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Data

Gemma 4 31B vs GPT-5.1-Codex

Updated November 13, 2026. Rank says GPT-5.1-Codex is ahead. Price, access, and your workload can each overturn that. Public scores include evidence status and uncertainty.

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Decision reading

GPT-5.1-Codex has the higher public point estimate, 50.88 versus 28.81. Their conditional score ranges overlap. These ranges do not establish rank confidence. 1 results are shared. Category rows resting on Estimated evidence or different benchmark sets are marked directional and do not name a winner.

Model A
Google logo

Google

28.81/100

Estimated · Public rank #175

Conditional range 19.1–38.5

Model B
OpenAI logo

OpenAI

50.88/100

Estimated · Public rank #99

Conditional range 36.5–65.2

API price per 1M tokens

Gemma 4 31B: No comparable API price

GPT-5.1-Codex: $1.25 input / $10 output

Context window

Gemma 4 31B: 256K

GPT-5.1-Codex: 400K

Released

Gemma 4 31B: April 2, 2026

GPT-5.1-Codex: November 13, 2025

Shared results
1
Gemma 4 31B only
12
GPT-5.1-Codex only
3
Like-for-like categories
0 / 8
Estimated: Gemma 4 31B and GPT-5.1-Codex. Conditional ranges do not establish rank confidence.How the comparison works

Which one for your work

Recommendations appear only when a shared evidence basis or an explicit operating constraint supports the call. Secondary and unsupported use cases stay disclosed below the initial list.

  • Long documents

    Prompts that approach the documented context limit

    GPT-5.1-Codex

    GPT-5.1-Codex has the larger documented context window.

    Confidence: documented
Show secondary and unsupported calls
  • Coding work

    Code generation, repair, and software-engineering tasks

    Not enough matched evidence

    GPT-5.1-Codex is scored on Estimated evidence for coding, so the reading is directional rather than like-for-like.

    Confidence: limited
  • Agentic work

    Tool use, computer use, and multi-step task completion

    Not enough matched evidence

    GPT-5.1-Codex is not ranked on the public lane for agentic, so no winner is named for agentic.

    Confidence: limited
  • Chat turn cost

    1K fresh input + 500 output tokens

    Not enough matched evidence

    A complete comparable API-rate estimate is not available for both models.

    Confidence: listed-rates
  • Cache-heavy agent loop cost

    200K cached + 20K fresh input + 10K output tokens

    Not enough matched evidence

    A complete comparable API-rate estimate is not available for both models.

    Confidence: listed-rates
  • Repository review cost

    50K fresh input + 3K output tokens

    Not enough matched evidence

    A complete comparable API-rate estimate is not available for both models.

    Confidence: listed-rates

Which one for a specific job

Choose a job from the LLM Selector's task catalog to see the category row it rests on, under the same basis rules as the table below. A directional row stays directional; choosing a job never creates a winner.

The same task catalog as the LLM Selector. Each job names the evidence surface it rests on; nothing here adds a new score.

28.8Gemma 4 31B36.3GPT-5.1-Codex

Directional only · BenchAlign v5.8

GPT-5.1-Codex has the higher coding point estimate. Conditional score ranges do not establish rank confidence.

Coding scores combine specific tasks and setups. Match the editor, harness, and effort to your workflow.

Same basis rules as the category table below

Or describe your own job

The LLM Selector reads what you need a model for and returns a shortlist, ranked in the same order the job pages publish.

Describe the task and constraints. This selector recommends models; it cannot carry out the task or access your files and accounts.

We keep what you type here, drafts included, for 180 days, and after that only the job and requirements read from it. Nothing is tied to your IP address or account. Leave out names and other personal details. Privacy

What is actually comparable

Shared results can support a head-to-head reading. Results present for only one model describe coverage, not superiority.

4 categories rest on Estimated evidence or different evidence sets. Those rows remain visible for coverage context but do not name a winner.

Shape of the matched evidence

Only shared public evidence is shown. Sparse evidence stays a ruled list rather than being closed into a radar shape.

A shared-evidence shape is not available.

BenchLM does not draw a radar or infer missing axes when the matched evidence is too sparse.

Category results, on a stated basis

Each row shows the public-lane category score for both models: the BenchAlign v5.8 lane for agentic, coding, reasoning, multimodal, and knowledge, and the weighted public rows elsewhere, with the same rank each model page reports. A row is like-for-like only when both scores rest on Supported evidence or the same weighted set. Directional and not-comparable rows remain visible, but they never receive a winner.

