GPT-5 in real-world use: is the new AI model worth it for web development & SEO?

On August 7, 2025, OpenAI released GPT-5 – promoted as the biggest leap since GPT-4. But is that really true? In this practical test, I show how GPT-5 performs specifically in web development and search engine optimization – directly from my daily work in Augsburg.

GPT-5 vs GPT-4: noticeable improvements

After the first tests, one thing is clear: GPT-5 is faster and thinks much more structured. For complex tasks such as PHP debugging, developing complete SEO strategies or creating structured data, it produces fewer confusing answers and more genuinely useful results.

GPT-5 context window: more room for large projects

The new context window is a real game changer. While GPT-4o handled around 128,000 tokens, GPT-5 processes content in the millions. That means complete project briefings, long chat histories or extensive code files remain available without constant re-uploading.

Multimodality in GPT-5

Text, images and audio in a single model. Especially useful for image descriptions (accessibility), extracting information from screenshots or performing SEO analysis based on layouts.

Personalization: nice, but not essential

Profiles, Gmail integration, Google Calendar – useful features, but for daily web development and SEO work, consistency and reliability matter more.

The downside: hallucinations still exist

GPT-5 is not flawless. Incorrect facts occur less often, but they still happen. Results should always be checked for professional or client work.

Conclusion: GPT-5 is a strong upgrade

GPT-4 is still sufficient for simple tasks. But anyone working on complex web projects, serious SEO or large data sets will benefit significantly from GPT-5.