Gemini 3.1 Pro Preview Custom Tools vs GPT-5.2 Chat

Gemini 3.1 Pro Preview Custom Tools and GPT-5.2 Chat cost about the same per output token ($12.00 vs $14.00 per million). Updated October 21, 2026; no benchmark has tested both models yet.

Replace Gemini 3.1 Pro Preview Custom Tools Replace GPT-5.2 Chat

Gemini 3.1 Pro Preview Custom ToolsGoogle

Coding: No data
Overall: No data
Output $/M: $12.00

GPT-5.2 ChatOpenAI

Coding: No data
Overall: No data
Output $/M: $14.00

vs $12.00 vs $14.00 per 1M output tokens. Gemini 3.1 Pro Preview Custom Tools is 1.2x cheaper.

Gemini 3.1 Pro Preview Custom Tools or GPT-5.2 Chat: which to pick

Neither model has a coding score yet, so the two cannot be ranked on coding.

Pick Gemini 3.1 Pro Preview Custom Tools for output tokens 1.2x cheaper ($12.00 vs $14.00 per million) and a larger context window (1.05M against 128K tokens).

Model AGemini 3.1 Pro Preview Custom ToolsGoogleNot benchmarkedNo coding benchmarkNo cost per solved task Model BGPT-5.2 ChatOpenAINot benchmarkedNo coding benchmarkNo cost per solved task

No benchmark has tested both yet. Gemini 3.1 Pro Preview Custom Tools has results on Vending-Bench 2; GPT-5.2 Chat has none yet. Compare them on price and context instead.

Which one for your work

Each card is decided by one number both models carry. Where only one has it, the card says so and makes no call.

Coding
Vibe Coding Index, six public coding benchmarks
No call
Neither has a coding score yet.
One side not measured
Long documents
Listed context window
Gemini 3.1 Pro Preview Custom Tools
Gemini 3.1 Pro Preview Custom Tools takes 1.05M tokens against 128K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Gemini 3.1 Pro Preview Custom Tools
Gemini 3.1 Pro Preview Custom Tools $0.0080, GPT-5.2 Chat $0.0088 per turn.
List prices

At a glance

Coding index: Gemini 3.1 Pro Preview Custom Tools not benchmarked, GPT-5.2 Chat not benchmarked.
Widest category: None yet: no category has been tested on both models.
Widest single gap: None yet: no benchmark has tested both models.
Output price: Gemini 3.1 Pro Preview Custom Tools $12.00 against GPT-5.2 Chat $14.00 per million output tokens, 1.2x apart.
Context window: Gemini 3.1 Pro Preview Custom Tools takes 1.05M tokens, GPT-5.2 Chat 128K.

Benchmark by benchmark

Every board either model has a result on, a category to a fold; bars are each result on a 0 to 100 scale. Only one model is measured on each, so no row names a leader.

Agentic workDirectional onlyPublic boards, shown as published, kept out of the index1 board measured

Agentic work benchmarks for Gemini 3.1 Pro Preview Custom Tools and GPT-5.2 Chat
Benchmark	Gemini 3.1 Pro Preview Custom Tools	GPT-5.2 Chat	Leader
Vending-Bench 2	$3,774	Not measured	Only Gemini 3.1 Pro Preview Custom Tools measured
Neither model has a result on the other 40 boards here

What each workload costs

Three fixed token mixes at each model's listed price, so per-token rates become a bill.

Chat turn

1K input + 500 output tokens

Gemini 3.1 Pro Preview Custom Tools$0.0080Fits in one request

GPT-5.2 Chat$0.0088Fits in one request

Gemini 3.1 Pro Preview Custom Tools costs less

Repository review

50K input + 3K output tokens

Gemini 3.1 Pro Preview Custom Tools$0.136Fits in one request

GPT-5.2 Chat$0.130Fits in one request

GPT-5.2 Chat costs less

Agent loop

200K input + 10K output tokens

Gemini 3.1 Pro Preview Custom Tools$0.520Fits in one request

GPT-5.2 Chat$0.490Exceeds the context window

GPT-5.2 Chat costs less

Listed OpenRouter rates, without cache or batch discounts. A workload that does not fit a model's context window would need splitting.

Specification differences

The leading value in a row is marked; a row with a missing value names no leader. Our two rows are marked in red.

Specifications of Gemini 3.1 Pro Preview Custom Tools and GPT-5.2 Chat
Specification	Google Gemini 3.1 Pro Preview Custom Tools	OpenAI GPT-5.2 Chat
Maker	Google	OpenAI
Weights	No public weights listed	No public weights listed
Released	February 25, 2026	December 10, 2025
Context window	1.05M	128K
Input $/Mtok	$2.00	$1.75
Output $/Mtok	$12.00	$14.00
Coding index	Not benchmarked	Not benchmarked
Independent measurements behind it	0	0
Cost per solved task	Not computable	Not computable
Source	OpenRouter listing	OpenRouter listing

Questions

Is Gemini 3.1 Pro Preview Custom Tools better than GPT-5.2 Chat for coding?

Neither model has a coding score yet, so the two cannot be ranked on coding. Pick Gemini 3.1 Pro Preview Custom Tools for output tokens 1.2x cheaper ($12.00 vs $14.00 per million) and a larger context window (1.05M against 128K tokens).

Which is cheaper, Gemini 3.1 Pro Preview Custom Tools or GPT-5.2 Chat?

Gemini 3.1 Pro Preview Custom Tools costs $2.00 per million input tokens and $12.00 per million output tokens; GPT-5.2 Chat costs $1.75 and $14.00. Cost per solved task is known for neither of them.

Which has the bigger context window, Gemini 3.1 Pro Preview Custom Tools or GPT-5.2 Chat?

Gemini 3.1 Pro Preview Custom Tools, with 1.05M tokens against 128K.

Has any benchmark tested both Gemini 3.1 Pro Preview Custom Tools and GPT-5.2 Chat?

No benchmark has tested both yet. Gemini 3.1 Pro Preview Custom Tools has results on Vending-Bench 2; GPT-5.2 Chat has none yet. Compare them on price and context instead. Data as of October 21, 2026.