When OpenAI pulled the sheet off GPT-5, it wasn’t shy about saying this was its most capable model yet. The pitch was that it included everything you loved about the past iterations, plus much more, and all in one seamless form. The result is supposed to be able to understand, create, reason, and switch effortlessly between giving quick answers and writing deep, thoughtful explanations. GPT-5 can process text, images, audio, and video in the same conversation, remember more than you probably do, and adjust its style and personality on the fly. And you’d better like it because it is not only the default model for ChatGPT, it’s the only one accessible for those without an Enterprise subscription.
Gemini 2.5 Flash is the default for Google’s rival AI chatbot. As the name suggests, it’s built for speed, but that doesn’t mean it lacks some power. It’s multimodal and can handle large tasks, but is tuned for near-instant responses and high efficiency. Despite that, I questioned how much of a difference GPT-5’s power would make to the average AI chatbot user, and decided to give the two of them a few tests to see what they came up with.
Party time
My child is too young for a fancy party, but I can easily imagine wanting to make a seemingly elaborate party for him and his friends that doesn’t actually require a party planner. So I asked the two AI chatbots to “Plan a budget-friendly but magical dinosaur-themed birthday party for a seven-year-old, including activities, food, and decorations.”
GPT-5 came back with a complex, detailed plan broken down into small steps that even I could follow. It proposed a “fossil dig” sandbox with little brushes, green streamers twisted into jungle vines, cardboard caves for “dinosaur hide and seek,” and a volcano cake that actually bubbled over before being sliced. It gave a timeline for setup, recommended playing a jungle-sound playlist in the background, and suggested printing “junior paleontologist” badges for the kids.
Gemini Flash’s version was shorter and a little cleaner, but lacked a lot of the extra details. It listed activities like a fossil dig, trivia, and a coloring station, as well as food and decor ideas. Though it didn’t have as much detail in the initial response, it did say to ask about any of the elements for more information and guidance. If you were juggling shopping, setup, and a dozen other errands, Flash’s brevity might feel like a relief rather than a shortcoming.
Health advice
One service OpenAI highlighted from GPT-5 was health advice. I wouldn’t pick AI over my doctor in most cases, and, to be fair, OpenAI made it clear no one should, but if people are already going to ask ChatGPT for health advice, it makes sense to try and upgrade it. I asked about an imaginary, but very common health complaint, asking the two AIs about how: “I sometimes get mild headaches at night. What are common causes, and what lifestyle tweaks can help?”
GPT-5 handled this with measured care, explaining that it’s not uncommon, and laying out probable reasons such as dehydration, posture, screen time, irregular sleep, late-night caffeine, and so on. It connected each to headaches, then set out a list of specific, evidence-based adjustments I could make, explaining why each change might help, and noted when medical follow-up would be wise. It referenced reputable health organizations, which I did appreciate, as it made it seem more trustworthy.
Gemini Flash answered with a similar list, though more concisely stated, and emphasized hydration and a regular sleep schedule as particular focuses. It didn’t expand much on why these changes help, but did include some links as references, There was plenty there for someone looking for ideas, and honestly either would probably be acceptable to the average medical professional I suspect, though ChatGPT 5’s deeper explanations and tone might be more reassuring if the person was feeling worried and wanted to understand the underlying factors.
New myths
I next decided to compare both the ‘creativity’ of the two models and their image generation in one go, asking them to “Invent a completely original creation myth that hasn’t been told before, and then create a Renaissance-style painting to depict it.”
You can see ChatGPT’s painting on the left above and Gemini’s on the right. Both models went for images not too far off from what you might see in a church in Italy, with Gemini even suggesting a new Sistine Chapel ceiling.
According to ChatGPT, it painted “Aeothar, the First Sound, and Lysara, the Weaver of Night, whose union birthed the cosmos. Aeothar cradles the newborn Earth, his raised finger signaling the first vibration that would echo through creation. Beside him, Lysara holds a vast celestial sphere mapped with the Sun, planets, and constellations, as though she is stitching the pattern of the universe into being.”
Gemini envisioned a myth explaining that “the universe was born from the ‘Luminis Cordis,’ a pulsating heart of light. From it emerged two divine siblings: Aetheria, the goddess of light and order, and Umbror, the god of shadow and chaos. The universe we see is the result of their eternal cosmic dance, with Aetheria weaving the stars and galaxies and Umbror sculpting the voids and nebulae.”
Overpowered
GPT-5 undoubtedly brings enormous power and ability to ChatGPT when it comes to creating software, coding a website, or logically working out complex tasks and math problems. But, in day-to-day use, GPT-5 and Gemini 2.5 Flash are probably not very different. Both can plan a party, help you cook dinner, give health tips, and even invent a new mythology.
ChatGPT 5 may offer more detail at first, and may be more flexible in how it responds, but you can always ask Gemini follow-up questions. When it comes to the average AI chatbot user, the multiple steps, huge context window, and tone-perfect delivery are probably unnecessary.
GPT-5’s extra horsepower matters most when the challenge itself demands it. For everything else, you may as well pick whichever you feel more comfortable with. GPT-5 might immediately design and plan a whole wedding, including florists, while you might want to stick with just asking Gemini for a good florist to begin with. Most days, you don’t need the wedding planner, just help getting a nice bouquet.
