Gemini 3 Flash Preview vs Kimi K2.5
Gemini 3 Flash Preview leads Kimi K2.5 on coding, 43.7 to 38.6 on the Vibe Coding Index, at about the same output price ($3.00 vs $2.85 per million). Updated October 22, 2026; 45 benchmarks have a result for both.
Gemini 3 Flash Preview or Kimi K2.5: which to pick
Pick Gemini 3 Flash Preview for coding: it scores 43.7 on the Vibe Coding Index against 38.6 for Kimi K2.5, though on 2 benchmarks against 3.
Pick Kimi K2.5 for output tokens 1.1x cheaper ($2.85 vs $3.00 per million) and a lower cost per solved task ($0.24 against $0.37).
- Shared results
- 45
- Gemini 3 Flash Preview only
- 26
- Kimi K2.5 only
- 54
- 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 Flash Preview
Gemini 3 Flash Preview scores 43.7 against 38.6.
2 and 3 benchmarks behind the scores
Intelligence
AA Intelligence Index
Gemini 3 Flash Preview
Gemini 3 Flash Preview leads, 26.3 against 23.5.
Same board, both measured
Reasoning
GPQA Diamond
Gemini 3 Flash Preview
Gemini 3 Flash Preview leads, 87.9% against 84.1%.
Same board, both measured
Math
AIME
No call
Tied at 95.6%.
Same board, both measured
Knowledge
MMLU Pro
Gemini 3 Flash Preview
Gemini 3 Flash Preview leads, 88.6% against 85.9%.
Same board, both measured
Web design
Design Arena: websites
Kimi K2.5
Kimi K2.5 leads, 1248 against 1196.
Same board, both measured
Long documents
Listed context window
Gemini 3 Flash Preview
Gemini 3 Flash Preview takes 1.05M tokens against 262K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Kimi K2.5
Gemini 3 Flash Preview $0.0020, Kimi K2.5 $0.0020 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
Kimi K2.5
Gemini 3 Flash Preview $0.37, Kimi K2.5 $0.24.
Published attempt cost and pass rate
At a glance
- Coding index
- Gemini 3 Flash Preview 43.7 from 2 benchmarks, Kimi K2.5 38.6 from 3 benchmarks.
- Widest category
- Reasoning, 10.0 points apart on average over 7 shared benchmarks.
- Widest single gap
- SimpleQA Verified: Gemini 3 Flash Preview 66.8% against Kimi K2.5 34.3%, 32.5 points apart on a 0 to 100 scale.
- Output price
- Gemini 3 Flash Preview $3.00 against Kimi K2.5 $2.85 per million output tokens, 1.1x apart.
- Context window
- Gemini 3 Flash Preview takes 1.05M tokens, Kimi K2.5 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 Flash Preview | Bars | Kimi K2.5 | Ties |
|---|---|---|---|---|
| Coding | 9 | 1 | ||
| Intelligence | 1 | 0 | ||
| Agentic work | 3 | 7 | ||
| Reasoning | 7 | 0 | ||
| Math | 0 | 0 | 1 tie | |
| Knowledge | 5 | 3 | ||
| Web design | 0 | 4 | ||
| General | 2 | 1 | 1 tie | |
| All shared boards | 27 | 16 | 2 ties |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index91
| Benchmark | Gemini 3 Flash Preview | Kimi K2.5 | Leader |
|---|---|---|---|
| SWE-bench Verified | 75.8% | 70.8% | Gemini 3 Flash Preview |
| SWE-bench Multilingual | Not measured | 67.3% | Only Kimi K2.5 measured |
| LMArena WebDev | Not measured | 1437 | Only Kimi K2.5 measured |
| AA Coding Index | Not measured | 46.8 | Only Kimi K2.5 measured |
| LiveCodeBench (Vals AI) | 85.6% | 83.9% | Gemini 3 Flash Preview |
| SWE-bench Verified (Vals AI) | 75.0% | 70.0% | Gemini 3 Flash Preview |
| Vibe Code Bench (Vals AI) | 20.2% | 17.5% | Gemini 3 Flash Preview |
| Code migration (Vals AI) | 6.4% | 7.0% | Kimi K2.5 |
| ProgramBench (Vals AI) | 0.0% | Not measured | Only Gemini 3 Flash Preview measured |
| Terminal-Bench 2.1 (Vals AI) | 53.9% | 42.0% | Gemini 3 Flash Preview |
| LiveCodeBench (Artificial Analysis run) | 90.8% | Not measured | Only Gemini 3 Flash Preview measured |
| Terminal-Bench Hard (Artificial Analysis run) | 38.6% | 34.8% | Gemini 3 Flash Preview |
| Terminal-Bench | 64.3% | 43.2% | Gemini 3 Flash Preview |
| GSO-Bench | 9.8% | Not measured | Only Gemini 3 Flash Preview measured |
