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OpenAI

GPT-4o (Mar 2025)

Release page →

OpenAI

GPT-4.1 nano

Release page →

The basics

Released

Mar 27, 2025

Apr 14, 2025

What it does

Knowledge cutoff

The latest events it learned about

September 2023

April 2024More recent

Download

No: it runs on the maker's servers

Where to use it

OpenAI's app: ChatGPT ↗Also for developers, through an API

Price and limits, for developers

Input

Per million tokens

$2.50

$0.10Cheaper

Output

Per million tokens

$10.00

$0.40Cheaper

Cached input

Per million tokens

$1.25

$0.025Cheaper

Context window

How much it takes in at once

128K tokens about 96,000 words

1.05M tokens about 790,000 wordsBigger

Longest answer

16K tokens about 12,000 words

33K tokens about 25,000 wordsLonger

How they score

Combined test score

Epoch Capabilities Index · Epoch AI

129#150 of 237

127#156 of 237

Too close to call: GPT-4o (Mar 2025) and GPT-4.1 nano are within the margin of error.

Green marks the better of the two on each row, red the other. Rows where one side isn't listed, or where the gap is too close to call, stay plain.

Popular comparisons

Not sure where to start? Which AI should I use? gives a pick for what you want to do. How to read AI rankings explains the numbers.

Rankings from LMArena and Epoch AI, both CC BY 4.0, updated 2h ago. Developer prices, context windows and knowledge cutoffs from the labs' own listings on models.dev and from OpenRouter. The app links go to each maker's own app when no source says exactly where the model is available.