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5th March 2026 - Link Blog

Introducing GPT‑5.4. Two new API models: gpt-5.4 and gpt-5.4-pro, also available in ChatGPT and Codex CLI. August 31st 2025 knowledge cutoff, 1 million token context window. Priced slightly higher than the GPT-5.2 family with a bump in price for both models if you go above 272,000 tokens.

5.4 beats coding specialist GPT-5.3-Codex on all of the relevant benchmarks. I wonder if we'll get a 5.4 Codex or if that model line has now been merged into main?

Given Claude's recent focus on business applications it's interesting to see OpenAI highlight this in their announcement of GPT-5.4:

We put a particular focus on improving GPT‑5.4’s ability to create and edit spreadsheets, presentations, and documents. On an internal benchmark of spreadsheet modeling tasks that a junior investment banking analyst might do, GPT‑5.4 achieves a mean score of 87.3%, compared to 68.4% for GPT‑5.2.

Here's a pelican on a bicycle drawn by GPT-5.4:

alt text by GPT-5.4: Illustration of a cartoon pelican riding a bicycle, with a light gray background, dark blue bike frame and wheels, orange beak and legs, and motion lines suggesting movement.

And here's one by GPT-5.4 Pro, which took 4m45s and cost me $1.55:

Described by GPT-5.4: Illustration of a cartoon pelican riding a blue bicycle on pale green grass against a light gray background, with a large orange beak, gray-and-white body, and orange legs posed on the pedals.

Posted 5th March 2026 at 11:56 pm

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This is a link post by Simon Willison, posted on 5th March 2026.

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