GPT-5.5 vs MiMo-V2.6-Flash
Updated October 21, 2026. 57 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
Decision reading
Pick GPT-5.5 for coding: it scores 67.8 on the Vibe Coding Index against 61.9 for MiMo-V2.6-Flash.
Pick MiMo-V2.6-Flash when output tokens cost 107.1x less, or when what matters is LMArena WebDev or Vibe Code Bench (Vals AI), where it leads.
- Shared results
- 57
- GPT-5.5 only
- 75
- MiMo-V2.6-Flash only
- 9
- Like-for-like categories
- 7 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
GPT-5.5
GPT-5.5 scores 67.8 against 61.9.
2 and 1 benchmarks behind the scores
Intelligence
AA Intelligence Index
GPT-5.5
GPT-5.5 leads, 38.4 against 37.9.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only GPT-5.5 has a AA Agentic Index result, 36.4.
Directional only
Reasoning
GPQA Diamond
No call
Only GPT-5.5 has a GPQA Diamond result, 93.2%.
Directional only
Knowledge
MMLU Pro
No call
Only GPT-5.5 has a MMLU Pro result, 88.1%.
Directional only
Web design
Design Arena: websites
No call
Only GPT-5.5 has a Design Arena: websites result, 1256.
Directional only
General
Vals Index
No call
Only MiMo-V2.6-Flash has a Vals Index result, 54.8%.
Directional only
Long documents
Listed context window
No call
Both take 1.05M tokens.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
MiMo-V2.6-Flash
GPT-5.5 $0.020, MiMo-V2.6-Flash $0.0003 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only GPT-5.5 has the number, $1.65.
Directional only
At a glance
- Coding index
- GPT-5.5 67.8 from 2 benchmarks, MiMo-V2.6-Flash 61.9 from 1 benchmark.
- Widest category
- Coding, 8.0 points apart on average over 12 shared benchmarks.
- Widest single gap
- LMArena Text: Japanese: GPT-5.5 1499 against MiMo-V2.6-Flash 1359, 23.3 points apart on a 0 to 100 scale.
- Output price
- GPT-5.5 $30.00 against MiMo-V2.6-Flash $0.28 per million output tokens, 107.1x apart.
- Context window
- Both take 1.05M tokens.
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 | GPT-5.5 | Bars | MiMo-V2.6-Flash | Ties |
|---|---|---|---|---|
| Coding | 3 | 7 | 2 ties | |
| Intelligence | 1 | 0 | ||
| Agentic work | 1 | 4 | ||
| Reasoning | 5 | 1 | ||
| Math | 2 | 1 | ||
| Knowledge | 5 | 0 | ||
| General | 23 | 2 | ||
| All shared boards | 40 | 15 | 2 ties |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index37
| Benchmark | GPT-5.5 | MiMo-V2.6-Flash | Leader |
|---|---|---|---|
| LiveBench coding | 85.1% | Not measured | Only GPT-5.5 measured |
| LMArena WebDev | 1513 | 1634 | MiMo-V2.6-Flash |
| AA Coding Index | 74.9 | Not measured | Only GPT-5.5 measured |
| LiveCodeBench (Vals AI) | 85.3% | Not measured | Only GPT-5.5 measured |
| SWE-bench Verified (Vals AI) | 82.6% | Not measured | Only GPT-5.5 measured |
| Terminal-Bench 4 (Vals AI) | Not measured | 24.2% | Only MiMo-V2.6-Flash measured |
| Vibe Code Bench (Vals AI) | 69.8% | 79.0% | MiMo-V2.6-Flash |
| Code migration (Vals AI) | 45.2% | 40.9% | GPT-5.5 |
| ProgramBench (Vals AI) | 0.5% | 0.5% | Tie |
| IOI (Vals AI) | Not measured | 47.7% | Only MiMo-V2.6-Flash measured |
| Terminal-Bench 2.1 (Vals AI) | 76.4% | 76.4% | Tie |
| SkillsBench (Vals AI) | 62.5% | Not measured | Only GPT-5.5 measured |
