Developer Lab · Perl

Generate UUID in Perl

UUID generation in Perl using the Data::UUID CPAN module - battle-tested and widely deployed.

Implementation Code

Production Ready

perl

use strict;
use warnings;
use Data::UUID;

my $ug = Data::UUID->new;

# Generate a time-based UUID string
my $uuid = $ug->create_str;
print "$uuid\n";

# Generate multiple
for (1..5) {
    print $ug->create_str, "\n";
}

Explanation

Data::UUID is the standard CPAN module for UUID generation in Perl. create_str() returns a UUID as a formatted string (e.g. 550e8400-e29b-41d4-a716-446655440000). Use create() for a binary representation.

Output Example

7f3c2a1b-9d4e-4f8a-b5c6-3e2d1f0a9b8c

Best Practices, Performance, and Security

Best practices

✓

Reuse the Data::UUID object across calls rather than creating a new instance each time. For web apps, consider UUID::Tiny as a pure-Perl alternative with no XS dependency.

Performance

Good. Data::UUID is XS-based (C extension) so it's fast. Suitable for high-volume ID generation in Perl services.

Security

Uses OS-level entropy sources. Suitable for non-security-critical identifiers. For session tokens, prefer a dedicated CSPRNG source.

Installation

Data::UUID (CPAN)

bash

cpan Data::UUID

Or via system package manager: apt install libdata-uuid-perl

Frequently Asked Questions

How do I generate a UUID in Perl?

Use a CPAN module such as Data::UUID or UUID::Tiny. With UUID::Tiny, import create_uuid_as_string and call create_uuid_as_string(UUID_V4) for a random v4 UUID. Data::UUID is also widely deployed and battle-tested.

Is Data::UUID->create_str() cryptographically secure?

No. Data::UUID->create_str() produces a time-based (v1-style) UUID derived from the timestamp and host, not output from a CSPRNG. For security-sensitive identifiers such as session tokens or API keys, use UUID::Tiny's create_uuid_as_string(UUID_V4), which draws on the OS secure random source.

What is the difference between UUID v4 and v7 in Perl?

UUID v4 (via UUID::Tiny's UUID_V4) is fully random and not sortable. UUID v7 embeds a millisecond timestamp for chronological sorting (RFC 9562). Use v4 for general-purpose IDs; use v7 for database primary keys at scale.

Do I need to install a package for UUID generation in Perl?

A package or library install may be required. See the Installation section for the recommended approach in Perl.

How do I validate a UUID string in Perl?

Use the platform's UUID parse/validation function, or test against the RFC 4122 regex: /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i. Always validate external input at API boundaries.

Should I use UUIDs as database primary keys in Perl applications?

UUIDs work well as primary keys for distributed systems. Prefer native UUID/BINARY(16) column types over VARCHAR(36). For very large tables, consider UUID v7 for better B-tree insert locality.

Can I generate UUIDs in Perl without a network connection?

Yes. UUID generation uses local OS entropy sources and does not require network access. Each call is independent and thread-safe on modern platforms.

What output formats are available in Perl?

The standard hyphenated lowercase string (36 chars) is the default. Most APIs also support 32-char hex (no hyphens) and 16-byte binary formats. Use string format for APIs and binary for database storage.

What RFC standards apply to Perl UUID generation?

Version 4 UUIDs follow RFC 4122. UUID v7 follows RFC 9562 (May 2024). Ensure your chosen method produces compliant version and variant bits.

When should I avoid UUID v1?

Avoid UUID v1 in security-sensitive contexts - it embeds MAC address and timestamp information. Prefer v4 (via UUID::Tiny's UUID_V4) unless you need legacy Cassandra timeuuid compatibility.

Key definitions

UUID: 128-bit universally unique identifier, usually shown as 36 hex characters with hyphens.
CSPRNG: Cryptographically secure pseudo-random number generator - the entropy source behind secure UUID generation.
RFC 4122: IETF standard defining UUID versions 1 through 5. Version 4 is random.
RFC 9562: IETF standard adding UUID versions 6, 7, and 8. Version 7 is time-ordered.