UUID Generator Bulk: Generate Hundreds of UUIDs Instantly Online

Seeding a database, populating test fixtures, creating sample data for a demo — all of these need UUIDs in quantity. A bulk UUID generator lets you produce hundreds or thousands of unique IDs in seconds and export them in whatever format you need.

Generate UUIDs in Bulk →

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UUID Versions: Which to Use

Version	Algorithm	Best For
v1	Timestamp + MAC address	When time-ordering matters, audit logs
v4	Random	General purpose — default choice
v5	SHA-1 + namespace	Reproducible IDs from known input
v7	Unix timestamp + random	Database primary keys, sortable IDs

UUID v4 (Random) — The Default

550e8400-e29b-41d4-a716-446655440000
f47ac10b-58cc-4372-a567-0e02b2c3d479

128 bits with 122 random bits. Collision probability is astronomically low (requires generating 103 trillion UUIDs to reach 1% collision probability). Use this for most cases.

UUID v7 (Sortable) — The Modern Choice

018e3c0a-4e5b-7000-8000-000000000001
018e3c0a-4e5c-7000-8000-000000000002

v7 encodes Unix timestamp in the first 48 bits, making UUIDs sortable chronologically. This matters for:

• Database indexes (b-tree indexes stay efficient when IDs are monotonically increasing)
• Log correlation
• Event sourcing
• Any system where "creation order" should be visible from the ID

If you're choosing a UUID version for new database primary keys, choose v7.

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Bulk Generation Use Cases

Database Seeding

Creating test data for a relational database:

INSERT INTO users (id, name, email) VALUES
  ('550e8400-e29b-41d4-a716-446655440000', 'Alice', '[e-mail]'),
  ('f47ac10b-58cc-4372-a567-0e02b2c3d479', 'Bob', '[e-mail]'),
  -- ... 98 more rows

Generate 100 UUIDs, download as CSV, import to SQL.

Test Fixtures

[
  { "id": "550e8400-e29b-41d4-a716-446655440000", "type": "order" },
  { "id": "f47ac10b-58cc-4372-a567-0e02b2c3d479", "type": "order" },
  { "id": "7c9e6679-7425-40de-944b-e07fc1f90ae7", "type": "order" }
]

API Mock Data

Building a mock API that returns consistent UUIDs for demo purposes.

Load Testing

Generate unique IDs for 10,000 synthetic users to load test your system without polluting production data.

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Generating UUIDs in Code

JavaScript / Node.js

// Built-in (Node.js 14.17+, browsers)
import { randomUUID } from 'crypto';
const id = randomUUID(); // v4

// Generate bulk
const uuids = Array.from({ length: 100 }, () => randomUUID());

// uuid package (all versions)
import { v4 as uuidv4, v7 as uuidv7 } from 'uuid';

const v4id = uuidv4();
const v7id = uuidv7();

// Bulk v7 (sortable, good for DB)
const sortableIds = Array.from({ length: 1000 }, () => uuidv7());

Python

import uuid

# Single v4
uid = uuid.uuid4()
print(str(uid))  # "550e8400-e29b-41d4-a716-446655440000"

# Bulk generation
uuids = [str(uuid.uuid4()) for _ in range(100)]

# Namespaced v5 (reproducible)
namespace = uuid.NAMESPACE_URL
uid5 = uuid.uuid5(namespace, "https://example.com/users/alice")

# Export to CSV
import csv
with open('uuids.csv', 'w') as f:
    writer = csv.writer(f)
    for uid in uuids:
        writer.writerow([uid])

Go

import "github.com/google/uuid"

// Single v4
id := uuid.New()
fmt.Println(id.String())

// Bulk v4
ids := make([]string, 1000)
for i := range ids {
    ids[i] = uuid.New().String()
}

// v7 (sortable)
id7, err := uuid.NewV7()

SQL (PostgreSQL)

-- Generate UUIDs in SQL
SELECT gen_random_uuid() FROM generate_series(1, 100);

-- Insert with UUIDs
INSERT INTO items (id, name)
SELECT gen_random_uuid(), 'Item ' || n
FROM generate_series(1, 1000) AS s(n);

-- UUID primary key column
CREATE TABLE products (
  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
  name TEXT NOT NULL
);

Bash

# Single UUID (Linux)
cat /proc/sys/kernel/random/uuid

# Bulk with uuidgen
for i in $(seq 1 100); do uuidgen; done

# Export to file
for i in $(seq 1 1000); do uuidgen; done > uuids.txt

# macOS
uuidgen | tr '[:upper:]' '[:lower:]'

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UUID Format Variants

Standard UUID: 550e8400-e29b-41d4-a716-446655440000

Applications sometimes use non-standard formats:

Format	Example	Use case
Standard	550e8400-e29b-41d4-a716-446655440000	Most systems
No hyphens	550e8400e29b41d4a716446655440000	Compact storage
Uppercase	550E8400-E29B-41D4-A716-446655440000	Some legacy systems
Braces	{550e8400-e29b-41d4-a716-446655440000}	Windows/COM
URN	urn:uuid:550e8400-e29b-41d4-a716-446655440000	Semantic web

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UUID vs ULID vs CUID

ID Type	Sortable	URL-safe	Length	Notes
UUID v4	No	With encoding	36 chars	Industry standard
UUID v7	Yes	With encoding	36 chars	Best for databases
ULID	Yes	Yes	26 chars	Compact, readable
CUID2	Approximately	Yes	Configurable	Anti-fingerprinting
NanoID	No	Yes	Configurable	Short, URL-safe

For new projects in 2026:

• General use: UUID v4 (universal support)
• Database PKs: UUID v7 or ULID
• URLs: NanoID or CUID2

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Export Formats for Bulk UUIDs

A good bulk generator exports in multiple formats:

Plain text (one per line)

550e8400-e29b-41d4-a716-446655440000
f47ac10b-58cc-4372-a567-0e02b2c3d479
7c9e6679-7425-40de-944b-e07fc1f90ae7

CSV (with index)

index,uuid
1,550e8400-e29b-41d4-a716-446655440000
2,f47ac10b-58cc-4372-a567-0e02b2c3d479

JSON array

[
  "550e8400-e29b-41d4-a716-446655440000",
  "f47ac10b-58cc-4372-a567-0e02b2c3d479"
]

SQL INSERT

INSERT INTO table_name (id) VALUES
  ('550e8400-e29b-41d4-a716-446655440000'),
  ('f47ac10b-58cc-4372-a567-0e02b2c3d479');

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Related Tools

• UUID Generator — single and bulk UUID generation
• JSON Formatter — format UUID arrays in JSON
• API Request Builder — test endpoints with generated UUIDs

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Conclusion

Bulk UUID generation is a routine task in database seeding, testing, and mock data creation. An online bulk UUID generator handles it in seconds with no code, in whatever format your workflow needs.

Generate Bulk UUIDs Online →

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