Question 1

What does this Gemma 4 31B IT vs GPT-5.1 Codex mini comparison cover?

Accepted Answer

It brings together documented inputs and outputs, token limits, deployment terms and available pricing. When both models have source-linked, verified results on a shared benchmark, those results are shown with their individual sources. The comparison is a starting point for evaluating your own workload.

Question 2

Which is cheaper: Gemma 4 31B IT or GPT-5.1 Codex mini?

Accepted Answer

Gemma 4 31B IT lists $0.10 input and $0.34 output per 1M tokens. GPT-5.1 Codex mini lists $0.25 input and $2.00 output. The cheaper workload depends on the mix of input and output. Long-context tiers, caching, batch processing and retries can change the bill.

Question 3

Which has the larger context window: Gemma 4 31B IT or GPT-5.1 Codex mini?

Accepted Answer

Gemma 4 31B IT lists 262.14K tokens and GPT-5.1 Codex mini lists 400K. GPT-5.1 Codex mini therefore has the larger recorded context window, but capacity alone is not a quality score.

Question 4

Which is faster: Gemma 4 31B IT or GPT-5.1 Codex mini?

Accepted Answer

There is no matched speed measurement for both models with the same source, host, region and date. Test the same prompts at your expected concurrency and measure time to the first useful response as well as complete task time.

Question 5

What input and output types do Gemma 4 31B IT and GPT-5.1 Codex mini support?

Accepted Answer

Gemma 4 31B IT records text, image input and text output. GPT-5.1 Codex mini records text, image input and text output. “Not documented” means the current source record is incomplete; it does not prove that a modality is unsupported.

Question 6

Should I choose Gemma 4 31B IT or GPT-5.1 Codex mini?

Accepted Answer

Consider Gemma 4 31B IT if you need a lower listed input rate or a lower listed output rate. Consider GPT-5.1 Codex mini if you need larger context or larger maximum output. Gemma 4 31B IT offers downloadable weights; GPT-5.1 Codex mini is listed as a proprietary model. Compare licence terms and operating costs before choosing a deployment. Test both on the same representative examples and judge the output against your acceptance criteria. Include tool failures, retries and the time to a completed task.

Specification	Gemma 4 31B IT	GPT-5.1 Codex mini
Provider	Google	OpenAI
Listed pricing route	Google	OpenAI
Model family	gemma	gpt-codex
Accepted inputs	text, image	text, image
Produced outputs	text	text
Context window	262.14K	400KHigher
Max output	32.77K	128KHigher
Input price / 1M	$0.10Lower	$0.25
Output price / 1M	$0.34Lower	$2.00
Reasoning mode	Documented	Documented
Tool calling	Documented	Documented
Image input	Documented	Documented
Audio input	Not documented	Not documented
Structured output	Documented	Documented
License	Open weights	Proprietary

Gemma 4 31B IT vs GPT-5.1 Codex mini

Gemma 4 31B IT

GPT-5.1 Codex mini

Key differences

Pricing, limits and capabilities

Which model should you choose?

Documentation and model profiles

Questions people ask

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