Gemini 3.8 Flash vs Gemma 4 31B
Gemini 3.8 Flash leads Gemma 4 31B on coding, 61.6 to 39.0 on the Vibe Coding Index, and Gemma 4 31B costs 9.4x less per output token ($0.40 vs $3.75 per million). Updated October 21, 2026; 63 benchmarks have a result for both.
Gemini 3.8 Flash or Gemma 4 31B: which to pick
Pick Gemini 3.8 Flash for coding: it scores 61.6 on the Vibe Coding Index against 39.0 for Gemma 4 31B.
Pick Gemma 4 31B for output tokens 9.4x cheaper ($0.40 vs $3.75 per million) and work measured by SAGE (Vals AI), where it leads.
- Shared results
- 63
- Gemini 3.8 Flash only
- 65
- Gemma 4 31B only
- 8
- Like-for-like categories
- 8 of 9
Only benchmarks that tested both models count toward a pick; a result only one model has is shown but not compared.
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
Gemini 3.8 Flash
Gemini 3.8 Flash scores 61.6 against 39.0.
6 and 2 benchmarks behind the scores
Intelligence
AA Intelligence Index
Gemini 3.8 Flash
Gemini 3.8 Flash leads, 40.9 against 14.7.
Same board, both measured
Agentic work
AA Agentic Index
Gemini 3.8 Flash
Gemini 3.8 Flash leads, 40.2 against 4.2.
Same board, both measured
Reasoning
GPQA Diamond
No call
Only Gemini 3.8 Flash has a GPQA Diamond result, 94.4%.
Directional only
Knowledge
MMLU Pro
No call
Only Gemini 3.8 Flash has a MMLU Pro result, 90.2%.
Directional only
Web design
Design Arena: websites
No call
Only Gemini 3.8 Flash has a Design Arena: websites result, 1300.
Directional only
General
Vals Index
No call
Only Gemini 3.8 Flash has a Vals Index result, 56.0%.
Directional only
Long documents
Listed context window
Gemini 3.8 Flash
Gemini 3.8 Flash takes 1.05M tokens against 262K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Gemma 4 31B
Gemini 3.8 Flash $0.0026, Gemma 4 31B $0.0003 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Gemini 3.8 Flash has the number, $2.74.
Directional only
At a glance
- Coding index
- Gemini 3.8 Flash 61.6 from 6 benchmarks, Gemma 4 31B 39.0 from 2 benchmarks.
- Widest category
- Agentic work, 36.9 points apart on average over 4 shared benchmarks.
- Widest single gap
- LiveBench browser: Gemini 3.8 Flash 64.0% against Gemma 4 31B 4.0%, 60.0 points apart on a 0 to 100 scale.
- Output price
- Gemini 3.8 Flash $3.75 against Gemma 4 31B $0.40 per million output tokens, 9.4x apart.
- Context window
- Gemini 3.8 Flash takes 1.05M tokens, Gemma 4 31B 262K.
