OpenAI claims that ChatGPT-5 is 'smarter,' offers better reasoning, better memory, and a more natural user experience. Let's take a look at how big of an upgrade ChatGPT-5 really is, as compared to ChatGPT-4.

With the release of ChatGPT-5, OpenAI has taken a significant leap beyond the capabilities of its previous flagship, ChatGPT-4. While ChatGPT-4 Turbo introduced faster responses and reduced costs, ChatGPT-5 focuses on deeper intelligence, greater versatility, and more human-like interactions. OpenAI claims that ChatGPT-5 is 'smarter,' offers better reasoning, better memory, and a more natural user experience.

Let's take a look at how big of an upgrade ChatGPT-5 really is, as compared to ChatGPT-4:

1. ChatGPT-5 comes with multimodal understanding

ChatGPT-4 was the first version to experiment with multimodal input, allowing users to upload images and get responses based on what the model 'saw.' ChatGPT-5 builds on this and fully embraces multimodality. It now understands text, images, audio, and video, and can even generate responses based on combinations of these formats. For example, you can upload a chart, ask a question in voice, and receive a text summary that references both.

This shift suggests that ChatGPT-5 is evolving into a unified assistant that understands multiple forms of communication at once, making it far more useful for professional, academic, or creative work.

2. ChatGPT-5 offers more smarter and context-aware responses

ChatGPT-4 already offered strong general intelligence, but ChatGPT-5 dramatically improves the model’s ability to think through complex problems. One of the most notable upgrades is reasoning depth. ChatGPT-5 can follow long chains of logic more accurately, solve more advanced coding and math tasks, and explain its thought process more clearly.

Another major enhancement is its context window. While ChatGPT-4 could remember and process around 128,000 tokens in its most advanced version, ChatGPT-5 supports up to a million tokens, meaning it is likely to handle entire books, in-depth technical documents, or prolonged conversations without forgetting earlier parts of the discussion. This makes ChatGPT-5 feel far more attentive and useful in long-form interactions.

3. ChatGPT-5 improves on integration of tools and autonomy

ChatGPT-4 introduced features like browsing and code interpretation in the Pro version, but ChatGPT-5 takes tool use to a new level. It can now connect more smoothly with external tools and services, including Gmail, Google Calendar, and productivity apps. These integrations allow ChatGPT-5 to schedule meetings, draft emails, summarise inboxes, or organize your day, without needing constant direction.

4. ChatGPT-5 offers better personalisation and memory

ChatGPT-4 had some early personalisation features, especially in the Pro version, but ChatGPT-5 introduces a much stronger memory system. The model can now remember key information about users across sessions—such as your name, preferences, tone of communication, or frequent tasks—and apply that knowledge to offer more tailored responses.

Beyond just memory, GPT-5 also lets users customise their chat experience more actively. You can choose different 'personalities' or communication styles, adjust how formal or concise the assistant should be, and even give it long-term instructions.

5. ChatGPT-5 reduces hallucinations, improves safety

One of the common issues with ChatGPT-4 was 'hallucinations'. The model would sometimes make up facts, dates, or quotes. ChatGPT-5 addresses this more seriously. OpenAI trained the model with a focus on truthfulness and transparency, and early tests show it is better at admitting when it doesn’t know something or when it’s guessing.

Additionally, ChatGPT-5 underwent over 5,000 hours of safety testing before launch. Its responses are now filtered using updated 'safe completion' systems that aim to reduce harmful, misleading, or offensive content.

6. ChatGPT-5 API and developer upgrades

For developers, ChatGPT-5 brings even more flexibility than ChatGPT-4. OpenAI now offers ChatGPT-5 in multiple sizes (like GPT-5-mini and GPT-5-nano) for different levels of power, cost, and speed. Developers can control how verbose, fast, or detailed the responses are by adjusting new parameters like verbosity and reasoning_effort.