You don’t need to spend thousands on certifications to start a career in cybersecurity. In 2025, there are dozens of free security courses online that cover everything from basic cyber hygiene to advanced ethical hacking. The challenge is figuring out which ones are worth your time.
To save you hours of searching, here’s a curated list of the 12 best free cybersecurity courses in 2025 that are beginner-friendly, industry-relevant, and trusted by professionals.
1. Google Cybersecurity Professional Certificate (Audit Mode)
Google’s entry-level course on Coursera introduces you to security concepts, tools, and frameworks. You can audit the content for free.
Pros:
- Beginner-friendly, no prior experience needed
- Hands-on labs and exercises
Cons:
- Certificate requires payment
- Some labs require extra setup
Visit Google Cybersecurity Course
2. Cisco Networking Academy – Introduction to Cybersecurity
A short but effective course explaining key security concepts, cyber threats, and basic defense strategies.
Pros:
- Recognized Cisco resource
- Covers networking + security fundamentals
Cons:
- Introductory only, not in-depth
- Limited interactive labs
Visit Cisco Networking Academy
3. IBM Cybersecurity Analyst (Audit on Coursera)
Covers network security, endpoint protection, incident response, and SIEM tools. Audit mode is free.
Pros:
- Practical real-world examples
- Industry-recognized IBM brand
Cons:
- Certificate costs extra
- Can feel corporate-heavy
Visit IBM Cybersecurity Analyst
4. Harvard CS50’s Computer Science for Cybersecurity
Part of the world-famous CS50 series, this course covers programming foundations with a focus on security.
Pros:
- Ivy League teaching quality
- Builds strong foundations
Cons:
- Requires more time commitment
- Some sections may feel advanced
5. Open Security Training – Intro to x86 Assembly & Exploits
Perfect for those interested in reverse engineering and exploit development.
Pros:
- Deep technical knowledge
- Free, community-driven resource
Cons:
- Requires prior programming skills
- Can be very technical for beginners
6. FutureLearn – Introduction to Cyber Security
Created by the UK’s Open University, this course is a great primer for beginners.
Pros:
- Easy to follow, clear teaching
- Covers practical everyday risks
Cons:
- Limited depth on advanced topics
- Time-limited free access unless upgraded
Visit FutureLearn Cybersecurity
7. Stanford Online – Computer and Network Security Lectures
Free recorded lectures from Stanford professors on cryptography, networking, and security principles.
Pros:
- Academic-level depth
- Trusted source
Cons:
- Less structured than typical online courses
- Requires motivation to self-study
8. Cybrary – Free Cybersecurity Courses
Cybrary offers a wide range of free modules on penetration testing, security operations, and compliance.
Pros:
- Flexible, pick topics of interest
- Active cybersecurity community
Cons:
- Some premium features locked
- Interface can be overwhelming
9. Microsoft Learn – Security, Compliance, and Identity Fundamentals
Ideal for those working with Microsoft cloud services like Azure.
Pros:
- Cloud-focused, practical skills
- Free learning paths from Microsoft
Cons:
- Very Microsoft-specific
- Less relevant if you’re not in Azure ecosystem
10. OWASP Security Shepherd
A gamified platform to learn application security and secure coding practices.
Pros:
- Interactive, hands-on practice
- Teaches OWASP Top 10 vulnerabilities
Cons:
- Requires setup for some modules
- Not ideal for absolute beginners
11. EC-Council – Essentials Series (Free)
Covers network defense, ethical hacking basics, and digital forensics.
Pros:
- Taught by EC-Council experts
- Industry-recognized name
Cons:
- Marketing-heavy, pushes toward paid certs
- Surface-level coverage
12. Udemy Free Cybersecurity Courses
Udemy often has rotating free cybersecurity courses on ethical hacking, Kali Linux, and cloud security.
Pros:
- Accessible, beginner-friendly
- Huge variety of topics
Cons:
- Quality varies by instructor
- Limited support for free courses
Key Takeaways
- Google Cybersecurity Certificate (audit mode) is the best structured beginner path.
- Cisco Networking Academy and FutureLearn are great for absolute beginners.
- IBM Cybersecurity Analyst and EC-Council Essentials cover professional-level skills.
- OWASP Security Shepherd and Open Security Training are excellent for hands-on hacking practice.
- Stanford Online and Harvard CS50 offer university-level depth for free.
- Cybrary and Udemy provide flexibility to explore multiple topics.
- Microsoft Learn is essential for those working in cloud and enterprise environments.
Whether you’re starting out or upskilling, these free security courses in 2025 can help you build practical, job-ready cybersecurity skills without spending a cent.