Coding

Directional only
Gemma 4 31B
28.8
Supported · #107/162
GPT-5.1-Codex
36.3
Estimated · #89/162
Basis
BenchAlign v5.8 lane · 3 vs 2 public rows
Reading
Directional only

Reasoning

Directional only
Gemma 4 31B
32.0
Supported · #109/160
GPT-5.1-Codex
45.2
Estimated · #70/160
Basis
BenchAlign v5.8 lane · 1 vs 0 public rows
Reading
Directional only

Knowledge

Directional only
Gemma 4 31B
36.7
Supported · #121/180
GPT-5.1-Codex
53.1
Estimated · #76/180
Basis
BenchAlign v5.8 lane · 4 vs 0 public rows
Reading
Directional only

Instruction following

Directional only
Gemma 4 31B
92.9
#16/157
GPT-5.1-Codex
85.6
#52/157
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Directional only

Agentic

Not comparable
Gemma 4 31B
12.5
Estimated · #133/135
GPT-5.1-Codex
Not ranked
Basis
BenchAlign v5.8 lane · 3 vs 2 public rows
Reading
Not comparable

Multimodal

Not comparable
Gemma 4 31B
47.3
Supported · #60/67
GPT-5.1-Codex
Not ranked
Basis
BenchAlign v5.8 lane · 2 vs 0 public rows
Reading
Not comparable

Multilingual

Not comparable
Gemma 4 31B
Not ranked
GPT-5.1-Codex
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Math

Not comparable
Gemma 4 31B
Not ranked
GPT-5.1-Codex
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Ranks count the models scored in each category’s lane, so the agentic, coding, reasoning, multimodal, and knowledge denominators (BenchAlign v5.8) differ from the provisional-lane categories. Unranked scores sit on the provisional lane’s scale but never name a winner. Like-for-like rows within 0.5 points read as a practical tie.

Supported evidence per lane · bars run 0–100Methodology

What each workload costs

Three fixed token mixes turn per-token rates into comparable decisions. Each scenario states context fit and whether cached input had to fall back to the published list-input rate.

Chat turn

1K fresh input + 500 output tokens

Gemma 4 31B
Self-hosted; infrastructure cost varies
Fits in one request
GPT-5.1-Codex
$0.00625
Fits in one request

Gemma 4 31B has no comparable published API token rate.

Repository review

50K fresh input + 3K output tokens

Gemma 4 31B
Self-hosted; infrastructure cost varies
Fits in one request
GPT-5.1-Codex
$0.0925
Fits in one request

Gemma 4 31B has no comparable published API token rate.

Cache-heavy agent loop

200K cached + 20K fresh input + 10K output tokens

Gemma 4 31B
Self-hosted; infrastructure cost varies
Fits in one request
Cached-input rate unavailable
GPT-5.1-Codex
$0.15
Fits in one request

Gemma 4 31B has no comparable published API token rate.

Cached input falls back to the list input rate only where a cached rate is unpublished

Price against score, among all priced models

Overall score against output price per 1M tokens, one model per family. Pricing as of November 12, 2026.

GPT-5.1-Codex

20406080100$0.10$0.50$1$5$10$50$100Output price, $ per 1M tokens (log)Overall score
  • Gemma 4 31B has no public API price, so it is not plotted.
  • 28 models score at least as high as GPT-5.1-Codex for the same price or less. The nearest is Gemini 4 Carbon (score 89.2, also $10.00 per 1M output tokens).

Gray dots are the other priced models. The dark step line is the efficiency frontier: for a model under it, another model costs no more and scores at least as high.

See GPT-5.1-Codex on the full price vs performance chart

Specification differences

Sourced differences are shown directly. Missing facts stay explicit instead of being inferred from a model name or family.

Cached-input rate

A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.

Gemma 4 31B

No comparable hosted API rate

GPT-5.1-Codex

$0.125 per 1M cached input tokens

OpenAI GPT-5.1-Codex model documentation

Provider availability

Gemma 4 31B

Generally Available · Gemini API, Google AI Studio, open weights

Google Gemma Gemini API guide

GPT-5.1-Codex

Not sourced

Reasoning profile

Gemma 4 31B

Reasoning

GPT-5.1-Codex

Reasoning

Weight access

Gemma 4 31B

Open Weight

GPT-5.1-Codex

Proprietary

License

Gemma 4 31B

Open Weight

GPT-5.1-Codex

Proprietary

Release date

Gemma 4 31B

2026-04-02

GPT-5.1-Codex

2025-11-13

If you already use one of these models

Deployment change
The models list different providers, so authentication, endpoint behavior, limits, and feature support may change.
Quality signal
GPT-5.1-Codex has the higher public point estimate, 50.88 versus 28.81. Their conditional score ranges overlap. These ranges do not establish rank confidence.
Workload cost
A complete comparable API-rate estimate is not available for both models.
Context tradeoff
GPT-5.1-Codex has the larger documented window (400K).
Run the same representative tasks against both endpoints before changing production traffic.

