Security & QA
Random String Generator (Alphanumeric, Passwords & Secrets)
Generate cryptographically strong random strings, API secrets, and QA stress testing tokens with custom character sets and entropy calculations.
Open ToolUUID / GUID Generator (RFC 4122 v4 Bulk Generator)
Generate RFC 4122 compliant version-4 UUIDs / GUIDs instantly using cryptographically secure Web Crypto PRNG. Download clean JSON or TXT lists.
#1
a665bb97-ca7c-4af8-acee-7aab7bf00e28#2
552b3072-6c23-4a27-9c3b-2ba346a42612#3
67c80534-bd1b-4ea1-9094-b85c702e5a12#4
9f445d9b-f2d8-4f54-8cab-062151403e86#5
6038aa83-e5a8-4c9e-a356-23ce1b50a2f9#6
9c45ec28-ff18-49f5-ab64-3953048d65d1#7
c7cd8331-5d7d-49bb-bbe3-c5a2f4e3128c#8
9f684802-b8a7-4d2b-931b-84ef0d17ee61#9
acc8ad22-0997-409b-9e28-b8e1c1ce2b02#10
ea503d7b-df5b-439c-b135-5a0d0bee7779
⚡ Automated Database Seeding
Automate UUID / GUID Seeding & Database Migrations
Generate 1,000+ RFC 4122 compliant version-4 GUIDs and stream them directly into database migrations and test fixtures.
How to Generate RFC 4122 v4 UUIDs
1
Choose Quantity & Case
Select how many UUIDs you need (1, 10, 50, 100, or 500) and choose lowercase or UPPERCASE.
2
Set Format Preferences
Optionally strip hyphens for 32 character hexadecimal format or enclose in curly braces (GUID).
3
Copy or Export Data
Click Generate to produce unique IDs. Copy all with one click or export as structured JSON or raw TXT.
Key Features of UUID / GUID Generator
RFC 4122 v4 Compliant
Guarantees strictly standard version-4 UUIDs with bit-level compliance (variant 10xx, version 0100).
Native crypto.randomUUID()
Powered directly by native browser cryptographic hardware entropy for zero collisions.
Bulk Generation Up to 500
Generate high-volume batches of 500 unique IDs in under 10 milliseconds.
Dual JSON & TXT Exports
Download clean JSON arrays for API fixtures or raw plain text files for test automation suites.
RFC 4122 v4 Specifications & Format Reference
Technical breakdown of 128-bit pseudorandom identifiers, bit layout compliance, and formatting variants.
| Format / Variant | Structure & Pattern | Total Bits / Entropy | Primary Use Case |
|---|---|---|---|
| Standard RFC 4122 v4 | 8-4-4-4-12 (e.g., xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx) | 122 random bits | Database primary keys, distributed tracing, REST APIs |
| GUID (Microsoft Style) | Braced uppercase {XXXXXXXX-XXXX-4XXX-YXXX-XXXXXXXXXXXX} | 122 random bits | COM components, Windows Registry, .NET entity IDs |
| Raw 32-Hex (No Hyphens) | 32 consecutive hex chars (xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx) | 128-bit compact | Mongo ObjectId alternates, URL paths, compact payload keys |
| Collision Probability | 1 in 2.71 × 10¹⁸ (after generating 1 billion UUIDs) | Near-zero risk | High-concurrency batch seeding without coordinate locks |
Frequently Asked Questions
Clear answers about using this tool and automating workflows with RunMacro.
What is the probability of two UUID v4 values colliding?
The probability of a duplicate UUID v4 is approximately 1 in 2.71 quintillion (2.71 × 10¹⁸). Generating 1 billion UUIDs per second for 100 consecutive years would still carry a virtually negligible risk of collision.
What is the difference between UUID and GUID?
A UUID (Universally Unique Identifier) is defined by the standard RFC 4122, while a GUID (Globally Unique Identifier) is Microsoft's implementation of the 128-bit identifier standard. Mechanically and mathematically, UUID v4 and GUID are identical.
Can I generate UUIDs without hyphens?
Yes. Enable the 'Without hyphens (32 chars)' toggle to strip dashes and generate compact 32-character hexadecimal strings suitable for database keys and clean URL tokens.
How does RunMacro automate UUID injection in desktop software?
RunMacro allows you to dynamically populate unique UUIDs and test variables across automated forms, database seeding scripts, and desktop applications without requiring custom code.
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