff:ffff
10fe88:2090::/28fe88:209f:ffff:ffff:ffff:ffff:ffff:ffff
11fe88:20a0::/28fe88:20af:ffff:ffff:ffff:ffff:ffff:ffff
12fe88:20b0::/28fe88:20bf:ffff:ffff:ffff:ffff:ffff:ffff
13fe88:20c0::/28fe88:20cf:ffff:ffff:ffff:ffff:ffff:ffff
14fe88:20d0::/28fe88:20df:ffff:ffff:ffff:ffff:ffff:ffff
15fe88:20e0::/28fe88:20ef:ffff:ffff:ffff:ffff:ffff:ffff
16fe88:20f0::/28fe88:20ff:ffff:ffff:ffff:ffff:ffff:ffff
17fe88:2100::/28fe88:210f:ffff:ffff:ffff:ffff:ffff:ffff
18fe88:2110::/28fe88:211f:ffff:ffff:ffff:ffff:ffff:ffff
19fe88:2120::/28fe88:212f:ffff:ffff:ffff:ffff:ffff:ffff
20fe88:2130::/28fe88:213f:ffff:ffff:ffff:ffff:ffff:ffff
21fe88:2140::/28fe88:214f:ffff:ffff:ffff:ffff:ffff:ffff
22fe88:2150::/28fe88:215f:ffff:ffff:ffff:ffff:ffff:ffff
23fe88:2160::/28fe88:216f:ffff:ffff:ffff:ffff:ffff:ffff
24fe88:2170::/28fe88:217f:ffff:ffff:ffff:ffff:ffff:ffff
25fe88:2180::/28fe88:218f:ffff:ffff:ffff:ffff:ffff:ffff
26fe88:2190::/28fe88:219f:ffff:ffff:ffff:ffff:ffff:ffff
27fe88:21a0::/28fe88:21af:ffff:ffff:ffff:ffff:ffff:ffff
28fe88:21b0::/28fe88:21bf:ffff:ffff:ffff:ffff:ffff:ffff
29fe88:21c0::/28fe88:21cf:ffff:ffff:ffff:ffff:ffff:ffff
30fe88:21d0::/28fe88:21df:ffff:ffff:ffff:ffff:ffff:ffff
31fe88:21e0::/28fe88:21ef:ffff:ffff:ffff:ffff:ffff:ffff
32fe88:21f0::/28fe88:21ff:ffff:ffff:ffff:ffff:ffff:ffff
33fe88:2200::/28fe88:220f:ffff:ffff:ffff:ffff:ffff:ffff
34fe88:2210::/28fe88:221f:ffff:ffff:ffff:ffff:ffff:ffff
35fe88:2220::/28fe88:222f:ffff:ffff:ffff:ffff:ffff:ffff
36fe88:2230::/28fe88:223f:ffff:ffff:ffff:ffff:ffff:ffff
37fe88:2240::/28fe88:224f:ffff:ffff:ffff:ffff:ffff:ffff
38fe88:2250::/28fe88:225f:ffff:ffff:ffff:ffff:ffff:ffff
39fe88:2260::/28fe88:226f:ffff:ffff:ffff:ffff:ffff:ffff
40fe88:2270::/28fe88:227f:ffff:ffff:ffff:ffff:ffff:ffff
41fe88:2280::/28fe88:228f:ffff:ffff:ffff:ffff:ffff:ffff
42fe88:2290::/28fe88:229f:ffff:ffff:ffff:ffff:ffff:ffff
43fe88:22a0::/28fe88:22af:ffff:ffff:ffff:ffff:ffff:ffff
44fe88:22b0::/28fe88:22bf:ffff:ffff:ffff:ffff:ffff:ffff
45fe88:22c0::/28fe88:22cf:ffff:ffff:ffff:ffff:ffff:ffff
46fe88:22d0::/28fe88:22df:ffff:ffff:ffff:ffff:ffff:ffff
47fe88:22e0::/28fe88:22ef:ffff:ffff:ffff:ffff:ffff:ffff
48fe88:22f0::/28fe88:22ff:ffff:ffff:ffff:ffff:ffff:ffff
49fe88:2300::/28fe88:230f:ffff:ffff:ffff:ffff:ffff:ffff
50fe88:2310::/28fe88:231f:ffff:ffff:ffff:ffff:ffff:ffff
51fe88:2320::/28fe88:232f:ffff:ffff:ffff:ffff:ffff:ffff