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 3.8 Flash | Bars | Gemma 4 31B | Ties |
|---|---|---|---|---|
| Coding | 11 | 0 | ||
| Intelligence | 2 | 0 | ||
| Agentic work | 4 | 0 | ||
| Reasoning | 9 | 0 | ||
| Math | 3 | 0 | ||
| Knowledge | 7 | 0 | ||
| Web design | 1 | 0 | ||
| General | 25 | 1 | ||
| All shared boards | 62 | 1 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index110
| Benchmark | Gemini 3.8 Flash | Gemma 4 31B | Leader |
|---|---|---|---|
| LiveBench coding | 82.2% | 49.0% | Gemini 3.8 Flash |
| LMArena WebDev | 1585 | 1367 | Gemini 3.8 Flash |
| AA Coding Index | 76.3 | 43.4 | Gemini 3.8 Flash |
| LiveCodeBench (Vals AI) | 89.5% | Not measured | Only Gemini 3.8 Flash measured |
| SWE-bench Verified (Vals AI) | 80.0% | Not measured | Only Gemini 3.8 Flash measured |
| Terminal-Bench 4 (Vals AI) | 19.7% | Not measured | Only Gemini 3.8 Flash measured |
| Vibe Code Bench (Vals AI) | 78.7% | Not measured | Only Gemini 3.8 Flash measured |
| Code migration (Vals AI) | 36.5% | Not measured | Only Gemini 3.8 Flash measured |
| ProgramBench (Vals AI) | 1.0% | Not measured | Only Gemini 3.8 Flash measured |
| IOI (Vals AI) | 56.9% | Not measured | Only Gemini 3.8 Flash measured |
| Terminal-Bench 2.1 (Vals AI) | 81.3% | Not measured | Only Gemini 3.8 Flash measured |
| SWE-bench Multimodal (Vals AI) | 40.8% | Not measured | Only Gemini 3.8 Flash measured |
| Vibe Code Bench 1-100 (Vals AI) | 18.8% | Not measured | Only Gemini 3.8 Flash measured |
| SkillsBench (Vals AI) | 58.0% | Not measured | Only Gemini 3.8 Flash measured |
| CyberBench (Vals AI) | 43.8% | Not measured | Only Gemini 3.8 Flash measured |
| SciCode | 56.6% | 45.5% | Gemini 3.8 Flash |
| Terminal-Bench Hard (Artificial Analysis run) | Not measured | 36.4% | Only Gemma 4 31B measured |
| FrontierCode | 41.2% | Not measured | Only Gemini 3.8 Flash measured |
| FrontierSWE | 19.6% | Not measured | Only Gemini 3.8 Flash measured |
| WeirdML | 84.8% | 52.3% | Gemini 3.8 Flash |
| ALE-Bench | 1269.7 | 925.5 | Gemini 3.8 Flash |
| LMArena Text: coding | 1508 | 1459 | Gemini 3.8 Flash |
| LMArena Text: software and IT | 1507 | 1463 | Gemini 3.8 Flash |
| LMArena WebDev: React | 1577 | 1359 | Gemini 3.8 Flash |
| LMArena WebDev: HTML | 1616 | 1380 | Gemini 3.8 Flash |
| LMArena WebDev: from an image | 1593 | Not measured | Only Gemini 3.8 Flash measured |
| SciCode | 12.3% | 8.9% | Gemini 3.8 Flash |
| Neither model has a result on the other 12 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Gemini 3.8 Flash | Gemma 4 31B | Leader |
|---|---|---|---|
| AA Intelligence Index | 40.9 | 14.7 | Gemini 3.8 Flash |
| Epoch Capabilities Index | 157.4 | 143.0 | Gemini 3.8 Flash |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | Gemini 3.8 Flash | Gemma 4 31B | Leader |
|---|---|---|---|
| AA Agentic Index | 40.2 | 4.2 | Gemini 3.8 Flash |
| Design Arena: agents building web apps | 1238 | Not measured | Only Gemini 3.8 Flash measured |
| Design Arena: agents building full-stack apps | 1244 | Not measured | Only Gemini 3.8 Flash measured |
| Design Arena: agents building mobile apps | 1236 | Not measured | Only Gemini 3.8 Flash measured |
| Design Arena: agents building Android apps | 1074 | Not measured | Only Gemini 3.8 Flash measured |
