OpenAI just dropped GPT-5, and this isn't your typical AI upgrade—it's a fundamental shift in how artificial intelligence works. The new model doesn't just spit out answers anymore; it actually thinks through problems, dramatically reducing errors and hallucinations that have plagued previous AI systems.
GPT-5's standout feature is its built-in reasoning capability. Unlike previous models that generate responses instantly, GPT-5 can pause, think through complex problems, and deliver more accurate answers.
In testing, it produced 80% fewer factual errors than OpenAI's previous reasoning model, o3, when given time to think through responses.
The system works through a "unified approach" that automatically decides when to respond quickly for simple questions versus when to engage deeper reasoning for complex tasks. A smart router analyzes your prompt and chooses the appropriate response mode—no manual switching required.
Performance Leaps Across the Board
The improvements are substantial across key areas. In coding, GPT-5 achieved 74.9% success on SWE-bench Verified (a challenging software engineering benchmark) and can create complete, responsive websites from a single prompt. For health queries, it scored 46.2% on HealthBench Hard, significantly outperforming previous models while being less likely to provide potentially harmful medical advice.
Math performance hit new heights with 94.6% accuracy on AIME 2025 problems—competitive math challenges that typically stump most humans. The model also shows dramatic improvements in visual understanding and multimodal reasoning.
Real-World Impact: Less BS, More Accuracy
Perhaps most importantly for everyday users, GPT-5 addresses the "hallucination problem" that made previous AI models unreliable for factual information. The new model is 45% less likely to make up facts compared to GPT-4o, and when reasoning is engaged, that number jumps to 80% fewer errors.
OpenAI also tackled the "sycophancy" issue—where AI models would agree with users even when they were wrong. GPT-5 cuts sycophantic responses by more than half, making it more honest about its limitations and more likely to provide constructive pushback when appropriate.
Getting Your Hands on GPT-5
GPT-5 is rolling out now as the new default in ChatGPT, replacing GPT-4o for all users. Free users get limited access, while Plus subscribers ($20/month) get significantly more usage. Pro subscribers ($200/month) get unlimited access plus GPT-5 Pro, which uses extended reasoning for the most challenging tasks.
Microsoft is simultaneously integrating GPT-5 across its ecosystem, including Office 365 Copilot, GitHub Copilot, and Azure AI services, making this the most widespread AI model launch in history.