| WeirdML | 61.6% | 45.6% | Gemini 3 Flash Preview |
| ALE-Bench | 1367.2 | 821.6 | Gemini 3 Flash Preview |
| LMArena Text: coding | Not measured | 1483 | Only Kimi K2.5 measured |
| LMArena Text: software and IT | Not measured | 1471 | Only Kimi K2.5 measured |
| LMArena WebDev: React | Not measured | 1429 | Only Kimi K2.5 measured |
| LMArena WebDev: HTML | Not measured | 1426 | Only Kimi K2.5 measured |
| LMArena WebDev: from an image | Not measured | 1439 | Only Kimi K2.5 measured |
| SciCode | 12.7% | Not measured | Only Gemini 3 Flash Preview measured |
| Neither model has a result on the other 17 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Gemini 3 Flash Preview | Kimi K2.5 | Leader |
|---|---|---|---|
| AA Intelligence Index | 26.3 | 23.5 | Gemini 3 Flash Preview |
| Epoch Capabilities Index | Not measured | 148.1 | Only Kimi K2.5 measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index37
| Benchmark | Gemini 3 Flash Preview | Kimi K2.5 | Leader |
|---|---|---|---|
| Design Arena: agents building web apps | 1111 | 1136 | Kimi K2.5 |
| Design Arena: agents building full-stack apps | 1063 | 1114 | Kimi K2.5 |
| Design Arena: agents building mobile apps | 1090 | 1147 | Kimi K2.5 |
| Design Arena: agents building Android apps | 1051 | 1118 | Kimi K2.5 |
| Design Arena: agents building Godot games | 1161 | 1219 | Kimi K2.5 |
| Design Arena: PowerPoint slides | 1036 | Not measured | Only Gemini 3 Flash Preview measured |
| Finance Agent (Vals AI) | 42.5% | 35.8% | Gemini 3 Flash Preview |
| Tax Agent Bench (Vals AI) | 11.8% | Not measured | Only Gemini 3 Flash Preview measured |
| Legal Research Bench (Vals AI) | 18.3% | 15.9% | Gemini 3 Flash Preview |
| Excel Modeling Benchmark (Vals AI) | 26.0% | 28.5% | Kimi K2.5 |
| τ²-Bench Telecom | 80.4% | 95.9% | Kimi K2.5 |
| BALROG | 48.1% | Not measured | Only Gemini 3 Flash Preview measured |
| DeepResearch Bench | 49.8% | Not measured | Only Gemini 3 Flash Preview measured |
| OSWorld | Not measured | 63.3% | Only Kimi K2.5 measured |
| Vending-Bench 2 | $3,635 | $1,198 | Gemini 3 Flash Preview |
| Neither model has a result on the other 26 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index70
| Benchmark | Gemini 3 Flash Preview | Kimi K2.5 | Leader |
|---|---|---|---|
| GPQA Diamond | 87.9% | 84.1% | Gemini 3 Flash Preview |
| MMMU Pro (Vals AI) | 87.6% | 84.3% | Gemini 3 Flash Preview |
| GPQA Diamond (Artificial Analysis run) | 89.8% | 87.9% | Gemini 3 Flash Preview |
| Humanity's Last Exam (Artificial Analysis run) | 36.6% | 30.7% | Gemini 3 Flash Preview |
| GPQA Diamond (Epoch AI run) | 89.4% | Not measured | Only Gemini 3 Flash Preview measured |
| ARC-AGI | 84.7% | 65.3% | Gemini 3 Flash Preview |
| ARC-AGI-2 | 33.6% | 11.8% | Gemini 3 Flash Preview |
| SimpleBench | 61.1% | 46.8% | Gemini 3 Flash Preview |
| Chess puzzles | 39.0% | Not measured | Only Gemini 3 Flash Preview measured |
| Mystery game puzzles | 26.0% | Not measured | Only Gemini 3 Flash Preview measured |
| VPCT | 72.6% | Not measured | Only Gemini 3 Flash Preview measured |
| LMArena Text: hard prompts | Not measured | 1453 | Only Kimi K2.5 measured |
| LMArena Text: expert | Not measured | 1466 | Only Kimi K2.5 measured |
| LMArena Text: hard prompts in English | Not measured | 1460 | Only Kimi K2.5 measured |
| LMArena Vision: diagrams | Not measured | 1282 | Only Kimi K2.5 measured |
| LMArena Vision: homework | Not measured | 1297 | Only Kimi K2.5 measured |
| Kagi LLM Benchmark | Not measured | 78.5% | Only Kimi K2.5 measured |
| Neither model has a result on the other 5 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index00
| Benchmark | Gemini 3 Flash Preview | Kimi K2.5 | Leader |
|---|---|---|---|