52fe88:2330::/28fe88:233f:ffff:ffff:ffff:ffff:ffff:ffff
53fe88:2340::/28fe88:234f:ffff:ffff:ffff:ffff:ffff:ffff
54fe88:2350::/28fe88:235f:ffff:ffff:ffff:ffff:ffff:ffff
55fe88:2360::/28fe88:236f:ffff:ffff:ffff:ffff:ffff:ffff
56fe88:2370::/28fe88:237f:ffff:ffff:ffff:ffff:ffff:ffff
57fe88:2380::/28fe88:238f:ffff:ffff:ffff:ffff:ffff:ffff
58fe88:2390::/28fe88:239f:ffff:ffff:ffff:ffff:ffff:ffff
59fe88:23a0::/28fe88:23af:ffff:ffff:ffff:ffff:ffff:ffff
60fe88:23b0::/28fe88:23bf:ffff:ffff:ffff:ffff:ffff:ffff
61fe88:23c0::/28fe88:23cf:ffff:ffff:ffff:ffff:ffff:ffff
62fe88:23d0::/28fe88:23df:ffff:ffff:ffff:ffff:ffff:ffff
63fe88:23e0::/28fe88:23ef:ffff:ffff:ffff:ffff:ffff:ffff
64fe88:23f0::/28fe88:23ff:ffff:ffff:ffff:ffff:ffff:ffff
65fe88:2400::/28fe88:240f:ffff:ffff:ffff:ffff:ffff:ffff
66fe88:2410::/28fe88:241f:ffff:ffff:ffff:ffff:ffff:ffff
67fe88:2420::/28fe88:242f:ffff:ffff:ffff:ffff:ffff:ffff
68fe88:2430::/28fe88:243f:ffff:ffff:ffff:ffff:ffff:ffff
69fe88:2440::/28fe88:244f:ffff:ffff:ffff:ffff:ffff:ffff
70fe88:2450::/28fe88:245f:ffff:ffff:ffff:ffff:ffff:ffff
71fe88:2460::/28fe88:246f:ffff:ffff:ffff:ffff:ffff:ffff
72fe88:2470::/28fe88:247f:ffff:ffff:ffff:ffff:ffff:ffff
73fe88:2480::/28fe88:248f:ffff:ffff:ffff:ffff:ffff:ffff
74fe88:2490::/28fe88:249f:ffff:ffff:ffff:ffff:ffff:ffff
75fe88:24a0::/28fe88:24af:ffff:ffff:ffff:ffff:ffff:ffff
76fe88:24b0::/28fe88:24bf:ffff:ffff:ffff:ffff:ffff:ffff
77fe88:24c0::/28fe88:24cf:ffff:ffff:ffff:ffff:ffff:ffff
78fe88:24d0::/28fe88:24df:ffff:ffff:ffff:ffff:ffff:ffff
79fe88:24e0::/28fe88:24ef:ffff:ffff:ffff:ffff:ffff:ffff
80fe88:24f0::/28fe88:24ff:ffff:ffff:ffff:ffff:ffff:ffff
81fe88:2500::/28fe88:250f:ffff:ffff:ffff:ffff:ffff:ffff
82fe88:2510::/28fe88:251f:ffff:ffff:ffff:ffff:ffff:ffff
83fe88:2520::/28fe88:252f:ffff:ffff:ffff:ffff:ffff:ffff
84fe88:2530::/28fe88:253f:ffff:ffff:ffff:ffff:ffff:ffff
85fe88:2540::/28fe88:254f:ffff:ffff:ffff:ffff:ffff:ffff
86fe88:2550::/28fe88:255f:ffff:ffff:ffff:ffff:ffff:ffff
87fe88:2560::/28fe88:256f:ffff:ffff:ffff:ffff:ffff:ffff
88fe88:2570::/28fe88:257f:ffff:ffff:ffff:ffff:ffff:ffff
89fe88:2580::/28fe88:258f:ffff:ffff:ffff:ffff:ffff:ffff
90fe88:2590::/28fe88:259f:ffff:ffff:ffff:ffff:ffff:ffff
91fe88:25a0::/28fe88:25af:ffff:ffff:ffff:ffff:ffff:ffff
92fe88:25b0::/28fe88:25bf:ffff:ffff:ffff:ffff:ffff:ffff
