🎲 UUID Generator CLI

A powerful and beautiful command-line tool for generating UUIDs with extensive formatting options and multiple UUID versions support.

✨ Features

• 🎯 Multiple UUID Versions - v1, v3, v4, v5, NIL, and custom formats
• 🎨 Flexible Formatting - Uppercase, no dashes, braces, prefix/suffix
• 📋 Clipboard Support - Automatically copy generated UUIDs
• 💾 Multiple Export Formats - TXT, JSON, CSV, SQL
• ⚡ Bulk Generation - Generate thousands of UUIDs efficiently
• ✅ UUID Validation - Validate and analyze existing UUIDs
• 🌈 Beautiful CLI Output - Colorful, formatted terminal display
• 🔧 Customizable - Create UUIDs with custom templates

📦 Installation

Prerequisites

• Node.js 16.x or higher
• npm or yarn

Local Installation

Global Installation

npm install -g uuid-gen-cli

🚀 Quick Start

# Generate a single UUID v4 (most common)
uuid-gen v4

# Generate 10 UUIDs
uuid-gen v4 -c 10

# Generate and copy to clipboard
uuid-gen v4 --copy

# Generate 5 uppercase UUIDs without dashes
uuid-gen v4 -c 5 --uppercase --no-dashes

# Validate a UUID
uuid-gen validate 550e8400-e29b-41d4-a716-446655440000

📖 Usage

Basic Syntax

uuid-gen <command> [options]

Available Commands

| Command | Description | |---------|-------------| | v1 | Generate time-based UUID (version 1) | | v4 | Generate random UUID (version 4) - Most common | | v3 <name> | Generate MD5 hash-based UUID (version 3) | | v5 <name> | Generate SHA-1 hash-based UUID (version 5) | | nil | Generate NIL UUID (all zeros) | | custom | Generate custom format UUID | | bulk | Generate bulk UUIDs efficiently | | validate <uuid> | Validate and analyze a UUID |

💡 Examples

UUID v4 (Random) - Most Common

# Single UUID
 uuid-gen node index.js v4 -c 10
{ count: '10', dashes: true, format: 'txt' }

╔══════════════════════════════════════════════════════════╗
║ UUID v4 (Random)                                         ║
╠══════════════════════════════════════════════════════════╣
║ Count: 10                                                ║
║ Format: lowercase                                        ║
╚══════════════════════════════════════════════════════════╝

  01. b48e69ad-172e-4115-9c17-6050950d4d2d
  02. 7804c62a-ecd7-4651-a8b6-b8775b9c1bc3
  03. f8fa281d-948c-4328-9f37-8b31182a12d2
  04. 03179ba0-5b2c-4487-8d19-49fa750d98db
  05. 538b371b-c441-4aea-81a4-827253abe6b5
  06. 089c8898-e8bd-4b25-8b78-2ab24a937572
  07. 41cdee5c-1351-4e9c-8685-9339174ae062
  08. a626c539-acd4-42f5-9a34-1881f59bd8e2
  09. 2dc321f5-decb-4481-9ac3-13814f9340ab
  10. 229f7e87-a473-4ee6-b5f7-b4b14fa01358

# Generate 10 UUIDs
uuid-gen v4 -c 10

# Generate 5 uppercase UUIDs
uuid-gen v4 -c 5 --uppercase

# Generate without dashes
uuid-gen v4 -c 3 --no-dashes

# Generate with braces
uuid-gen v4 -c 3 --braces
# Output: {7c9e6679-7425-40de-944b-e07fc1f90ae7}

# Generate with prefix and suffix
uuid-gen v4 -c 5 --prefix "USER-" --suffix "-ID"
# Output: USER-7c9e6679-7425-40de-944b-e07fc1f90ae7-ID

# Copy to clipboard
uuid-gen v4 --copy

UUID v1 (Time-based)

# Generate time-based UUID
uuid-gen v1

# Generate 5 time-based UUIDs
uuid-gen v1 -c 5

# Time-based with formatting
uuid-gen v1 -c 3 --uppercase --braces

UUID v5 (Hash-based with Name)

# Generate UUID from domain name
uuid-gen v5 "example.com"

# Using different namespaces
uuid-gen v5 "example.com" --namespace dns
uuid-gen v5 "https://example.com" --namespace url
uuid-gen v5 "mydata" --namespace oid

# Generate multiple with incrementing names
uuid-gen v5 "user" -c 5
# Output: user-0, user-1, user-2, user-3, user-4

# Custom namespace UUID
uuid-gen v5 "mydata" --namespace "6ba7b810-9dad-11d1-80b4-00c04fd430c8"

UUID v3 (MD5 Hash-based)

