Gemma 2 27B vs GPT-5.1-Codex
Gemma 2 27B costs 15.4x less per output token than GPT-5.1-Codex ($0.65 vs $10.00 per million). Updated October 21, 2026; no benchmark has tested both models yet.
- Coding
- No data
- Overall
- No data
- Output $/M
- $0.65
- Coding
- 15.3
- Overall
- No data
- Output $/M
- $10.00
Gemma 2 27B or GPT-5.1-Codex: which to pick
Only GPT-5.1-Codex has a coding score, 15.3 on the Vibe Coding Index; Gemma 2 27B has none, so the two cannot be ranked on coding.
Pick Gemma 2 27B for output tokens 15.4x cheaper ($0.65 vs $10.00 per million).
No benchmark has tested both yet. Gemma 2 27B has results on LMArena Text: coding, LMArena Text: software and IT and Epoch Capabilities Index; GPT-5.1-Codex on SWE-bench Verified, LMArena WebDev and LiveCodeBench (Vals AI). 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
Only GPT-5.1-Codex has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
No call
Only GPT-5.1-Codex has a AA Intelligence Index result, 23.7.
Directional only
Web design
Design Arena: websites
No call
Only GPT-5.1-Codex has a Design Arena: websites result, 1162.
Directional only
Long documents
Listed context window
GPT-5.1-Codex
GPT-5.1-Codex takes 400K tokens against 8K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Gemma 2 27B
Gemma 2 27B $0.0010, 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
- Gemma 2 27B not benchmarked, GPT-5.1-Codex 15.3 from 2 benchmarks.
- 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
- Gemma 2 27B $0.65 against GPT-5.1-Codex $10.00 per million output tokens, 15.4x apart.
- Context window
- Gemma 2 27B takes 8K tokens, GPT-5.1-Codex 400K.
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.
CodingDirectional onlySix of these boards feed the Vibe Coding Index11 boards measured
| Benchmark | Gemma 2 27B | GPT-5.1-Codex | Leader |
|---|---|---|---|
| SWE-bench Verified | Not measured | 66.0% | Only GPT-5.1-Codex measured |
| LMArena WebDev | Not measured | 1337 | Only GPT-5.1-Codex measured |
| LiveCodeBench (Vals AI) | Not measured | 85.5% | Only GPT-5.1-Codex measured |
| Vibe Code Bench (Vals AI) | Not measured | 13.1% | Only GPT-5.1-Codex measured |
| LiveCodeBench (Artificial Analysis run) | Not measured | 84.9% | Only GPT-5.1-Codex 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 |
| ALE-Bench | Not measured | 1244.9 | Only GPT-5.1-Codex measured |
| LMArena Text: coding | 1211 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: software and IT | 1228 | Not measured | Only Gemma 2 27B measured |
| LMArena WebDev: HTML | Not measured | 1346 | Only GPT-5.1-Codex measured |
| Neither model has a result on the other 28 boards here | |||
IntelligenceDirectional onlyPublic boards, shown as published, kept out of the index2 boards measured
| Benchmark | Gemma 2 27B | GPT-5.1-Codex | Leader |
|---|---|---|---|
| AA Intelligence Index | Not measured | 23.7 | Only GPT-5.1-Codex measured |
| Epoch Capabilities Index | 122.1 | Not measured | Only Gemma 2 27B measured |
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index4 boards measured
| Benchmark | Gemma 2 27B | 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 |
| τ²-Bench Telecom | Not measured | 83.0% | Only GPT-5.1-Codex measured |
| Neither model has a result on the other 37 boards here | |||
ReasoningDirectional onlyPublic boards, shown as published, kept out of the index6 boards measured
| Benchmark | Gemma 2 27B | GPT-5.1-Codex | Leader |
|---|---|---|---|
| GPQA Diamond (Artificial Analysis run) | Not measured | 86.0% | Only GPT-5.1-Codex measured |
| Humanity's Last Exam (Artificial Analysis run) | Not measured | 25.7% | Only GPT-5.1-Codex measured |
| GPQA Diamond (Epoch AI run) | 36.5% | Not measured | Only Gemma 2 27B measured |
| LMArena Text: hard prompts | 1198 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: expert | 1171 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: hard prompts in English | 1206 | Not measured | Only Gemma 2 27B measured |
| Neither model has a result on the other 16 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index6 boards measured
| Benchmark | Gemma 2 27B | 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 | 1.4% | Not measured | Only Gemma 2 27B measured |
| MATH level 5 | 27.9% | Not measured | Only Gemma 2 27B measured |
| LMArena Text: math | 1212 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: mathematical work | 1221 | Not measured | Only Gemma 2 27B measured |
| Neither model has a result on the other 7 boards here | |||
KnowledgeDirectional onlyPublic boards, shown as published, kept out of the index7 boards measured