93fe88:25c0::/28fe88:25cf:ffff:ffff:ffff:ffff:ffff:ffff
94fe88:25d0::/28fe88:25df:ffff:ffff:ffff:ffff:ffff:ffff
95fe88:25e0::/28fe88:25ef:ffff:ffff:ffff:ffff:ffff:ffff
96fe88:25f0::/28fe88:25ff:ffff:ffff:ffff:ffff:ffff:ffff
97fe88:2600::/28fe88:260f:ffff:ffff:ffff:ffff:ffff:ffff
98fe88:2610::/28fe88:261f:ffff:ffff:ffff:ffff:ffff:ffff
99fe88:2620::/28fe88:262f:ffff:ffff:ffff:ffff:ffff:ffff
100fe88:2630::/28fe88:263f:ffff:ffff:ffff:ffff:ffff:ffff
101fe88:2640::/28fe88:264f:ffff:ffff:ffff:ffff:ffff:ffff
102fe88:2650::/28fe88:265f:ffff:ffff:ffff:ffff:ffff:ffff
103fe88:2660::/28fe88:266f:ffff:ffff:ffff:ffff:ffff:ffff
104fe88:2670::/28fe88:267f:ffff:ffff:ffff:ffff:ffff:ffff
105fe88:2680::/28fe88:268f:ffff:ffff:ffff:ffff:ffff:ffff
106fe88:2690::/28fe88:269f:ffff:ffff:ffff:ffff:ffff:ffff
107fe88:26a0::/28fe88:26af:ffff:ffff:ffff:ffff:ffff:ffff
108fe88:26b0::/28fe88:26bf:ffff:ffff:ffff:ffff:ffff:ffff
109fe88:26c0::/28fe88:26cf:ffff:ffff:ffff:ffff:ffff:ffff
110fe88:26d0::/28fe88:26df:ffff:ffff:ffff:ffff:ffff:ffff
111fe88:26e0::/28fe88:26ef:ffff:ffff:ffff:ffff:ffff:ffff
112fe88:26f0::/28fe88:26ff:ffff:ffff:ffff:ffff:ffff:ffff
113fe88:2700::/28fe88:270f:ffff:ffff:ffff:ffff:ffff:ffff
114fe88:2710::/28fe88:271f:ffff:ffff:ffff:ffff:ffff:ffff
115fe88:2720::/28fe88:272f:ffff:ffff:ffff:ffff:ffff:ffff
116fe88:2730::/28fe88:273f:ffff:ffff:ffff:ffff:ffff:ffff
117fe88:2740::/28fe88:274f:ffff:ffff:ffff:ffff:ffff:ffff
118fe88:2750::/28fe88:275f:ffff:ffff:ffff:ffff:ffff:ffff
119fe88:2760::/28fe88:276f:ffff:ffff:ffff:ffff:ffff:ffff
120fe88:2770::/28fe88:277f:ffff:ffff:ffff:ffff:ffff:ffff
121fe88:2780::/28fe88:278f:ffff:ffff:ffff:ffff:ffff:ffff
122fe88:2790::/28fe88:279f:ffff:ffff:ffff:ffff:ffff:ffff
123fe88:27a0::/28fe88:27af:ffff:ffff:ffff:ffff:ffff:ffff
124fe88:27b0::/28fe88:27bf:ffff:ffff:ffff:ffff:ffff:ffff
125fe88:27c0::/28fe88:27cf:ffff:ffff:ffff:ffff:ffff:ffff
126fe88:27d0::/28fe88:27df:ffff:ffff:ffff:ffff:ffff:ffff
127fe88:27e0::/28fe88:27ef:ffff:ffff:ffff:ffff:ffff:ffff
128fe88:27f0::/28fe88:27ff:ffff:ffff:ffff:ffff:ffff:ffff
129fe88:2800::/28fe88:280f:ffff:ffff:ffff:ffff:ffff:ffff
130fe88:2810::/28fe88:281f:ffff:ffff:ffff:ffff:ffff:ffff
131fe88:2820::/28fe88:282f:ffff:ffff:ffff:ffff:ffff:ffff
132fe88:2830::/28fe88:283f:ffff:ffff:ffff:ffff:ffff:ffff
133fe88:2840::/28fe88:284f:ffff:ffff:ffff:ffff:ffff:ffff