| Design Arena: agents building Godot games | 1273 | Not measured | Only Gemini 3.8 Flash measured |
| Design Arena: PowerPoint slides | 1177 | Not measured | Only Gemini 3.8 Flash measured |
| Design Arena: spreadsheets | 1056 | Not measured | Only Gemini 3.8 Flash measured |
| LiveBench research | 79.1% | 44.4% | Gemini 3.8 Flash |
| LiveBench browser | 64.0% | 4.0% | Gemini 3.8 Flash |
| LiveBench long agentic | 30.1% | 13.3% | Gemini 3.8 Flash |
| SREBench (Vals AI) | 11.1% | Not measured | Only Gemini 3.8 Flash measured |
| Finance Agent (Vals AI) | 61.4% | Not measured | Only Gemini 3.8 Flash measured |
| Tax Agent Bench (Vals AI) | 32.1% | Not measured | Only Gemini 3.8 Flash measured |
| Legal Research Bench (Vals AI) | 38.9% | Not measured | Only Gemini 3.8 Flash measured |
| Harvey's Legal Agent Benchmark (Vals AI) | 12.1% | Not measured | Only Gemini 3.8 Flash measured |
| Excel Modeling Benchmark (Vals AI) | 72.2% | Not measured | Only Gemini 3.8 Flash measured |
| BioMysteryBench (Vals AI) | 62.2% | Not measured | Only Gemini 3.8 Flash measured |
| Terminal-Bench-Science (Vals AI) | 8.6% | Not measured | Only Gemini 3.8 Flash measured |
| Vals Science Index | 35.8% | Not measured | Only Gemini 3.8 Flash measured |
| Time Horizon Index (Vals AI) | 18.8% | Not measured | Only Gemini 3.8 Flash measured |
| CUA-bench (Vals AI) | 4.2% | Not measured | Only Gemini 3.8 Flash measured |
| τ²-Bench Telecom | Not measured | 65.5% | Only Gemma 4 31B measured |
| APEX-Agents | 64.3% | Not measured | Only Gemini 3.8 Flash measured |
| Remote Labor Index | 5.8% | Not measured | Only Gemini 3.8 Flash measured |
| Vending-Bench 2 | $5,094 | Not measured | Only Gemini 3.8 Flash measured |
| Neither model has a result on the other 15 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index90
| Benchmark | Gemini 3.8 Flash | Gemma 4 31B | Leader |
|---|---|---|---|
| GPQA Diamond | 94.4% | Not measured | Only Gemini 3.8 Flash measured |
| LiveBench reasoning | 89.3% | 68.3% | Gemini 3.8 Flash |
| MysteryMechanism (Vals AI) | 36.5% | Not measured | Only Gemini 3.8 Flash measured |
| MMMU Pro (Vals AI) | 89.1% | Not measured | Only Gemini 3.8 Flash measured |
| GPQA Diamond (Artificial Analysis run) | 95.3% | 85.7% | Gemini 3.8 Flash |
| Humanity's Last Exam (Artificial Analysis run) | 47.8% | 23.6% | Gemini 3.8 Flash |
| GPQA Diamond (Epoch AI run) | 95.4% | 75.8% | Gemini 3.8 Flash |
| ARC-AGI | 98.5% | Not measured | Only Gemini 3.8 Flash measured |
| ARC-AGI-2 | 89.2% | Not measured | Only Gemini 3.8 Flash measured |
| Chess puzzles | 58.0% | Not measured | Only Gemini 3.8 Flash measured |
| Mystery game puzzles | 47.0% | Not measured | Only Gemini 3.8 Flash measured |
| LMArena Text: hard prompts | 1509 | 1448 | Gemini 3.8 Flash |
| LMArena Text: expert | 1526 | 1464 | Gemini 3.8 Flash |
| LMArena Text: hard prompts in English | 1504 | 1456 | Gemini 3.8 Flash |
| LMArena Vision: diagrams | 1345 | 1283 | Gemini 3.8 Flash |
| LMArena Vision: homework | 1351 | 1310 | Gemini 3.8 Flash |
| Kagi LLM Benchmark | Not measured | 63.5% | Only Gemma 4 31B measured |
| Neither model has a result on the other 5 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index30
| Benchmark | Gemini 3.8 Flash | Gemma 4 31B | Leader |
|---|---|---|---|
| OTIS Mock AIME | 98.9% | 73.3% | Gemini 3.8 Flash |