| CyberBench (Vals AI) | Not measured | 75.4% | Only MiMo-V2.6-Flash measured |
| SciCode | 56.1% | 51.3% | GPT-5.5 |
| Terminal-Bench Hard (Artificial Analysis run) | 60.6% | Not measured | Only GPT-5.5 measured |
| Terminal-Bench | 84.7% | Not measured | Only GPT-5.5 measured |
| FrontierCode | 43.0% | Not measured | Only GPT-5.5 measured |
| GSO-Bench | 40.2% | Not measured | Only GPT-5.5 measured |
| WeirdML | 84.9% | Not measured | Only GPT-5.5 measured |
| MirrorCode | 10.0% | Not measured | Only GPT-5.5 measured |
| ALE-Bench | 1943.0 | 1244.2 | GPT-5.5 |
| LMArena Text: coding | 1494 | 1499 | MiMo-V2.6-Flash |
| LMArena Text: software and IT | 1493 | 1497 | MiMo-V2.6-Flash |
| LMArena WebDev: React | 1506 | 1648 | MiMo-V2.6-Flash |
| LMArena WebDev: HTML | 1543 | 1641 | MiMo-V2.6-Flash |
| LMArena WebDev: from an image | 1532 | 1596 | MiMo-V2.6-Flash |
| Neither model has a result on the other 12 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | GPT-5.5 | MiMo-V2.6-Flash | Leader |
|---|---|---|---|
| AA Intelligence Index | 38.4 | 37.9 | GPT-5.5 |
| Epoch Capabilities Index | 159.7 | Not measured | Only GPT-5.5 measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index14
| Benchmark | GPT-5.5 | MiMo-V2.6-Flash | Leader |
|---|---|---|---|
| AA Agentic Index | 36.4 | Not measured | Only GPT-5.5 measured |
| Design Arena: agents building web apps | 1117 | Not measured | Only GPT-5.5 measured |
| Design Arena: agents building full-stack apps | 1089 | Not measured | Only GPT-5.5 measured |
| Design Arena: agents building mobile apps | 1143 | Not measured | Only GPT-5.5 measured |
| Design Arena: agents building Android apps | 1169 | Not measured | Only GPT-5.5 measured |
| Design Arena: agents building Godot games | 1173 | Not measured | Only GPT-5.5 measured |
| Design Arena: agents building games | 1179 | Not measured | Only GPT-5.5 measured |
| Design Arena: HTML slides | 1067 | Not measured | Only GPT-5.5 measured |
| Design Arena: PowerPoint slides | 1108 | Not measured | Only GPT-5.5 measured |
| LiveBench research | 61.6% | Not measured | Only GPT-5.5 measured |
| LiveBench browser | 48.0% | Not measured | Only GPT-5.5 measured |
| LiveBench long agentic | 44.6% | Not measured | Only GPT-5.5 measured |
| SREBench (Vals AI) | 3.8% | 4.2% | MiMo-V2.6-Flash |
| Finance Agent (Vals AI) | 51.8% | 56.3% | MiMo-V2.6-Flash |
| Tax Agent Bench (Vals AI) | 21.8% | 28.5% | MiMo-V2.6-Flash |
| Legal Research Bench (Vals AI) | 40.4% | 38.0% | GPT-5.5 |
| Harvey's Legal Agent Benchmark (Vals AI) | Not measured | 13.3% | Only MiMo-V2.6-Flash measured |
| Excel Modeling Benchmark (Vals AI) | 64.5% | 65.5% | MiMo-V2.6-Flash |
| BioMysteryBench (Vals AI) | Not measured | 69.3% | Only MiMo-V2.6-Flash measured |
| Terminal-Bench-Science (Vals AI) | Not measured | 4.3% | Only MiMo-V2.6-Flash measured |
| Vals Science Index | Not measured | 31.7% | Only MiMo-V2.6-Flash measured |
| Time Horizon Index (Vals AI) | 8.3% | Not measured | Only GPT-5.5 measured |
| τ²-Bench Telecom | 93.9% | Not measured | Only GPT-5.5 measured |
| APEX-Agents | 55.1% | Not measured | Only GPT-5.5 measured |
