When was GPT-4o released?

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.

How much does GPT-4o cost?

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.

What benchmark scores did GPT-4o get?

GPT-4o reports 2 tracked benchmark scores — BullshitBench v2: 12%; GPQA Diamond: 49.9%. Scores are the figures published at release by OpenAI.

What is the context window of GPT-4o?

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.

Is GPT-4o open source?

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.

What came before and after GPT-4o?

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.

GPT-4o

Released May 13 2024

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

Input: $2.50
Cached input: $1.25
Output: $10.00

USD per 1M tokens

Available from


Azure	$2.50	$10.00	128K

USD per 1M tokens

Benchmarks

Reasoning & science

GPQA Diamond

49.9%

#54 of 59

Robustness

BullshitBench v2

12%

#69 of 77

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

GPT-4o

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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.