134fe88:2850::/28fe88:285f:ffff:ffff:ffff:ffff:ffff:ffff
135fe88:2860::/28fe88:286f:ffff:ffff:ffff:ffff:ffff:ffff
136fe88:2870::/28fe88:287f:ffff:ffff:ffff:ffff:ffff:ffff
137fe88:2880::/28fe88:288f:ffff:ffff:ffff:ffff:ffff:ffff
138fe88:2890::/28fe88:289f:ffff:ffff:ffff:ffff:ffff:ffff
139fe88:28a0::/28fe88:28af:ffff:ffff:ffff:ffff:ffff:ffff
140fe88:28b0::/28fe88:28bf:ffff:ffff:ffff:ffff:ffff:ffff
141fe88:28c0::/28fe88:28cf:ffff:ffff:ffff:ffff:ffff:ffff
142fe88:28d0::/28fe88:28df:ffff:ffff:ffff:ffff:ffff:ffff
143fe88:28e0::/28fe88:28ef:ffff:ffff:ffff:ffff:ffff:ffff
144fe88:28f0::/28fe88:28ff:ffff:ffff:ffff:ffff:ffff:ffff
145fe88:2900::/28fe88:290f:ffff:ffff:ffff:ffff:ffff:ffff
146fe88:2910::/28fe88:291f:ffff:ffff:ffff:ffff:ffff:ffff
147fe88:2920::/28fe88:292f:ffff:ffff:ffff:ffff:ffff:ffff
148fe88:2930::/28fe88:293f:ffff:ffff:ffff:ffff:ffff:ffff
149fe88:2940::/28fe88:294f:ffff:ffff:ffff:ffff:ffff:ffff
150fe88:2950::/28fe88:295f:ffff:ffff:ffff:ffff:ffff:ffff
151fe88:2960::/28fe88:296f:ffff:ffff:ffff:ffff:ffff:ffff
152fe88:2970::/28fe88:297f:ffff:ffff:ffff:ffff:ffff:ffff
153fe88:2980::/28fe88:298f:ffff:ffff:ffff:ffff:ffff:ffff
154fe88:2990::/28fe88:299f:ffff:ffff:ffff:ffff:ffff:ffff
155fe88:29a0::/28fe88:29af:ffff:ffff:ffff:ffff:ffff:ffff
156fe88:29b0::/28fe88:29bf:ffff:ffff:ffff:ffff:ffff:ffff
157fe88:29c0::/28fe88:29cf:ffff:ffff:ffff:ffff:ffff:ffff
158fe88:29d0::/28fe88:29df:ffff:ffff:ffff:ffff:ffff:ffff
159fe88:29e0::/28fe88:29ef:ffff:ffff:ffff:ffff:ffff:ffff
160fe88:29f0::/28fe88:29ff:ffff:ffff:ffff:ffff:ffff:ffff
161fe88:2a00::/28fe88:2a0f:ffff:ffff:ffff:ffff:ffff:ffff
162fe88:2a10::/28fe88:2a1f:ffff:ffff:ffff:ffff:ffff:ffff
163fe88:2a20::/28fe88:2a2f:ffff:ffff:ffff:ffff:ffff:ffff
164fe88:2a30::/28fe88:2a3f:ffff:ffff:ffff:ffff:ffff:ffff
165fe88:2a40::/28fe88:2a4f:ffff:ffff:ffff:ffff:ffff:ffff
166fe88:2a50::/28fe88:2a5f:ffff:ffff:ffff:ffff:ffff:ffff
167fe88:2a60::/28fe88:2a6f:ffff:ffff:ffff:ffff:ffff:ffff
168fe88:2a70::/28fe88:2a7f:ffff:ffff:ffff:ffff:ffff:ffff
169fe88:2a80::/28fe88:2a8f:ffff:ffff:ffff:ffff:ffff:ffff
170fe88:2a90::/28fe88:2a9f:ffff:ffff:ffff:ffff:ffff:ffff
171fe88:2aa0::/28fe88:2aaf:ffff:ffff:ffff:ffff:ffff:ffff
172fe88:2ab0::/28fe88:2abf:ffff:ffff:ffff:ffff:ffff:ffff
173fe88:2ac0::/28fe88:2acf:ffff:ffff:ffff:ffff:ffff:ffff
174fe88:2ad0::/28fe88:2adf:ffff:ffff:ffff:ffff:ffff:ffff