| AIME | 95.6% | 95.6% | Tie |
| MGSM (Vals AI) | 93.3% | Not measured | Only Gemini 3 Flash Preview measured |
| AA Math Index | 97.0 | Not measured | Only Gemini 3 Flash Preview measured |
| AIME 2025 (Artificial Analysis run) | 97.0% | Not measured | Only Gemini 3 Flash Preview measured |
| OTIS Mock AIME | 95.6% | Not measured | Only Gemini 3 Flash Preview measured |
| FrontierMath, tiers 1 to 3 | 51.2% | Not measured | Only Gemini 3 Flash Preview measured |
| FrontierMath, tier 4 | 17.1% | Not measured | Only Gemini 3 Flash Preview measured |
| ProofBench | 15.0% | Not measured | Only Gemini 3 Flash Preview measured |
| LMArena Text: math | Not measured | 1470 | Only Kimi K2.5 measured |
| LMArena Text: mathematical work | Not measured | 1473 | Only Kimi K2.5 measured |
| Neither model has a result on the other 3 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index53
| Benchmark | Gemini 3 Flash Preview | Kimi K2.5 | Leader |
|---|---|---|---|
| MMLU Pro | 88.6% | 85.9% | Gemini 3 Flash Preview |
| LegalBench (Vals AI) | 86.9% | Not measured | Only Gemini 3 Flash Preview measured |
| CaseLaw (Vals AI) | 55.8% | 58.7% | Kimi K2.5 |
| CorpFin (Vals AI) | 66.4% | 68.3% | Kimi K2.5 |
| TaxEval (Vals AI) | 73.9% | 74.2% | Kimi K2.5 |
| MortgageTax (Vals AI) | 68.7% | 66.5% | Gemini 3 Flash Preview |
| MedQA (Vals AI) | 95.8% | 94.4% | Gemini 3 Flash Preview |
| MedCode (Vals AI) | 55.9% | 39.3% | Gemini 3 Flash Preview |
| MMLU Pro (Artificial Analysis run) | 89.0% | Not measured | Only Gemini 3 Flash Preview measured |
| SimpleQA Verified | 66.8% | 34.3% | Gemini 3 Flash Preview |
| GeoBench | 88.0% | Not measured | Only Gemini 3 Flash Preview measured |
| LMArena Text: science | Not measured | 1459 | Only Kimi K2.5 measured |
| LMArena Text: medicine and healthcare | Not measured | 1448 | Only Kimi K2.5 measured |
| LMArena Text: legal and government | Not measured | 1441 | Only Kimi K2.5 measured |
| LMArena Text: business and finance | Not measured | 1427 | Only Kimi K2.5 measured |
| FACTS Benchmark Suite | 63.4% | Not measured | Only Gemini 3 Flash Preview measured |
| Neither model has a result on the other 2 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index04
| Benchmark | Gemini 3 Flash Preview | Kimi K2.5 | Leader |
|---|---|---|---|
| Design Arena: websites | 1196 | 1248 | Kimi K2.5 |
| Design Arena: UI components | Not measured | 1234 | Only Kimi K2.5 measured |
| Design Arena: game dev | 1166 | 1206 | Kimi K2.5 |
| Design Arena: data viz | Not measured | 1219 | Only Kimi K2.5 measured |
| Design Arena: 3D | 1183 | 1204 | Kimi K2.5 |
| Design Arena: all code categories | 1189 | 1236 | Kimi K2.5 |
| Design Arena: SVG | Not measured | 1149 | Only Kimi K2.5 measured |
| Design Arena: ASCII art | Not measured | 1166 | Only Kimi K2.5 measured |
| Neither model has a result on the other 1 board here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index21
| Benchmark | Gemini 3 Flash Preview | Kimi K2.5 | Leader |
|---|---|---|---|
| SAGE (Vals AI) | 51.8% | 49.9% | Gemini 3 Flash Preview |
| MedScribe (Vals AI) | 69.9% | 76.4% | Kimi K2.5 |
| Vals Multimodal Index | 52.2% | Not measured | Only Gemini 3 Flash Preview measured |
| IFBench | 78.0% | 70.2% | Gemini 3 Flash Preview |
| Long context reasoning (AA-LCR) | 78.0% | 78.0% | Tie |
| DTBench | 89.1% | Not measured | Only Gemini 3 Flash Preview measured |
| LMCA | 43.1% | Not measured | Only Gemini 3 Flash Preview measured |
| Fiction.LiveBench | Not measured | 86.1% | Only Kimi K2.5 measured |
| CL-bench | Not measured | 19.3% | Only Kimi K2.5 measured |
| CL-bench Life | Not measured | 13.2% | Only Kimi K2.5 measured |
| LMArena Text | Not measured | 1445 | Only Kimi K2.5 measured |
