UUIDs

UUID V4

128 bits, 16 bytes, JSON format

122 bits of entropy, 5.31691198 × 1036 possible IDs

“...the odds of collision between any two is 1 in 2.71 x 1018 Put another way, one would need to generate 1 billion v4 UUIDs per second for 85 years to have a 50% chance of a single collision.”

What are the odds? by Jonathan Hall. 
2e549388-b45b-40e5-992a-3f3e6410b5c4
4ca2dc8e-9fbf-4320-884c-dfbadc2f1dd2
abdec883-a685-465a-8648-9b12c8eca85d
70711c95-5068-4f12-b826-718154d4884b
a0c30aef-cdb5-41ce-a08e-8cbb03af90bd
ae337bf7-3bd8-4d3f-8648-bce14f03f04e
e73baf8a-f9e9-4645-b070-2f7a5049bdce
eabadf65-40dd-4227-b88d-eb86cba63481
7f6be9f8-c229-4cca-b0d3-2b1ede30be8f
cf6ebb46-585f-4e78-8052-f93a3d08c1e8
1af98067-83c3-40f4-b51c-1b9b70be68cc
ec7a76d9-2763-4218-81d5-0a4aff2df47b
d0d67eeb-7508-4873-aa0b-2967c73ea3e9
b7e4db5a-b6df-49d7-abc1-2761d66241c1
107da90e-55c7-4819-b8a4-d4afbb6cc764
de130208-4323-4f0f-bad4-ec091dd682e4
41f44fb7-1f65-42c8-a2f1-aebb1bf69c44
ee033d89-99f6-4ac1-ad1b-bf33b17990ca
10d2f960-9368-46d2-8912-3fbdba8c07c2
43ec4cad-6bca-487b-9d60-188a5ba06414

Double UUID V4

256 bits, 32 bytes, 244 nits of entropy

2.8269553 × 1073 possible IDs 

84d56aac-7f72-4960-bd65-bfa200d465db-a750abe7-e8d0-431a-895a-a07622144da6
8c7f35d5-2ee9-4cab-b869-846387b23894-8db4e66c-8453-45fd-8054-fe803066207d
4e187c40-721f-4b55-b2f3-cef4e1fd703b-8bc93367-c497-4004-90f0-f7294e2f2d3d
544f43e0-e2ac-4233-a409-07372fc855ac-8aef10a2-beac-4af3-8fc8-235eb03cb38f
be45b962-0d08-426e-8a99-ee009621488f-e8113d59-50a7-4597-8695-c86b0bb8bce4
77bd9217-2971-453f-8339-6f0cafb0a442-cc1c8e54-e7a1-4ca4-ab6a-70fa40e9e067
52c2f6b3-0c3d-48fe-b3f0-f1a63ed75c24-e4b479a0-7261-4995-b072-0160d0469871
432ecb51-44b6-4c51-add8-f014ec50978d-3b63f593-d8e8-49db-bf85-9377b845a4c4
d9637339-50b5-4a91-b161-acfca84a4812-ba9f0be0-e720-4aca-a8b5-5fbe97d997b7
252e50a7-4846-459c-8e29-6c24b6d78071-9f5c0e22-7b34-4b21-937b-98bd002acc79
60e6408f-24fc-4293-baaf-7123cd179d93-740064f6-7a0b-4a7c-b8a9-f6a7593737bb
35320dc6-89cd-453a-ac7b-662047312fd5-f7ff943a-d74f-46dc-9cde-22db09b413dd
1b059947-bb52-44fd-b467-dfadfb7240c5-0fde032a-64ee-43f4-a178-35baf1848d68
a34887c9-9366-4363-aa99-768a5f2e4488-cc9a80d2-0d74-4de0-8a30-6d43815f51ce
3de822bb-83c2-4320-88f6-93cb7c929480-40230cfb-91a9-45e8-870d-274ccc4046f3
19f68424-f1c9-44bf-a850-0b07a100e519-b894bdf9-9348-4f9a-b466-47ea5dbca949
b881103e-fc92-4c43-b4ac-71a4a5aa29e4-b18512b0-11fa-40d1-9698-0f70f206bb4c
4b4f3f47-23ca-4252-a629-1f7fd5764e07-dd52e1b3-4dcb-48ab-a0c6-53e6fa1ebf1e
588ece6e-64f8-4d5e-afc2-a0b085bfc432-2b442e36-baef-4a3f-afe8-e722e0bc28de
e8d30dbe-817f-4f9d-a44d-1abf6b00d320-5cde5d05-f4f4-40fd-8296-0e5b3181d193

OLC IDs

Open Location Code (OLC) alphabet Ids. OLC is a geocoding system that encodes latitude and longitude into a short string of characters. The alphabet is simplified to use only uppercase letters and digits, excluding characters that can be easily confused (like '0' and 'O', '1' and 'I').

4,096,000,000,000,000 or 4.096 × 1015 possible IDs 

X7MC-GQ6R-QQVJ
9GRR-7J9V-5P3Q
4J8J-CF6F-39XF
GM6V-34W5-6P36
95J3-QG8M-M5PR
Q78X-GC7H-39HW
4F73-675V-RJW7
89RR-356P-P2W6
GGXH-QW84-CVW8
G8C2-79HC-98HV
G4X9-WPQP-3G9V
6GFG-PCWV-3XC8
V5MF-XCJX-PHH2
928W-48PQ-JGF4
WJ4H-2JXP-MCPM
CC27-HPRW-8MQ7
3G44-92FC-HGF6
9Q4M-MHHM-G9C2
88QX-VVM3-GXX8
MRFM-RXRV-X9XG