175fe88:2ae0::/28fe88:2aef:ffff:ffff:ffff:ffff:ffff:ffff
176fe88:2af0::/28fe88:2aff:ffff:ffff:ffff:ffff:ffff:ffff
177fe88:2b00::/28fe88:2b0f:ffff:ffff:ffff:ffff:ffff:ffff
178fe88:2b10::/28fe88:2b1f:ffff:ffff:ffff:ffff:ffff:ffff
179fe88:2b20::/28fe88:2b2f:ffff:ffff:ffff:ffff:ffff:ffff
180fe88:2b30::/28fe88:2b3f:ffff:ffff:ffff:ffff:ffff:ffff
181fe88:2b40::/28fe88:2b4f:ffff:ffff:ffff:ffff:ffff:ffff
182fe88:2b50::/28fe88:2b5f:ffff:ffff:ffff:ffff:ffff:ffff
183fe88:2b60::/28fe88:2b6f:ffff:ffff:ffff:ffff:ffff:ffff
184fe88:2b70::/28fe88:2b7f:ffff:ffff:ffff:ffff:ffff:ffff
185fe88:2b80::/28fe88:2b8f:ffff:ffff:ffff:ffff:ffff:ffff
186fe88:2b90::/28fe88:2b9f:ffff:ffff:ffff:ffff:ffff:ffff
187fe88:2ba0::/28fe88:2baf:ffff:ffff:ffff:ffff:ffff:ffff
188fe88:2bb0::/28fe88:2bbf:ffff:ffff:ffff:ffff:ffff:ffff
189fe88:2bc0::/28fe88:2bcf:ffff:ffff:ffff:ffff:ffff:ffff
190fe88:2bd0::/28fe88:2bdf:ffff:ffff:ffff:ffff:ffff:ffff
191fe88:2be0::/28fe88:2bef:ffff:ffff:ffff:ffff:ffff:ffff
192fe88:2bf0::/28fe88:2bff:ffff:ffff:ffff:ffff:ffff:ffff
193fe88:2c00::/28fe88:2c0f:ffff:ffff:ffff:ffff:ffff:ffff
194fe88:2c10::/28fe88:2c1f:ffff:ffff:ffff:ffff:ffff:ffff
195fe88:2c20::/28fe88:2c2f:ffff:ffff:ffff:ffff:ffff:ffff
196fe88:2c30::/28fe88:2c3f:ffff:ffff:ffff:ffff:ffff:ffff
197fe88:2c40::/28fe88:2c4f:ffff:ffff:ffff:ffff:ffff:ffff
198fe88:2c50::/28fe88:2c5f:ffff:ffff:ffff:ffff:ffff:ffff
199fe88:2c60::/28fe88:2c6f:ffff:ffff:ffff:ffff:ffff:ffff
200fe88:2c70::/28fe88:2c7f:ffff:ffff:ffff:ffff:ffff:ffff
201fe88:2c80::/28fe88:2c8f:ffff:ffff:ffff:ffff:ffff:ffff
202fe88:2c90::/28fe88:2c9f:ffff:ffff:ffff:ffff:ffff:ffff
203fe88:2ca0::/28fe88:2caf:ffff:ffff:ffff:ffff:ffff:ffff
204fe88:2cb0::/28fe88:2cbf:ffff:ffff:ffff:ffff:ffff:ffff
205fe88:2cc0::/28fe88:2ccf:ffff:ffff:ffff:ffff:ffff:ffff
206fe88:2cd0::/28fe88:2cdf:ffff:ffff:ffff:ffff:ffff:ffff
207fe88:2ce0::/28fe88:2cef:ffff:ffff:ffff:ffff:ffff:ffff
208fe88:2cf0::/28fe88:2cff:ffff:ffff:ffff:ffff:ffff:ffff
209fe88:2d00::/28fe88:2d0f:ffff:ffff:ffff:ffff:ffff:ffff
210fe88:2d10::/28fe88:2d1f:ffff:ffff:ffff:ffff:ffff:ffff
211fe88:2d20::/28fe88:2d2f:ffff:ffff:ffff:ffff:ffff:ffff
212fe88:2d30::/28fe88:2d3f:ffff:ffff:ffff:ffff:ffff:ffff
213fe88:2d40::/28fe88:2d4f:ffff:ffff:ffff:ffff:ffff:ffff
214fe88:2d50::/28fe88:2d5f:ffff:ffff:ffff:ffff:ffff:ffff
215fe88:2d60::/28fe88:2d6f:ffff:ffff:ffff:ffff:ffff:ffff
