Gemini 4 Argon vs GPT-5.1-Codex
Updated October 21, 2026. 12 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
vs boards won of 12 shared
Decision reading
Pick Gemini 4 Argon for coding: it scores 80.5 on the Vibe Coding Index against 50.5 for GPT-5.1-Codex.
GPT-5.1-Codex is neither cheaper nor larger in context, and leads no benchmark both models were measured on.
Model AGemini 4 ArgonGoogle80.5/1002 independent benchmarksNo cost per solved taskModel BGPT-5.1-CodexOpenAI50.5/1002 independent benchmarks$0.892 per solved task
- Shared results
- 12
- Gemini 4 Argon only
- 80
- GPT-5.1-Codex only
- 14
- Like-for-like categories
- 5 of 9
Shared results can support a head-to-head reading. Results only one model has describe coverage, not superiority.
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, four public coding benchmarks
Gemini 4 Argon
Gemini 4 Argon scores 80.5 against 50.5.
2 benchmarks behind each score
Intelligence
AA Intelligence Index
Gemini 4 Argon
Gemini 4 Argon leads, 52.6 against 23.7.
Same board, both measured
Web design
Design Arena: websites
Gemini 4 Argon
Gemini 4 Argon leads, 1315 against 1162.
Same board, both measured
General
Vals Index
No call
Only Gemini 4 Argon has a Vals Index result, 69.2%.
Directional only
Long documents
Listed context window
Gemini 4 Argon
Gemini 4 Argon takes 1.05M tokens against 400K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
GPT-5.1-Codex
Gemini 4 Argon $0.0070, GPT-5.1-Codex $0.0063 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only GPT-5.1-Codex has the number, $0.892.
Directional only
At a glance
- Coding index
- Gemini 4 Argon 80.5 from 2 benchmarks, GPT-5.1-Codex 50.5 from 2 benchmarks.
- Widest category
- Coding, 49.6 points apart on average over 4 shared benchmarks.
- Widest single gap
- Vibe Code Bench (Vals AI): Gemini 4 Argon 91.9% against GPT-5.1-Codex 13.1%, 78.8 points apart on a 0 to 100 scale.
- Output price
- Both cost $10.00 per million output tokens.
- Context window
- Gemini 4 Argon takes 1.05M tokens, GPT-5.1-Codex 400K.
Benchmark by benchmark
First the score: boards each model leads, per category, where both have a result. Then every board, a category to a fold; bars are each result on a 0 to 100 scale, so compare the two in a row, not one row with another.
| Category | Gemini 4 Argon | Bars | GPT-5.1-Codex | Ties |
|---|---|---|---|---|
| Coding | 4 | 0 | ||
| Intelligence | 1 | 0 | ||
| Reasoning | 1 | 0 | ||
| Web design | 5 | 0 | ||
| General | 1 | 0 | ||
| All shared boards | 12 | 0 |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index40
| Benchmark | Gemini 4 Argon | GPT-5.1-Codex | Leader |
|---|---|---|---|
| SWE-bench Verified | Not measured | 66.0% | Only GPT-5.1-Codex measured |
| LiveBench coding | 89.7% | Not measured | Only Gemini 4 Argon measured |
| LMArena WebDev | 1678 | 1337 | Gemini 4 Argon |
| LiveCodeBench (Vals AI) | Not measured | 85.5% | Only GPT-5.1-Codex measured |
| Terminal-Bench 4 (Vals AI) | 57.6% | Not measured | Only Gemini 4 Argon measured |
| Vibe Code Bench (Vals AI) | 91.9% | 13.1% | Gemini 4 Argon |
| Code migration (Vals AI) | 68.2% | Not measured | Only Gemini 4 Argon measured |
| ProgramBench (Vals AI) | 2.5% | Not measured | Only Gemini 4 Argon measured |
| IOI (Vals AI) | 100.0% | Not measured | Only Gemini 4 Argon measured |
| Terminal-Bench 2.1 (Vals AI) | 57.7% | Not measured | Only Gemini 4 Argon measured |
| SWE-bench Multimodal (Vals AI) | 56.0% | Not measured | Only Gemini 4 Argon measured |
| Vibe Code Bench 1-100 (Vals AI) | 21.2% | Not measured | Only Gemini 4 Argon measured |
