UUID V4

128 bits, 16 bytes

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.”

6cbb2fab-cb64-473a-afa7-64778a59ef39
a31d375d-8b85-46ca-aeb2-441def3b76a3
2579b291-4a02-4637-ae0f-c8ab48cea94c
7bffca9c-d977-4cc7-99eb-cfb069f5460a
1fc11fb6-3341-4a21-9f17-0f03204b2a59
1d2832cf-076d-4594-96a3-915ebdbd8602
1206362f-702f-4386-b334-1be7fff6faf7
8a5766b3-ef3e-4e66-939e-c4c4d969304c
9b65779c-be82-4b3f-a401-4056fdb2397c
4474a4f9-bc24-42dc-8dda-46a658e7966c
    

OLC IDs

16 characters, 16 bytes (15 random characters + 1 check character)

64.829 bits of entropy (15 random characters), 3.2768 × 10¹⁹ possible IDs

Enough for about 3.8 billion unique IDs for every living person (~8.3 billion) and company (~377 million) on Earth. The average American opens between 60 and 90 unique financial accounts. For financially active individuals or those optimizing rewards and interest yields, this figure routinely exceeds 100 accounts.

About OLC IDs and the checksum

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').

The 16th character is a checksum: a Luhn mod 20 check character computed from the first 15. Each character is mapped to its position in the alphabet 23456789CFGHJMPQRVWX (2 = 0 through X = 19). Moving right to left, every other value is doubled, starting with the rightmost; a doubled value of 20 or more has 19 subtracted (the sum of its base-20 digits). The values are added up, and the check character is the one at position (20 − (sum mod 20)) mod 20. It catches any single mistyped character and most swaps of two adjacent characters. Hyphens are ignored.

8M2X-42V2-GV98-2XV7
JF89-J9MJ-HWF2-86C7
C6P9-C2Q5-65MR-RW9Q
92Q5-7C4R-326F-7CR6
7838-HM29-9823-Q984
M848-HW3J-7W2R-4C8P
QQPJ-3J5F-XQ78-W36C
8MWQ-M62F-2C8F-GVV3
7WJR-J7X8-2WQ5-CJWX
HF4F-PQ5X-R5CG-WQFP
    

Double UUID V4

256 bits, 32 bytes

244 bits of entropy, 2.8269553 × 10⁷³ possible IDs

ea8879a5-dfc6-4356-8ec8-f385cfce3cee-7d46f928-7951-4d4b-ae75-6acabf9c377a
3f429f1d-ee38-4122-96ae-24a55f1d50ca-7347937f-2b84-44d2-83cb-fbf79a845690
b58f8307-d284-4152-975e-497fabf26a0e-93e32ecb-93dd-44ec-a440-2e43733b052d
eee72750-6d7e-494d-aac2-7573e8ccabed-2a97e182-8d48-4dd9-beb7-5211abd3c88b
67bae5da-a6e9-4a90-aca5-bbfc769eba58-55939e52-4a29-4ff8-8cdf-09e484be7bfd
7917211e-944d-472a-8d45-676476248115-fe6ffb75-2f4e-4fa0-aa8a-828dd4edc73d
b7d0e544-59c2-4d41-99fe-f170441d2a6b-617818f3-c265-4e65-adbe-bcd6cef199ce
5b66b1f9-76b8-4df0-995a-39f557a3f762-d6b92ff1-df6c-4330-8688-be5acb086464
9aa7662a-653f-4093-968a-d9bae6c10588-0afdd295-5880-4d8d-b30a-dcad51a37a13
6897024b-9380-4a56-92a1-f5352a56f817-d89e5b93-7dfb-4ad3-9083-77cb8bf19571
    

UUID V7

Unix ms timestamp (48-bit), random bits (74-bit total). Sortable by time.

Excellent DB performance (sequential inserts); sortable; no MAC leakage. Database primary keys; distributed systems. Recommended for most modern apps/DBs.

01a15903-4eb3-778b-8d6e-4c11d7a05feb
01a15903-4eb4-75bd-9bbe-38fa6d8934a6
01a15903-4eb4-75bd-9bbe-42f4c113a75a
01a15903-4eb4-75bd-9bbe-4b6a8007ad23
01a15903-4eb4-75bd-9bbe-531efdd7e707
01a15903-4eb4-75bd-9bbe-59cd4f687b69
01a15903-4eb4-75bd-9bbe-6023998414d7
01a15903-4eb4-75bd-9bbe-6b66368389f2
01a15903-4eb4-75bd-9bbe-71d60e99abc3
01a15903-4eb4-75bd-9bbe-79c725044b02
    

Names (Short)

Randomly generated people names.