Questions

Which is better, Gemma 4 31B or GPT-5.1-Codex?

GPT-5.1-Codex has the higher public point estimate, 50.88 versus 28.81. Their conditional score ranges overlap. These ranges do not establish rank confidence. The page therefore keeps the decision tied to the specific documented workload.

Which is better for coding, Gemma 4 31B or GPT-5.1-Codex?

GPT-5.1-Codex scores higher for coding on the public lane, 36.3 to 28.8. GPT-5.1-Codex is scored on Estimated evidence for coding, so the reading is directional rather than like-for-like. BenchLM does not name a winner for coding from a directional reading; read the shared benchmark rows directly and test the models on the same task set.

Which is better for agentic tasks, Gemma 4 31B or GPT-5.1-Codex?

GPT-5.1-Codex is not ranked on the public lane for agentic tasks, so no winner is named for agentic tasks.

Which costs less, Gemma 4 31B or GPT-5.1-Codex?

Both models do not have comparable published API token rates, so this page does not name a universal price winner.

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

GPT-5.1-Codex has the larger documented context window: 400K, compared with 256K.

Self-host vs API cost

Estimates at 50,000 req/day · 1000 tokens/req average.

Gemma 4 31B
API / mo (Novita AI)$405
Self-host / mo$298
Break-even37M/day
GPT-5.1-Codex
API / mo$8,438
Self-host / moNot listed
Break-even—
Proprietary model — self-hosting not applicable.
Model the full break-even

Benchmark evidence

The full public result ledger is available for audit without forcing a wide desktop table onto a phone.

Browse raw public benchmark evidence16 rows

Agentic

  • b3 Agent Security

    Gemma 4 31B83.0%
    Source
    GPT-5.1-Codex—

    Not directly comparable

  • Cyber Misuse Refusal

    Gemma 4 31B84.0%
    Source
    GPT-5.1-Codex—

    Not directly comparable

  • Gemma 4 31B35.26%
    GPT-5.1-Codex49.68%

    GPT-5.1-Codex leads this result

  • JobBench

    Gemma 4 31B—
    GPT-5.1-Codex26.2%
    Source

    Not directly comparable

Coding

  • LiveCodeBench v6

    Gemma 4 31B80.0%
    Source
    GPT-5.1-Codex—

    Not directly comparable

  • SWE-Rebench

    Gemma 4 31B41.6%
    Source
    GPT-5.1-Codex—

    Not directly comparable

  • React Native Evals

    Gemma 4 31B75.2%
    Source
    GPT-5.1-Codex—

    Not directly comparable

  • Vibe Code Bench

    Gemma 4 31B—
    GPT-5.1-Codex13.12%
    Source

    Not directly comparable

  • LiveCodeBench (Vals)

    Gemma 4 31B—
    GPT-5.1-Codex85.6%
    Source

    Not directly comparable

Reasoning

  • MRCRv2

    Gemma 4 31B66.4%
    Source
    GPT-5.1-Codex—

    Not directly comparable

Multimodal

  • ParseBench-1

    Gemma 4 31B62.40%
    Source
    GPT-5.1-Codex—

    Not directly comparable

  • MMMU-Pro

    Gemma 4 31B76.9%
    Source
    GPT-5.1-Codex—

    Not directly comparable

Knowledge

  • GPQA

    Gemma 4 31B84.3%
    Source
    GPT-5.1-Codex—

    Not directly comparable

  • MMLU-Pro

    Gemma 4 31B85.2%
    Source
    GPT-5.1-Codex—

    Not directly comparable

  • HLE

    Gemma 4 31B26.5%
    Source
    GPT-5.1-Codex—

    Not directly comparable

  • HLE w/o tools

    Gemma 4 31B19.5%
    Source
    GPT-5.1-Codex—

    Not directly comparable

16 public results · 1 shared

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Last updated November 13, 2026