# Similar to v5 but uses MD5 instead of SHA-1
uuid-gen v3 "example.com" --namespace dns
uuid-gen v3 "mydata" -c 5

NIL UUID

# Generate NIL UUID (all zeros)
uuid-gen nil

# Output: 00000000-0000-0000-0000-000000000000

Custom Format

# Custom format template (x = random hex, y = variant bits)
uuid-gen custom --format "xxxx-xxxx-xxxx" -c 5

# Custom length
uuid-gen custom --format "xxxxxxxx" -c 3

# Complex custom format
uuid-gen custom --format "xxxx-yyyy-xxxx-yyyy" -c 5 --uppercase

Bulk Generation

# Generate 10,000 UUIDs
uuid-gen bulk -c 10000 -o uuids.txt

# Generate 5,000 uppercase UUIDs without dashes
uuid-gen bulk -c 5000 --uppercase --no-dashes -o uuids.txt

# Generate bulk as JSON
uuid-gen bulk -c 1000 -o uuids.json --format json

# Generate bulk as CSV
uuid-gen bulk -c 2000 -o uuids.csv --format csv

# Generate bulk as SQL
uuid-gen bulk -c 500 -o uuids.sql --format sql

Save to File

# Save as text file
uuid-gen v4 -c 100 --file uuids.txt

# Save as JSON
uuid-gen v4 -c 50 --file uuids.json --format json

# Save as CSV
uuid-gen v4 -c 200 --file uuids.csv --format csv

# Save as SQL values
uuid-gen v4 -c 100 --file uuids.sql --format sql

Validate UUID

# Validate and analyze a UUID
uuid-gen validate 550e8400-e29b-41d4-a716-446655440000

# Output:
# ╔══════════════════════════════════════════════════════════╗
# ║ UUID Analysis                                            ║
# ╠══════════════════════════════════════════════════════════╣
# ║ UUID: 550e8400-e29b-41d4-a716-446655440000              ║
# ║ Valid: ✓ YES                                            ║
# ║ Version: 4                                              ║
# ║ Variant: 1010                                           ║
# ║ Type: Random                                            ║
# ╚══════════════════════════════════════════════════════════╝

# Validate invalid UUID
uuid-gen validate "not-a-uuid"

🎛️ Options

Common Options (Available for Most Commands)

| Option | Short | Description | Default | |--------|-------|-------------|---------| | --count <n> | -c | Number of UUIDs to generate | 1 | | --uppercase | -u | Output in uppercase | false | | --no-dashes | -n | Remove dashes from output | false | | --braces | -b | Wrap UUID in braces {} | false | | --prefix <text> | -p | Add prefix to each UUID | - | | --suffix <text> | -s | Add suffix to each UUID | - | | --file <path> | -f | Save to file | - | | --format <type> | | File format (txt, json, csv, sql) | txt | | --copy | | Copy first UUID to clipboard | false |

Version-Specific Options

v3 and v5 Options

| Option | Description | Default | |--------|-------------|---------| | --namespace <ns> | Namespace (dns, url, oid, x500, or UUID) | dns |

Bulk Options

| Option | Description | |--------|-------------| | --version <v> | UUID version (v1, v4, random) | | --output <path> | Output file path (required) |

Custom Options

| Option | Description | Default | |--------|-------------|---------| | --format <template> | Custom format template | xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx |

📁 File Formats

Text Format (default)

7c9e6679-7425-40de-944b-e07fc1f90ae7
3d813cbb-47fb-42eb-89e3-5b6d9d2b1f85
9c5e1f0a-8d4c-4a7e-9f3b-2e1d6c8b9a0f

JSON Format

[
  "7c9e6679-7425-40de-944b-e07fc1f90ae7",
  "3d813cbb-47fb-42eb-89e3-5b6d9d2b1f85",
  "9c5e1f0a-8d4c-4a7e-9f3b-2e1d6c8b9a0f"
]

CSV Format

uuid
7c9e6679-7425-40de-944b-e07fc1f90ae7
3d813cbb-47fb-42eb-89e3-5b6d9d2b1f85
9c5e1f0a-8d4c-4a7e-9f3b-2e1d6c8b9a0f

SQL Format

'7c9e6679-7425-40de-944b-e07fc1f90ae7',
'3d813cbb-47fb-42eb-89e3-5b6d9d2b1f85',
'9c5e1f0a-8d4c-4a7e-9f3b-2e1d6c8b9a0f'

