Question 1

What is GPT-4o?

Accepted Answer

GPT-4o is a large language model from OpenAI, released on 13 May 2024. OpenAI’s vision-and-voice flagship from 2024 — still a great default.

Question 2

When was GPT-4o released?

Accepted Answer

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

Question 3

How much does GPT-4o cost?

Accepted Answer

GPT-4o costs $2.50 per 1 million input tokens and $10.00 per 1 million output tokens via OpenAI’s API. At a typical 3:1 input/output ratio the blended cost works out to about $4.38 per 1M tokens.

Question 4

How smart is GPT-4o?

Accepted Answer

GPT-4o scores 72 out of 100 on our intelligence index — a strong production-tier composite of MMLU, MMLU Pro, GPQA, MATH and HumanEval benchmark scores. That places it #8 of 22 language models we track.

Question 5

What is the context window of GPT-4o?

Accepted Answer

GPT-4o has a 128k-token context window — roughly 96,000 words of text. That’s what you can fit into a single request (your prompt plus all uploaded documents and the model’s response combined).

Question 6

What is GPT-4o best for?

Accepted Answer

GPT-4o is most useful for general-purpose chat, voice apps and vision tasks. Its key strengths are strong multimodal, voice-native and mature ecosystem.

Question 7

How fast is GPT-4o?

Accepted Answer

GPT-4o generates around 110 output tokens per second with a typical time-to-first-token of 400 ms on the major API providers. Reasoning models that "think" before answering will appear slower on tokens-per-second since they spend time on internal chain-of-thought.

Question 8

Is GPT-4o better than GPT-5.5?

Accepted Answer

GPT-5.5 scores higher on our intelligence index (82 vs 72), so on the hardest tasks GPT-5.5 typically wins. GPT-4o can still be the better pick on price, latency or specific capabilities. See our full GPT-4o vs GPT-5.5 comparison at /ai-models/compare/gpt-5-5-vs-gpt-4o/.

Question 9

What is the best alternative to GPT-4o?

Accepted Answer

The closest alternatives to GPT-4o are GPT-5.5, GPT-5.5 mini and GPT-4o mini. Each shares most of GPT-4o’s use-cases — pick by price, context window or specific capability rather than headline intelligence.

Question 10

Is GPT-4o open source?

Accepted Answer

No. GPT-4o is proprietary — the weights are not released. Access is via OpenAI’s own API and partner platforms. For open-weights alternatives in the same tier, see our open-source AI models page.

Question 11

Can I use GPT-4o for free?

Accepted Answer

The consumer ChatGPT product offers free, rate-limited access to a version of GPT-4o and DALL·E 3. The OpenAI API itself is paid — though new accounts get a small starting credit. Microsoft Copilot also bundles GPT access at no extra cost on some tiers.

GPT-4o

At a glance

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