| CyberBench (Vals AI) | 77.9% | Not measured | Only Gemini 4 Argon measured |
| LiveCodeBench (Artificial Analysis run) | Not measured | 84.9% | Only GPT-5.1-Codex measured |
| SciCode | 61.8% | Not measured | Only Gemini 4 Argon measured |
| Terminal-Bench Hard (Artificial Analysis run) | Not measured | 34.8% | Only GPT-5.1-Codex measured |
| Terminal-Bench | Not measured | 57.8% | Only GPT-5.1-Codex measured |
| FrontierCode | 47.5% | Not measured | Only Gemini 4 Argon measured |
| FrontierSWE | 55.0% | Not measured | Only Gemini 4 Argon measured |
| ALE-Bench | 2100.1 | 1244.9 | Gemini 4 Argon |
| LMArena Text: coding | 1546 | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: software and IT | 1556 | Not measured | Only Gemini 4 Argon measured |
| LMArena WebDev: React | 1692 | Not measured | Only Gemini 4 Argon measured |
| LMArena WebDev: HTML | 1643 | 1346 | Gemini 4 Argon |
| Neither model has a result on the other 14 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Gemini 4 Argon | GPT-5.1-Codex | Leader |
|---|---|---|---|
| AA Intelligence Index | 52.6 | 23.7 | Gemini 4 Argon |
| Epoch Capabilities Index | 166.4 | Not measured | Only Gemini 4 Argon measured |
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index22 boards, none shared
| Benchmark | Gemini 4 Argon | GPT-5.1-Codex | Leader |
|---|---|---|---|
| Design Arena: agents building web apps | Not measured | 1018 | Only GPT-5.1-Codex measured |
| Design Arena: agents building full-stack apps | Not measured | 1086 | Only GPT-5.1-Codex measured |
| Design Arena: agents building mobile apps | Not measured | 1191 | Only GPT-5.1-Codex measured |
| Design Arena: spreadsheets | 1151 | Not measured | Only Gemini 4 Argon measured |
| LiveBench research | 83.1% | Not measured | Only Gemini 4 Argon measured |
| LiveBench browser | 92.0% | Not measured | Only Gemini 4 Argon measured |
| LiveBench long agentic | 69.9% | Not measured | Only Gemini 4 Argon measured |
| SREBench (Vals AI) | 44.3% | Not measured | Only Gemini 4 Argon measured |
| Finance Agent (Vals AI) | 65.4% | Not measured | Only Gemini 4 Argon measured |
| Tax Agent Bench (Vals AI) | 44.6% | Not measured | Only Gemini 4 Argon measured |
| Legal Research Bench (Vals AI) | 54.8% | Not measured | Only Gemini 4 Argon measured |
| Harvey's Legal Agent Benchmark (Vals AI) | 27.1% | Not measured | Only Gemini 4 Argon measured |
| Excel Modeling Benchmark (Vals AI) | 75.2% | Not measured | Only Gemini 4 Argon measured |
| BioMysteryBench (Vals AI) | 76.3% | Not measured | Only Gemini 4 Argon measured |
| Terminal-Bench-Science (Vals AI) | 44.3% | Not measured | Only Gemini 4 Argon measured |
| Vals Science Index | 55.4% | Not measured | Only Gemini 4 Argon measured |
| Time Horizon Index (Vals AI) | 52.5% | Not measured | Only Gemini 4 Argon measured |
| CUA-bench (Vals AI) | 4.8% | Not measured | Only Gemini 4 Argon measured |
| Robo-bench (Vals AI) | 0.8% | Not measured | Only Gemini 4 Argon measured |
| τ²-Bench Telecom | Not measured | 83.0% | Only GPT-5.1-Codex measured |
| APEX-Agents | 82.4% | Not measured | Only Gemini 4 Argon measured |
| Vending-Bench 2 | $13,718 | Not measured | Only Gemini 4 Argon measured |
| Neither model has a result on the other 17 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Gemini 4 Argon | GPT-5.1-Codex | Leader |
|---|---|---|---|
| LiveBench reasoning | 95.1% | Not measured | Only Gemini 4 Argon measured |
| MysteryMechanism (Vals AI) | 45.5% | Not measured | Only Gemini 4 Argon measured |
