Gemini 4 Argon or GPT-5.5 Pro: which to choose?

Side-by-side comparison

Criterion	Gemini 4 Argon	GPT-5.5 Pro
Developer	Google DeepMind	OpenAI
Released	October 13, 2026	April 23, 2026
Capability index	95.3 / 100	96.9 / 100
Input price	$2	$30
Output price	$10	$180
Cost of a typical task	$0.06	$0.96
Context window	1,048,576 tokens	1,050,000 tokens
Maximum output	32,768 tokens	100,000 tokens
Reasoning mode	Yes	Yes
Tool calling	Yes	Yes
Accepted inputs	text, image, video, audio, PDF	text, image, PDF
Open weights	No	No
Knowledge cutoff	March 2026	December 1, 2025

Two models head to head

This comparison pits two frontier models, the ones you pick when quality comes first against each other: Gemini 4 Argon and GPT-5.5 Pro, one from Google DeepMind, the other from OpenAI. The first dates from October 13, 2026, the second from April 23, 2026.

All figures below come from public sources checked on October 22, 2026: models.dev and OpenRouter for prices and capabilities, Epoch AI for scores.

Which one is more capable?

On our capability index, Gemini 4 Argon scores 95.3 out of 100 and GPT-5.5 Pro 96.9. GPT-5.5 Pro leads by 1.6 points.

On the 3 benchmarks reported for both, Gemini 4 Argon wins 1 time and GPT-5.5 Pro 1:

GPQA Diamond (PhD-level science questions): Gemini 4 Argon 96.4%, GPT-5.5 Pro 93.9%
OTIS Mock AIME (competition mathematics problems): Gemini 4 Argon 100%, GPT-5.5 Pro 100%
FrontierMath (very hard research-level mathematics): Gemini 4 Argon 86%, GPT-5.5 Pro 87.7%

Which one costs less?

Gemini 4 Argon costs $2 per million input tokens and $10 per million output tokens; GPT-5.5 Pro costs $30 and $180.

For a typical agent task (read 20,000 tokens, write 2,000), expect $0.06 with Gemini 4 Argon versus $0.96 with GPT-5.5 Pro. Gemini 4 Argon is 16 times cheaper, a gap that adds up quickly over 1,000 tasks: $900 difference.

Run the numbers with your own volumes in the agent cost calculator.

Context and capabilities

GPT-5.5 Pro reads more in one go: 1,050,000 tokens of context (roughly 1,575 pages), versus 1,048,576 for Gemini 4 Argon.

Reasoning mode: Gemini 4 Argon yes, GPT-5.5 Pro yes. Tool calling: Gemini 4 Argon yes, GPT-5.5 Pro yes. Image input: Gemini 4 Argon yes, GPT-5.5 Pro yes.

Neither publishes its weights: both are used through an API.

Knowledge cutoff: March 2026 for Gemini 4 Argon, December 1, 2025 for GPT-5.5 Pro.

In short

Our reading of the data:

Choose Gemini 4 Argon for a lower cost and a more recent release.
Choose GPT-5.5 Pro for a higher capability index.

This verdict relies on public figures; it does not replace a trial on your own tasks.

Frequently asked questions

Gemini 4 Argon or GPT-5.5 Pro: which is better?

On our index (Epoch AI data), Gemini 4 Argon scores 95.3 and GPT-5.5 Pro 96.9 out of 100. The best choice also depends on price and on your use case.

Which one is cheaper?

Gemini 4 Argon. To read 20,000 tokens and write 2,000, expect $0.06 with Gemini 4 Argon and $0.96 with GPT-5.5 Pro (prices as of October 22, 2026).

Which one has the larger context window?

GPT-5.5 Pro, with 1,050,000 tokens versus 1,048,576.

Can I run Gemini 4 Argon or GPT-5.5 Pro on my own servers?

No: both are closed models, available through an API.

Gemini 4 Argon vs GPT-5.5 Pro