| Benchmark | Gemma 2 27B | GPT-5.1-Codex | Leader |
|---|---|---|---|
| LegalBench (Vals AI) | 68.0% | Not measured | Only Gemma 2 27B measured |
| MMLU Pro (Artificial Analysis run) | Not measured | 86.0% | Only GPT-5.1-Codex measured |
| MMLU | 75.7% | Not measured | Only Gemma 2 27B measured |
| LMArena Text: science | 1228 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: medicine and healthcare | 1198 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: legal and government | 1241 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: business and finance | 1208 | Not measured | Only Gemma 2 27B measured |
| Neither model has a result on the other 11 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index5 boards measured
| Benchmark | Gemma 2 27B | GPT-5.1-Codex | Leader |
|---|---|---|---|
| Design Arena: websites | Not measured | 1162 | Only GPT-5.1-Codex measured |
| Design Arena: UI components | Not measured | 1237 | Only GPT-5.1-Codex measured |
| Design Arena: game dev | Not measured | 1138 | Only GPT-5.1-Codex measured |
| Design Arena: data viz | Not measured | 1213 | Only GPT-5.1-Codex measured |
| Design Arena: all code categories | Not measured | 1152 | Only GPT-5.1-Codex measured |
| Neither model has a result on the other 4 boards here | |||
GeneralDirectional onlyPublic boards, shown as published, kept out of the index21 boards measured
| Benchmark | Gemma 2 27B | GPT-5.1-Codex | Leader |
|---|---|---|---|
| IFBench | Not measured | 70.0% | Only GPT-5.1-Codex measured |
| Long context reasoning (AA-LCR) | Not measured | 69.3% | Only GPT-5.1-Codex measured |
| DTBench | 48.0% | Not measured | Only Gemma 2 27B measured |
| LMCA | 7.1% | Not measured | Only Gemma 2 27B measured |
| LMArena Text | 1231 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: instruction following | 1206 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: creative writing | 1240 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: English | 1242 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: non-English | 1217 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: Chinese | 1221 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: German | 1209 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: Japanese | 1175 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: Korean | 1174 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: French | 1248 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: Spanish | 1228 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: Russian | 1234 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: Polish | 1277 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: multi-turn | 1224 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: longer queries | 1230 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: writing and language | 1249 | Not measured | Only Gemma 2 27B measured |
| LMArena Text: entertainment and media | 1212 | Not measured | Only Gemma 2 27B measured |
| Neither model has a result on the other 25 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
Gemma 2 27B costs less
Repository review
50K input + 3K output tokens
Gemma 2 27B costs less
Agent loop
200K input + 10K output tokens
Gemma 2 27B 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 Gemma 2 27B | OpenAI GPT-5.1-Codex |
|---|---|---|
| Maker | OpenAI | |
| Weights | Open weights | No public weights listed |
| Released | July 13, 2024 | November 13, 2025 |
| Context window | 8K | 400K |
| Input $/Mtok | $0.65 | $1.25 |
| Output $/Mtok | $0.65 | $10.00 |
| Coding index | Not benchmarked | 15.3 |
| Independent measurements behind it | 0 | 2 |
| Cost per solved task | Not computable | $0.892 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Gemma 2 27B better than GPT-5.1-Codex for coding?
Only GPT-5.1-Codex has a coding score, 15.3 on the Vibe Coding Index; Gemma 2 27B has none, so the two cannot be ranked on coding. Pick Gemma 2 27B for output tokens 15.4x cheaper ($0.65 vs $10.00 per million).
Which is cheaper, Gemma 2 27B or GPT-5.1-Codex?
Gemma 2 27B costs $0.65 per million input tokens and $0.65 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, Gemma 2 27B or GPT-5.1-Codex?
GPT-5.1-Codex, with 400K tokens against 8K.
Has any benchmark tested both Gemma 2 27B and GPT-5.1-Codex?
No benchmark has tested both yet. Gemma 2 27B has results on LMArena Text: coding, LMArena Text: software and IT and Epoch Capabilities Index; GPT-5.1-Codex on SWE-bench Verified, LMArena WebDev and LiveCodeBench (Vals AI). Compare them on price and context instead. Data as of October 21, 2026.