Here are some of the best free online certifications in 2025 to boost your resume:

1. Generative AI for Beginners by Microsoft - Introduction to AI models like ChatGPT, great for staying ahead in tech.
2. Prompt Engineering for ChatGPT by Vanderbilt University (Coursera) - Learn to optimize AI tool use, a sought skill.
3. Master Microsoft Office 365 and Power Platform by Microsoft (Coursera) - Enhances productivity and automation skills.
4. freeCodeCamp Certifications - Includes Responsive Web Design, JavaScript Algorithms, Front End Libraries, etc.
5. Google Certifications - Includes Google Analytics, Google Ads, and Fundamentals of Digital Marketing.
6. Cybersecurity Certificates - Cisco Networking Academy and others offer beginner to advanced courses.
7. IBM Data Science Professional Certificate on Coursera - Focuses on machine learning, data analysis, and tools.
8. CS50's Introduction to Computer Science by Harvard (edX) - Entry-level coding and computer science fundamentals.
9. Google IT Automation with Python Professional Certificate - For practical IT and automation skills.
10. Alison Platform Certificates - Free diplomas and certificates on business, IT, project management, and more.

These courses and certifications are highly valued for demonstrating updated skills across tech, digital marketing, data science, cybersecurity, and productivity tools. They are widely accessible, self-paced, and offer recognized certificates to help enhance any resume or job application in 2025.