Performance testing helps developers understand how fast a website really is.
Without testing, it is impossible to know where improvements are needed.
Why Performance Testing Matters
Developers often think a website is fast, but real users experience it differently.
Testing shows the real performance of a webpage.
What to Measure
When testing performance, focus on:
- Page load time
- First content shown
- Responsiveness
- Visual stability
Common Performance Testing Tools
Developers use tools such as:
- Browser developer tools
- Online speed testing services
- Website audit tools
Using Browser Developer Tools
Modern browsers include performance testing features.
These tools show loading time, network requests, and rendering behavior.
Testing this page before and after adding lazy loading shows a clear speed improvement.
Performance Testing Workflow
A professional workflow includes:
- Measure current speed
- Identify slow elements
- Apply optimization
- Test again
Testing on Real Devices
Always test on:
- Mobile phones
- Slow networks
- Different browsers
Automated Performance Testing
Large projects often use automated tools to check performance regularly.
This ensures performance does not degrade over time.
Common Performance Testing Mistakes
- Testing only on fast computers
- Ignoring mobile users
- Measuring only once
Performance Testing in Real Projects
Performance testing is required for:
- E-commerce websites
- SaaS applications
- News and content platforms
Why Performance Testing Matters for Jobs
Companies care about speed and reliability.
Developers who can test and optimize performance are highly valued.
Practice Task
Choose a webpage and:
- Test its speed using browser tools
- Identify slow elements
- Apply one optimization and test again
Chapter Summary
In this chapter, you learned how to optimize HTML for performance, reduce load time, connect performance with SEO, and test websites using professional tools.
What You Will Learn Next
In the next chapter, you will learn about HTML project structure and real-world development workflow.