| GPQA Diamond (Artificial Analysis run) | Not measured | 86.0% | Only GPT-5.1-Codex measured |
| Humanity's Last Exam (Artificial Analysis run) | 57.1% | 25.7% | Gemini 4 Argon |
| GPQA Diamond (Epoch AI run) | 96.4% | Not measured | Only Gemini 4 Argon measured |
| ARC-AGI | 98.5% | Not measured | Only Gemini 4 Argon measured |
| ARC-AGI-2 | 91.3% | Not measured | Only Gemini 4 Argon measured |
| Chess puzzles | 59.0% | Not measured | Only Gemini 4 Argon measured |
| Mystery game puzzles | 64.0% | Not measured | Only Gemini 4 Argon measured |
| EBR-bench | 64.8% | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: hard prompts | 1546 | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: expert | 1550 | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: hard prompts in English | 1548 | Not measured | Only Gemini 4 Argon measured |
| Neither model has a result on the other 8 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index8 boards, none shared
| Benchmark | Gemini 4 Argon | GPT-5.1-Codex | Leader |
|---|---|---|---|
| AA Math Index | Not measured | 95.7 | Only GPT-5.1-Codex measured |
| AIME 2025 (Artificial Analysis run) | Not measured | 95.7% | Only GPT-5.1-Codex measured |
| OTIS Mock AIME | 100.0% | Not measured | Only Gemini 4 Argon measured |
| FrontierMath, tiers 1 to 3 | 86.0% | Not measured | Only Gemini 4 Argon measured |
| FrontierMath, tier 4 | 78.0% | Not measured | Only Gemini 4 Argon measured |
| ProofBench | 99.0% | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: math | 1536 | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: mathematical work | 1557 | Not measured | Only Gemini 4 Argon measured |
| Neither model has a result on the other 5 boards here | |||
KnowledgeDirectional onlyPublic boards, shown as published, kept out of the index8 boards, none shared
| Benchmark | Gemini 4 Argon | GPT-5.1-Codex | Leader |
|---|---|---|---|
| LegalBench (Vals AI) | 88.3% | Not measured | Only Gemini 4 Argon measured |
| MedCode (Vals AI) | 58.8% | Not measured | Only Gemini 4 Argon measured |
| MMLU Pro (Artificial Analysis run) | Not measured | 86.0% | Only GPT-5.1-Codex measured |
| SimpleQA Verified | 76.0% | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: science | 1548 | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: medicine and healthcare | 1555 | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: legal and government | 1548 | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: business and finance | 1525 | Not measured | Only Gemini 4 Argon measured |
| Neither model has a result on the other 9 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index50
| Benchmark | Gemini 4 Argon | GPT-5.1-Codex | Leader |
|---|---|---|---|
| Design Arena: websites | 1315 | 1162 | Gemini 4 Argon |
| Design Arena: UI components | 1333 | 1237 | Gemini 4 Argon |
| Design Arena: game dev | 1377 | 1138 | Gemini 4 Argon |
| Design Arena: data viz | 1334 | 1213 | Gemini 4 Argon |
| Design Arena: 3D | 1389 | Not measured | Only Gemini 4 Argon measured |
| Design Arena: all code categories | 1328 | 1153 | Gemini 4 Argon |
| LiveBench design | 73.7% | Not measured | Only Gemini 4 Argon measured |
| Neither model has a result on the other 2 boards here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Gemini 4 Argon | GPT-5.1-Codex | Leader |
|---|---|---|---|
| Vals Index | 69.2% | Not measured | Only Gemini 4 Argon measured |
| LiveBench data analysis | 85.2% | Not measured | Only Gemini 4 Argon measured |
| Public Benefits Bench (Vals AI) | 69.8% | Not measured | Only Gemini 4 Argon measured |
