GPT-4o
Released
GPT-4o is an AI model released by OpenAI on Monday, May 13 2024, 189 days after GPT-4 Turbo. It has a 128k token context window. Benchmark results (shown below) cover BullshitBench v2, and GPQA Diamond.
API pricing
- InputWhat you pay for everything you send the model — your question, plus any documents or earlier conversation you include with it.
- $2.50
- Cached inputA reduced rate for text you send over and over. If every request starts with the same instructions or the same document, the provider keeps a copy ready and charges less to read it again.
- $1.25
- OutputWhat you pay for the text the model writes back. It is normally the dearer half: producing an answer costs more than reading one.
- $10.00
Available from
Benchmarks
Reasoning & science
Robustness
About
GPT-4o — the "o" stands for omni — launched May 13, 2024 as OpenAI's first natively multimodal model, trained end-to-end across text, vision, and audio rather than stitching separate models together. Its headline feature was real-time voice conversation with near-human response latency, demoed live the day before Google I/O.
GPT-4o also marked a strategic shift: it brought GPT-4-class intelligence to ChatGPT's free tier for the first time, at half the API price of GPT-4 Turbo. The smaller GPT-4o mini followed in July 2024 and displaced GPT-3.5 as the default cheap model. GPT-4o remained ChatGPT's workhorse until the GPT-5 launch in August 2025.
Compare GPT-4o with
Suggested comparisons
Frequently asked questions
GPT-4o was released by OpenAI on Monday, May 13 2024.
GPT-4o was built by OpenAI. Creators of ChatGPT and the GPT series of models. Pioneered large-scale language model research.
GPT-4o costs $2.50 per million input tokens and $10.00 per million output tokens through the OpenAI API. Cached input is $1.25 per million tokens. Rates are pay-as-you-go API prices verified against OpenAI's published pricing on August 18, 2026.
GPT-4o reports 2 tracked benchmark scores — BullshitBench v2: 12%; GPQA Diamond: 49.9%. Scores are the figures published at release by OpenAI.
GPT-4o has a context window of 128k. That is the maximum amount of input plus output the model can hold in a single request.
No. GPT-4o is a proprietary model. The weights are not published — it is available only through the provider's own API, apps, or partner platforms.
OpenAI's previous tracked release was GPT-4 Turbo on Nov 6 2023, 189 days earlier. It was followed by GPT-4o mini on Jul 18 2024.