| FrontierMath, tiers 1 to 3 | 68.4% | Not measured | Only Gemini 3.8 Flash measured |
| FrontierMath, tier 4 | 22.0% | Not measured | Only Gemini 3.8 Flash measured |
| ProofBench | 48.0% | Not measured | Only Gemini 3.8 Flash measured |
| LMArena Text: math | 1532 | 1463 | Gemini 3.8 Flash |
| LMArena Text: mathematical work | 1519 | 1465 | Gemini 3.8 Flash |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index70
| Benchmark | Gemini 3.8 Flash | Gemma 4 31B | Leader |
|---|---|---|---|
| MMLU Pro | 90.2% | Not measured | Only Gemini 3.8 Flash measured |
| LegalBench (Vals AI) | 87.0% | Not measured | Only Gemini 3.8 Flash measured |
| CaseLaw (Vals AI) | Not measured | 52.6% | Only Gemma 4 31B measured |
| TaxEval (Vals AI) | 74.5% | Not measured | Only Gemini 3.8 Flash measured |
| MortgageTax (Vals AI) | 65.3% | 61.4% | Gemini 3.8 Flash |
| MedCode (Vals AI) | 48.1% | Not measured | Only Gemini 3.8 Flash measured |
| SimpleQA Verified | 69.7% | 10.4% | Gemini 3.8 Flash |
| LMArena Text: science | 1523 | 1457 | Gemini 3.8 Flash |
| LMArena Text: medicine and healthcare | 1508 | 1451 | Gemini 3.8 Flash |
| LMArena Text: legal and government | 1497 | 1438 | Gemini 3.8 Flash |
| LMArena Text: business and finance | 1479 | 1430 | Gemini 3.8 Flash |
| FACTS Benchmark Suite | 69.4% | 45.3% | Gemini 3.8 Flash |
| Neither model has a result on the other 6 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Gemini 3.8 Flash | Gemma 4 31B | Leader |
|---|---|---|---|
| Design Arena: websites | 1300 | Not measured | Only Gemini 3.8 Flash measured |
| Design Arena: UI components | 1319 | Not measured | Only Gemini 3.8 Flash measured |
| Design Arena: game dev | 1305 | Not measured | Only Gemini 3.8 Flash measured |
| Design Arena: data viz | 1269 | Not measured | Only Gemini 3.8 Flash measured |
| Design Arena: 3D | 1295 | Not measured | Only Gemini 3.8 Flash measured |
| Design Arena: all code categories | 1304 | Not measured | Only Gemini 3.8 Flash measured |
| Design Arena: SVG | 1295 | Not measured | Only Gemini 3.8 Flash measured |
| Design Arena: ASCII art | 1265 | Not measured | Only Gemini 3.8 Flash measured |
| LiveBench design | 72.7% | 58.4% | Gemini 3.8 Flash |
GeneralLike-for-likePublic boards, shown as published, kept out of the index251
| Benchmark | Gemini 3.8 Flash | Gemma 4 31B | Leader |
|---|---|---|---|
| Vals Index | 56.0% | Not measured | Only Gemini 3.8 Flash measured |
| LiveBench data analysis | 54.0% | 53.3% | Gemini 3.8 Flash |
| Public Benefits Bench (Vals AI) | 65.3% | Not measured | Only Gemini 3.8 Flash measured |
| SAGE (Vals AI) | 35.1% | 55.0% | Gemma 4 31B |
| MedScribe (Vals AI) | 84.5% | Not measured | Only Gemini 3.8 Flash measured |
| IFBench | Not measured | 75.6% | Only Gemma 4 31B measured |
| Long context reasoning (AA-LCR) | 84.0% | 69.7% | Gemini 3.8 Flash |
| DTBench | 95.7% | 82.7% | Gemini 3.8 Flash |
| LMCA | 52.9% | 39.3% | Gemini 3.8 Flash |
| Surface Evolver Bench | 76.9% | 30.6% | Gemini 3.8 Flash |
| Furniture assembly | 31.7% | Not measured | Only Gemini 3.8 Flash measured |
| LMArena Text | 1499 | 1443 | Gemini 3.8 Flash |
| LMArena Text: instruction following | 1492 | 1433 | Gemini 3.8 Flash |
| LMArena Text: creative writing | 1488 | 1417 | Gemini 3.8 Flash |