| LMArena Text: instruction following | Not measured | 1431 | Only Kimi K2.5 measured |
| LMArena Text: creative writing | Not measured | 1422 | Only Kimi K2.5 measured |
| LMArena Vision | Not measured | 1269 | Only Kimi K2.5 measured |
| LMArena Text: English | Not measured | 1453 | Only Kimi K2.5 measured |
| LMArena Text: non-English | Not measured | 1433 | Only Kimi K2.5 measured |
| LMArena Text: Chinese | Not measured | 1494 | Only Kimi K2.5 measured |
| LMArena Text: German | Not measured | 1441 | Only Kimi K2.5 measured |
| LMArena Text: Japanese | Not measured | 1423 | Only Kimi K2.5 measured |
| LMArena Text: Korean | Not measured | 1412 | Only Kimi K2.5 measured |
| LMArena Text: French | Not measured | 1454 | Only Kimi K2.5 measured |
| LMArena Text: Spanish | Not measured | 1450 | Only Kimi K2.5 measured |
| LMArena Text: Russian | Not measured | 1435 | Only Kimi K2.5 measured |
| LMArena Text: Polish | Not measured | 1445 | Only Kimi K2.5 measured |
| LMArena Text: multi-turn | Not measured | 1444 | Only Kimi K2.5 measured |
| LMArena Text: longer queries | Not measured | 1445 | Only Kimi K2.5 measured |
| LMArena Text: writing and language | Not measured | 1425 | Only Kimi K2.5 measured |
| LMArena Text: entertainment and media | Not measured | 1417 | Only Kimi K2.5 measured |
| LMArena Vision: English | Not measured | 1274 | Only Kimi K2.5 measured |
| LMArena Vision: Chinese | Not measured | 1328 | Only Kimi K2.5 measured |
| LMArena Vision: reading text | Not measured | 1276 | Only Kimi K2.5 measured |
| LMArena Vision: humor | Not measured | 1284 | Only Kimi K2.5 measured |
| LMArena Vision: captioning | Not measured | 1257 | Only Kimi K2.5 measured |
| LMArena Vision: recognizing things | Not measured | 1285 | Only Kimi K2.5 measured |
| LMArena Vision: creative writing | Not measured | 1269 | Only Kimi K2.5 measured |
| Neither model has a result on the other 11 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Gemini 3 Flash Preview | Kimi K2.5 | 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
Kimi K2.5 costs less
Repository review
50K input + 3K output tokens
Gemini 3 Flash Preview costs less
Agent loop
200K input + 10K output tokens
Gemini 3 Flash Preview 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 Flash Preview | MoonshotAI Kimi K2.5 |
|---|---|---|
| Maker | Moonshot AI | |
| Weights | No public weights listed | Open weights |
| Released | December 17, 2025 | January 27, 2026 |
| Context window | 1.05M | 262K |
| Input $/Mtok | $0.50 | $0.532 |
| Output $/Mtok | $3.00 | $2.85 |
| Coding index | 43.7 | 38.6 |
| Independent measurements behind it | 2 | 3 |
| Cost per solved task | $0.37 | $0.24 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Gemini 3 Flash Preview better than Kimi K2.5 for coding?
Pick Gemini 3 Flash Preview for coding: it scores 43.7 on the Vibe Coding Index against 38.6 for Kimi K2.5, though on 2 benchmarks against 3. Pick Kimi K2.5 for output tokens 1.1x cheaper ($2.85 vs $3.00 per million) and a lower cost per solved task ($0.24 against $0.37).
Which is cheaper, Gemini 3 Flash Preview or Kimi K2.5?
Gemini 3 Flash Preview costs $0.50 per million input tokens and $3.00 per million output tokens; Kimi K2.5 costs $0.532 and $2.85. Per solved SWE-bench Verified task, Gemini 3 Flash Preview costs $0.37 and Kimi K2.5 $0.24.
Which has the bigger context window, Gemini 3 Flash Preview or Kimi K2.5?
Gemini 3 Flash Preview, with 1.05M tokens against 262K.
How many benchmarks is the Gemini 3 Flash Preview vs Kimi K2.5 comparison based on?
45 benchmarks have a result for both models as of October 22, 2026. Gemini 3 Flash Preview's coding index rests on 2 independent benchmarks and Kimi K2.5's on 3. Where only one model has a result, the page says so instead of naming a winner.