UUIDs provide collision-resistant identifiers for distributed systems.
UUID versions
- v1: Timestamp-based (reveals MAC address and creation time).
- v4: Random (most common, cryptographically random).
- v5: Name-based with SHA-1 hashing (deterministic).
- v7: New timestamp-based with improved sorting (RFC draft).
Format
- 8-4-4-4-12 hexadecimal digits: 550e8400-e29b-41d4-a716-446655440000.
Use cases
- Database primary keys in distributed systems.
- Session identifiers and API tokens.
- File and document naming.
- Correlation IDs in microservices.
Security considerations
- UUIDv1 leaks MAC address and timestamp.
- Prefer UUIDv4 for security-sensitive applications.
- Not suitable as secrets or passwords.
Related Articles
View all articlesIncident Management Tools: The Complete Guide for 2026
From on-call scheduling to status pages to postmortems — a comprehensive guide to the tools that power modern incident management, with honest comparisons and pricing.
Read article →Best Atlassian Statuspage Alternatives: Status Page Tools Compared
Atlassian Statuspage is the default choice for hosted status pages, but pricing adds up fast. We compare the best alternatives for teams of every size.
Read article →Best PagerDuty Alternatives in 2026: Features, Pricing, and Who They're For
PagerDuty is the market leader in on-call management, but it's not the only option. We compare the best alternatives — from budget-friendly to enterprise-grade.
Read article →PagerDuty vs Opsgenie: Which On-Call Platform Is Right for Your Team?
A detailed comparison of PagerDuty and Opsgenie — pricing, features, escalation policies, integrations, and which teams each serves best.
Read article →Explore More Development
View all termsAPI (Application Programming Interface)
A set of rules and protocols that allows different software applications to communicate and exchange data.
Read more →Cron Expression
A time-based job scheduling syntax using five or six fields to specify when tasks should run.
Read more →DevOps
A set of practices combining software development (Dev) and IT operations (Ops) to shorten development cycles and deliver high-quality software continuously.
Read more →Diff Algorithm
A computational method for comparing two sets of data and identifying differences between them.
Read more →GitOps
An operational framework that uses Git repositories as the single source of truth for declarative infrastructure and application configurations.
Read more →JSON (JavaScript Object Notation)
A lightweight data interchange format using human-readable text to represent structured data.
Read more →