| SAGE (Vals AI) | 53.6% | Not measured | Only Gemini 4 Argon measured |
| MedScribe (Vals AI) | 87.4% | Not measured | Only Gemini 4 Argon measured |
| IFBench | Not measured | 70.0% | Only GPT-5.1-Codex measured |
| Long context reasoning (AA-LCR) | 79.7% | 69.3% | Gemini 4 Argon |
| DTBench | 97.6% | Not measured | Only Gemini 4 Argon measured |
| LMCA | 63.7% | Not measured | Only Gemini 4 Argon measured |
| Furniture assembly | 72.5% | Not measured | Only Gemini 4 Argon measured |
| LMArena Text | 1532 | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: instruction following | 1534 | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: creative writing | 1527 | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: English | 1538 | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: non-English | 1522 | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: Chinese | 1611 | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: Spanish | 1503 | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: Russian | 1534 | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: multi-turn | 1556 | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: longer queries | 1547 | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: writing and language | 1529 | Not measured | Only Gemini 4 Argon measured |
| LMArena Text: entertainment and media | 1527 | Not measured | Only Gemini 4 Argon measured |
| Neither model has a result on the other 24 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Gemini 4 Argon | GPT-5.1-Codex | Leader |
|---|---|---|---|
| Neither model has a result on 5 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 4 Argon$0.0070Fits in one request
GPT-5.1-Codex$0.0063Fits in one request
GPT-5.1-Codex costs less
Repository review
50K input + 3K output tokens
Gemini 4 Argon$0.130Fits in one request
GPT-5.1-Codex$0.092Fits in one request
GPT-5.1-Codex costs less
Agent loop
200K input + 10K output tokens
Gemini 4 Argon$0.500Fits in one request
GPT-5.1-Codex$0.350Fits in one request
GPT-5.1-Codex 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.
| Specification | Google Gemini 4 Argon | OpenAI GPT-5.1-Codex |
|---|---|---|
| Maker | OpenAI | |
| Weights | No public weights listed | No public weights listed |
| Released | October 13, 2026 | November 13, 2025 |
| Context window | 1.05M | 400K |
| Input $/Mtok | $2.00 | $1.25 |
| Output $/Mtok | $10.00 | $10.00 |
| Coding index | 80.5 | 50.5 |
| Independent measurements behind it | 2 | 2 |
| Cost per solved task | Not computable | $0.892 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Gemini 4 Argon better than GPT-5.1-Codex for coding?
Pick Gemini 4 Argon for coding: it scores 80.5 on the Vibe Coding Index against 50.5 for GPT-5.1-Codex. GPT-5.1-Codex is neither cheaper nor larger in context, and leads no benchmark both models were measured on.
Which is cheaper, Gemini 4 Argon or GPT-5.1-Codex?
Gemini 4 Argon costs $2.00 per million input tokens and $10.00 per million output tokens; GPT-5.1-Codex costs $1.25 and $10.00. Cost per solved task is known for GPT-5.1-Codex only.
Which has the bigger context window, Gemini 4 Argon or GPT-5.1-Codex?
Gemini 4 Argon, with 1.05M tokens against 400K.
How many benchmarks is the Gemini 4 Argon vs GPT-5.1-Codex comparison based on?
12 benchmarks have a result for both models as of October 21, 2026. Gemini 4 Argon's coding index rests on 2 independent benchmarks and GPT-5.1-Codex's on 2. Where only one model has a result, the page says so instead of naming a winner.