Next → Jin’s Daily AI Trivia: Which OpenAI Model Is This?Today, OpenAI unveiled another “O-series” model—right on the heels of yesterday’s announcement of base model GPT‑4.1 (4.1, 4.1‑mini, and 4.1‑nano). The new lineup now includes:o3o3‑pro (coming soon)o4‑mini‑higho4‑miniConfused by all these names? Let me break down the evolution of the GPT and O-series models for you:GPT‑2 (2019)OpenAI’s first public release (1.5 B parameters).GPT‑3 (2021)Sparked the AI hype.Davinci model: 175 B parameters.Underpins the original ChatGPT.GPT‑3.5 (2022)Introduced the turbo variant and basic browsing.Marked the start of OpenAI’s subscription model.GPT‑4 (2023)Estimated at 1.76 T parameters.First multimodal model (text + image inputs).Free ChatGPT users access GPT‑4‑turbo (text-only).GPT‑4o (2024)“O” stands for “omni.”Real-time text, image, and audio input/output.Free users on image/audio get GPT‑4o‑mini; Plus users use GPT‑4o‑mini as their base.GPT‑4o Imagen (March 2025)Native image generation—an alternative to DALL·E 3.Powers the new “Ghibli-style” image output.GPT‑4.5 (2025)OpenAI’s largest, most expensive model yet.Available only to Plus and Pro subscribers.GPT‑4.1 (2025)A leaner, more cost-effective spin‑down of GPT‑4.5.Replaces GPT‑4o in the lineup.OpenAI‑o1 (2024)First “thinking” model with the “O” prefix.o1‑pro is the priciest, at $150/600 USD per million tokens.OpenAI‑o3 (2025)More efficient successor to o1.o3‑mini launched in January 2025 for Plus users.“o2” was skipped due to trademark issues.Full o3‑pro model to follow later this year.OpenAI‑o4 (2025)Released alongside o3 today.Currently available only as o4‑mini and o4‑mini‑high.Includes basic image-transform tools (crop/rotate) for better analysis.OpenAI rushed to launch o4 to compete with Gemini 2.5 Pro and Qwen. (Not even have a full o4 model)Initial Benchmarking:o4‑mini-high trails Gemini 2.5 Pro by a slim margin—but it’s significantly cheaper, especially for large-token contexts. If you need robust multimodal performance on a budget, o4‑mini is your go‑to.