# GPT-4o

GPT-4o is an AI model released by OpenAI on May 13 2024. It has a 128k context window. At release it scored 12% on BullshitBench v2 and 49.9% on GPQA Diamond.

## Facts

| Field | Value |
| --- | --- |
| Model | GPT-4o |
| Developer | OpenAI |
| Release date | Monday, May 13 2024 |
| Licensing | Proprietary |
| Context window | 128k |

## API pricing

All rates in USD per 1,000,000 tokens, pay-as-you-go.

| Tier | Input | Cached input | Output |
| --- | --- | --- | --- |
| All documented contexts | $2.50 | $1.25 | $10.00 |

Verified August 18, 2026 against the first-party source: https://developers.openai.com/api/docs/models/gpt-4o

## Benchmark scores published at release

| Benchmark | Score | Source | What it measures |
| --- | --- | --- | --- |
| BullshitBench v2 | 12% | Lab | Given a confidently-worded but nonsensical prompt, does the AI spot that it makes no sense and push back — instead of playing along and inventing an answer? The score is how often it clearly called out the nonsense. Higher is better. |
| GPQA Diamond | 49.9% | Lab | Graduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. |

## About GPT-4o

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.

## Questions and answers

### When was GPT-4o released?

GPT-4o was released by OpenAI on Monday, May 13 2024.

### Who made GPT-4o?

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.


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Canonical page: https://aireleasetracker.com/model/openai/gpt-4o
Full dataset: https://aireleasetracker.com/llms-full.txt · JSON: https://aireleasetracker.com/models.json
Source: AI Release Tracker (https://aireleasetracker.com). Benchmark scores are the figures published by the releasing lab at launch.