216fe88:2d70::/28fe88:2d7f:ffff:ffff:ffff:ffff:ffff:ffff
217fe88:2d80::/28fe88:2d8f:ffff:ffff:ffff:ffff:ffff:ffff
218fe88:2d90::/28fe88:2d9f:ffff:ffff:ffff:ffff:ffff:ffff
219fe88:2da0::/28fe88:2daf:ffff:ffff:ffff:ffff:ffff:ffff
220fe88:2db0::/28fe88:2dbf:ffff:ffff:ffff:ffff:ffff:ffff
221fe88:2dc0::/28fe88:2dcf:ffff:ffff:ffff:ffff:ffff:ffff
222fe88:2dd0::/28fe88:2ddf:ffff:ffff:ffff:ffff:ffff:ffff
223fe88:2de0::/28fe88:2def:ffff:ffff:ffff:ffff:ffff:ffff
224fe88:2df0::/28fe88:2dff:ffff:ffff:ffff:ffff:ffff:ffff
225fe88:2e00::/28fe88:2e0f:ffff:ffff:ffff:ffff:ffff:ffff
226fe88:2e10::/28fe88:2e1f:ffff:ffff:ffff:ffff:ffff:ffff
227fe88:2e20::/28fe88:2e2f:ffff:ffff:ffff:ffff:ffff:ffff
228fe88:2e30::/28fe88:2e3f:ffff:ffff:ffff:ffff:ffff:ffff
229fe88:2e40::/28fe88:2e4f:ffff:ffff:ffff:ffff:ffff:ffff
230fe88:2e50::/28fe88:2e5f:ffff:ffff:ffff:ffff:ffff:ffff
231fe88:2e60::/28fe88:2e6f:ffff:ffff:ffff:ffff:ffff:ffff
232fe88:2e70::/28fe88:2e7f:ffff:ffff:ffff:ffff:ffff:ffff
233fe88:2e80::/28fe88:2e8f:ffff:ffff:ffff:ffff:ffff:ffff
234fe88:2e90::/28fe88:2e9f:ffff:ffff:ffff:ffff:ffff:ffff
235fe88:2ea0::/28fe88:2eaf:ffff:ffff:ffff:ffff:ffff:ffff
236fe88:2eb0::/28fe88:2ebf:ffff:ffff:ffff:ffff:ffff:ffff
237fe88:2ec0::/28fe88:2ecf:ffff:ffff:ffff:ffff:ffff:ffff
238fe88:2ed0::/28fe88:2edf:ffff:ffff:ffff:ffff:ffff:ffff
239fe88:2ee0::/28fe88:2eef:ffff:ffff:ffff:ffff:ffff:ffff
240fe88:2ef0::/28fe88:2eff:ffff:ffff:ffff:ffff:ffff:ffff
241fe88:2f00::/28fe88:2f0f:ffff:ffff:ffff:ffff:ffff:ffff
242fe88:2f10::/28fe88:2f1f:ffff:ffff:ffff:ffff:ffff:ffff
243fe88:2f20::/28fe88:2f2f:ffff:ffff:ffff:ffff:ffff:ffff
244fe88:2f30::/28fe88:2f3f:ffff:ffff:ffff:ffff:ffff:ffff
245fe88:2f40::/28fe88:2f4f:ffff:ffff:ffff:ffff:ffff:ffff
246fe88:2f50::/28fe88:2f5f:ffff:ffff:ffff:ffff:ffff:ffff
247fe88:2f60::/28fe88:2f6f:ffff:ffff:ffff:ffff:ffff:ffff
248fe88:2f70::/28fe88:2f7f:ffff:ffff:ffff:ffff:ffff:ffff
249fe88:2f80::/28fe88:2f8f:ffff:ffff:ffff:ffff:ffff:ffff
250fe88:2f90::/28fe88:2f9f:ffff:ffff:ffff:ffff:ffff:ffff
251fe88:2fa0::/28fe88:2faf:ffff:ffff:ffff:ffff:ffff:ffff
252fe88:2fb0::/28fe88:2fbf:ffff:ffff:ffff:ffff:ffff:ffff
253fe88:2fc0::/28fe88:2fcf:ffff:ffff:ffff:ffff:ffff:ffff
254fe88:2fd0::/28fe88:2fdf:ffff:ffff:ffff:ffff:ffff:ffff
255fe88:2fe0::/28fe88:2fef:ffff:ffff:ffff:ffff:ffff:ffff
256fe88:2ff0::/28fe88:2fff: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.