Fara Georgeanne
Shela Nicholle
Brinn Amata
Junina Honor
Terri Lavinia
Laryssa Susie
Francisca Angelina
Kamilah Lenna
Kathlin Valerye
Trix Emmie
    

Names (Long)

Randomly generated people names.

Bride Debi Davine
Mallorie Loria Danyette
Winnie Jania Edi
Lelah Adrianna Hadria
Delphine Mareah Cammy
Latashia Coral Lu
Yoko Imelda Darda
Mireille Constancia Lucy
Salaidh Mathilde Adrianna
Caria Lucila Geri
    

Countries

Randomly generated country names.

Serbia
Cocos Islands
Suriname
Turkey
Japan
Peru
Antigua & Barbuda
Honduras
Nicaragua
Barbados
    

Passwords

Randomly generated secure passwords.

$d(TTv=BIJ55m%Cj*^$d
vMF}W&Df,Uc^-=@6mGk]
nBGy-A]^dcc.JCBRYVTi
IG7ynP_R^h^N,RAnO-dG
-mp)NXbCW[V*|i&0-KLa
%W1j[v&X@%k)pH[NC:Q9
SDwE}YA9C}hT.O8q)WCN
^I%OjaiMK2AXMmyrG8CX
uo{tz-oS0HOUdHDl,]Lq
WmB@|&e^xjbKf)?WfY*k
    

Process Folder Names

Sequentially generated process, human-readable, folder names.

20261020-111231-625QXQ
20261020-111231-C24H33
20261020-111231-HW734V
20261020-111231-4885XH
20261020-111231-6C95GM
20261020-111231-9CHMFF
20261020-111231-P3732F
20261020-111231-HRGH76
20261020-111231-MWVVR4
20261020-111231-5JHF2P
    

Google-like IDs

Randomly generated Google-like 'sub' IDs.

476881035576188961156
942340720075293784844
264315270894963086327
052371635873630085171
486476121723304379842
490941606465102717754
886584637889264399621
478775800760503751049
882894545962482328125
167065737979407966469
    

Unix Timestamps

Randomly generated Unix timestamps from the past 2 months.

1789395064
1788336701
1788626045
1789474639
1792368969
1791167871
1789906771
1789920219
1792446664
1790762456
    

GUIDs

Randomly generated GUIDs using the Base64 alphabet.

dACXzVqw6-I2
ku0foHgVS1bU
yv-NwAbMluAB
qvnUZkJXPHZc
6oB6f7YAC0Ju
y2CDxk7i3qnh
D3q24qGGY0Xx
jKwsrrlE9Np_
Xz3B6_9jhbIY
xg2j5o5yjIbG
    

Randomly generated OLC IDs.

Secure 128-bit random IDs, using the Open Location Code (OLC) alphabet. 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').

GXQJ3RR3JGW975QC4FH5CXR84GGV9Q
RQ3MHMXC2HJF82P85Q9Q4G3QJJ7M88
3233QWWX688589842HMJG34Q5FRM74
FR427WRFJCMVHFGCWP4W9G8JXP5829
4P2G7J2H6QXR3GX5VP35C3523M9J4M
57MM4HXVCGFW9CH45X22M7HFQR4VX9
QMV6QHFWW9658VGWXV6HV866X2VCGX
G8JJM7CFGRXWMR2XR4966V5MP9X64P
7Q3C5FWQCJ4CVG9MPVMWCG7RVXC5GG
M63QJPCG9P633JX6P7W6HF7FXP96XG
    

Encrypted URL IDs (GUID)

Base64URL encoded encrypted V7 UUID tokens. Each token packs an 8-byte random IV plus a UUIDv7 XOR-masked with an HMAC-SHA256 keystream derived from the IV and a private key, so the token is opaque and non-sequential in URLs but still reversible to recover the original UUIDv7 (and its embedded timestamp) server-side.

H4N3wcjovRHVNSzsO9xa7nNpfopOU_px
J6Kebj1qoBJVJRHWpD7DkwNt3ACdEwhM
u3aMerya11lFPaBcLCjjBSD1Z6CJOrma
Cmir3PGdDgcOOCyhwLdZ5Bzya__OcyiL
wH8jGi_fladlbPp2IlnmQrpQHDTQ9t2M
X3zfqYlBhciMdqxDUt1fQTHYRzwIX2mq
zPA9_IJK-aL5mH2IV-8qFvUBhP2vrgAR
hdyPfLGsj71sjb_TJqcjf2cHu28LS7sw
CVoSELXvcxpBTLlW7U0r_kgXV9EJk1Hy
2MRsM8AaoTw120xgwD8NLmcZHvrnoiQi