🔍 UUID Versions Explained

UUID v1 (Time-based)

• Generated from current timestamp and MAC address
• Guaranteed to be unique (given same machine)
• Reveals timestamp and location information
• Use case: When you need time-ordered UUIDs

UUID v4 (Random)

• Generated from random numbers
• Most commonly used version
• No information leakage
• Use case: General purpose, most applications

UUID v3 (MD5 Hash)

• Generated from namespace and name using MD5
• Deterministic (same input = same UUID)
• Use case: When you need reproducible UUIDs

UUID v5 (SHA-1 Hash)

• Generated from namespace and name using SHA-1
• Deterministic (same input = same UUID)
• More secure than v3
• Use case: When you need reproducible UUIDs with better security

NIL UUID

• All zeros: 00000000-0000-0000-0000-000000000000
• Use case: Placeholder, default value

🎨 Output Examples

Standard Output

╔══════════════════════════════════════════════════════════╗
║ UUID v4 (Random)                                         ║
╠══════════════════════════════════════════════════════════╣
║ Count: 5                                                 ║
║ Format: lowercase                                        ║
╚══════════════════════════════════════════════════════════╝

  01. 7c9e6679-7425-40de-944b-e07fc1f90ae7
  02. 3d813cbb-47fb-42eb-89e3-5b6d9d2b1f85
  03. 9c5e1f0a-8d4c-4a7e-9f3b-2e1d6c8b9a0f
  04. 2f8b3a1c-5d9e-4f7a-8c6b-1e4d7a9f3b2c
  05. 8a7f6e5d-4c3b-4a29-9f8e-7d6c5b4a3f2e

Bulk Generation Progress

🚀 Generating bulk UUIDs...
  Progress: 1000/10000
  Progress: 2000/10000
  ...
  Progress: 10000/10000
✓ Saved 10000 UUIDs to: uuids.txt
✓ Generated 10000 UUIDs

🔧 Advanced Usage

Combining Multiple Options

# Generate 100 uppercase UUIDs with braces, save as JSON
uuid-gen v4 -c 100 --uppercase --braces --file output.json --format json

# Generate UUIDs with custom prefix/suffix and save
uuid-gen v4 -c 50 --prefix "ID_" --suffix "_END" --file ids.txt

# Generate bulk with all formatting
uuid-gen bulk -c 5000 --uppercase --no-dashes -o output.csv --format csv

Using in Scripts

#!/bin/bash

# Generate UUID and use in script
UUID=$(uuid-gen v4 | grep -o '[a-f0-9-]\{36\}')
echo "Generated UUID: $UUID"

# Create 100 user IDs
uuid-gen v4 -c 100 --prefix "USER_" --file user_ids.txt

# Generate database insert statements
uuid-gen v4 -c 1000 --file uuids.sql --format sql

Integration Examples

Shell Script

# Generate and use UUID
NEW_ID=$(uuid-gen v4 --copy)
echo "Created new ID: $NEW_ID"

Python Integration

import subprocess

# Generate UUID using CLI
result = subprocess.run(['uuid-gen', 'v4'], capture_output=True, text=True)
uuid = result.stdout.strip().split('\n')[-1].strip()
print(f"Generated UUID: {uuid}")

Node.js Integration

const { execSync } = require('child_process');

// Generate UUID
const uuid = execSync('uuid-gen v4').toString().trim().split('\n').pop();
console.log(`Generated UUID: ${uuid}`);

🐛 Troubleshooting

Issue: "Cannot copy to clipboard"

Solution: Clipboardy requires additional dependencies on Linux

sudo apt-get install xclip  # Ubuntu/Debian

📊 Performance

• Single UUID: ~1ms
• 100 UUIDs: ~5ms
• 1,000 UUIDs: ~50ms
• 10,000 UUIDs: ~500ms
• 100,000 UUIDs: ~5s

Bulk generation uses batching for optimal performance.

📝 License

This project is licensed under the MIT License.

👤 Author

• Mohan Chinnappan

📚 Resources

• RFC 4122 - UUID Specification
• UUID Best Practices
• When to use which UUID version

🔮 Future Enhancements

• [ ] UUID v6 and v7 support (draft specification)
• [ ] Interactive mode with prompts
• [ ] UUID comparison tool
• [ ] Batch validation from file
• [ ] Web interface
• [ ] REST API mode
• [ ] Database integration helpers
• [ ] More output formats (XML, YAML)

Made with ❤️ for the UUID community