| LMArena Vision | 1315 | 1276 | Gemini 3.8 Flash |
| LMArena Text: English | 1498 | 1451 | Gemini 3.8 Flash |
| LMArena Text: non-English | 1491 | 1430 | Gemini 3.8 Flash |
| LMArena Text: Chinese | 1553 | 1475 | Gemini 3.8 Flash |
| LMArena Text: German | 1501 | Not measured | Only Gemini 3.8 Flash measured |
| LMArena Text: Japanese | 1507 | Not measured | Only Gemini 3.8 Flash measured |
| LMArena Text: Korean | 1464 | Not measured | Only Gemini 3.8 Flash measured |
| LMArena Text: French | 1496 | 1436 | Gemini 3.8 Flash |
| LMArena Text: Spanish | 1487 | 1442 | Gemini 3.8 Flash |
| LMArena Text: Russian | 1514 | 1460 | Gemini 3.8 Flash |
| LMArena Text: Polish | 1497 | 1433 | Gemini 3.8 Flash |
| LMArena Text: multi-turn | 1503 | 1452 | Gemini 3.8 Flash |
| LMArena Text: longer queries | 1507 | 1446 | Gemini 3.8 Flash |
| LMArena Text: writing and language | 1494 | 1432 | Gemini 3.8 Flash |
| LMArena Text: entertainment and media | 1480 | 1405 | Gemini 3.8 Flash |
| LMArena Vision: English | 1318 | 1271 | Gemini 3.8 Flash |
| LMArena Vision: Chinese | 1416 | 1326 | Gemini 3.8 Flash |
| LMArena Vision: reading text | 1333 | 1282 | Gemini 3.8 Flash |
| LMArena Vision: humor | 1321 | 1280 | Gemini 3.8 Flash |
| LMArena Vision: captioning | Not measured | 1218 | Only Gemma 4 31B measured |
| LMArena Vision: recognizing things | Not measured | 1226 | Only Gemma 4 31B measured |
| LMArena Vision: creative writing | 1299 | 1285 | Gemini 3.8 Flash |
| LMArena Document | Not measured | 1425 | Only Gemma 4 31B measured |
| Neither model has a result on the other 9 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Gemini 3.8 Flash | Gemma 4 31B | 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
Gemma 4 31B costs less
Repository review
50K input + 3K output tokens
Gemma 4 31B costs less
Agent loop
200K input + 10K output tokens
Gemma 4 31B 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 3.8 Flash | Google Gemma 4 31B |
|---|---|---|
| Maker | ||
| Weights | No public weights listed | Open weights |
| Released | September 2, 2026 | April 2, 2026 |
| Context window | 1.05M | 262K |
| Input $/Mtok | $0.75 | $0.14 |
| Output $/Mtok | $3.75 | $0.40 |
| Coding index | 61.6 | 39.0 |
| Independent measurements behind it | 6 | 2 |
| Cost per solved task | $2.74 | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Gemini 3.8 Flash better than Gemma 4 31B for coding?
Pick Gemini 3.8 Flash for coding: it scores 61.6 on the Vibe Coding Index against 39.0 for Gemma 4 31B. Pick Gemma 4 31B for output tokens 9.4x cheaper ($0.40 vs $3.75 per million) and work measured by SAGE (Vals AI), where it leads.
Which is cheaper, Gemini 3.8 Flash or Gemma 4 31B?
Gemini 3.8 Flash costs $0.75 per million input tokens and $3.75 per million output tokens; Gemma 4 31B costs $0.14 and $0.40. Cost per solved task is known for Gemini 3.8 Flash only.
Which has the bigger context window, Gemini 3.8 Flash or Gemma 4 31B?
Gemini 3.8 Flash, with 1.05M tokens against 262K.
How many benchmarks is the Gemini 3.8 Flash vs Gemma 4 31B comparison based on?
63 benchmarks have a result for both models as of October 21, 2026. Gemini 3.8 Flash's coding index rests on 6 independent benchmarks and Gemma 4 31B's on 2. Where only one model has a result, the page says so instead of naming a winner.