| Remote Labor Index | 6.3% | Not measured | Only GPT-5.5 measured |
| OSWorld 2.0 | 13.0% | Not measured | Only GPT-5.5 measured |
| DeepResearch Bench | 54.0% | Not measured | Only GPT-5.5 measured |
| PostTrainBench | 27.2% | Not measured | Only GPT-5.5 measured |
| Vending-Bench 2 | $7,524 | Not measured | Only GPT-5.5 measured |
| Neither model has a result on the other 10 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index51
| Benchmark | GPT-5.5 | MiMo-V2.6-Flash | Leader |
|---|---|---|---|
| GPQA Diamond | 93.2% | Not measured | Only GPT-5.5 measured |
| LiveBench reasoning | 89.7% | Not measured | Only GPT-5.5 measured |
| MysteryMechanism (Vals AI) | Not measured | 21.6% | Only MiMo-V2.6-Flash measured |
| MMMU Pro (Vals AI) | 88.3% | Not measured | Only GPT-5.5 measured |
| GPQA Diamond (Artificial Analysis run) | 93.5% | Not measured | Only GPT-5.5 measured |
| Humanity's Last Exam (Artificial Analysis run) | 45.8% | 35.1% | GPT-5.5 |
| GPQA Diamond (Epoch AI run) | 90.7% | Not measured | Only GPT-5.5 measured |
| ARC-AGI | 95.0% | Not measured | Only GPT-5.5 measured |
| ARC-AGI-2 | 85.0% | Not measured | Only GPT-5.5 measured |
| SimpleBench | 69.0% | Not measured | Only GPT-5.5 measured |
| Chess puzzles | 63.0% | Not measured | Only GPT-5.5 measured |
| Mystery game puzzles | 56.0% | Not measured | Only GPT-5.5 measured |
| EBR-bench | 34.3% | Not measured | Only GPT-5.5 measured |
| LMArena Text: hard prompts | 1489 | 1475 | GPT-5.5 |
| LMArena Text: expert | 1507 | 1496 | GPT-5.5 |
| LMArena Text: hard prompts in English | 1483 | 1493 | MiMo-V2.6-Flash |
| LMArena Vision: diagrams | 1325 | 1276 | GPT-5.5 |
| LMArena Vision: homework | 1332 | 1283 | GPT-5.5 |
| Neither model has a result on the other 3 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index21
| Benchmark | GPT-5.5 | MiMo-V2.6-Flash | Leader |
|---|---|---|---|
| OTIS Mock AIME | 84.4% | Not measured | Only GPT-5.5 measured |
| FrontierMath, tiers 1 to 3 | 85.3% | Not measured | Only GPT-5.5 measured |
| FrontierMath, tier 4 | 72.5% | Not measured | Only GPT-5.5 measured |
| ProofBench | 50.0% | 63.0% | MiMo-V2.6-Flash |
| LMArena Text: math | 1487 | 1476 | GPT-5.5 |
| LMArena Text: mathematical work | 1496 | 1478 | GPT-5.5 |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index50
| Benchmark | GPT-5.5 | MiMo-V2.6-Flash | Leader |
|---|---|---|---|
| MMLU Pro | 88.1% | Not measured | Only GPT-5.5 measured |
| LegalBench (Vals AI) | 86.5% | Not measured | Only GPT-5.5 measured |
| CaseLaw (Vals AI) | 66.2% | Not measured | Only GPT-5.5 measured |
| CorpFin (Vals AI) | 68.4% | Not measured | Only GPT-5.5 measured |
| TaxEval (Vals AI) | 75.0% | Not measured | Only GPT-5.5 measured |
| MortgageTax (Vals AI) | 68.8% | Not measured | Only GPT-5.5 measured |
| MedCode (Vals AI) | 49.1% | 41.1% | GPT-5.5 |
| SimpleQA Verified | 63.0% | Not measured | Only GPT-5.5 measured |
| LMArena Text: science | 1485 | 1462 | GPT-5.5 |
| LMArena Text: medicine and healthcare | 1465 | 1439 | GPT-5.5 |
| LMArena Text: legal and government | 1491 | 1441 | GPT-5.5 |
| LMArena Text: business and finance | 1478 | 1454 | GPT-5.5 |
| Neither model has a result on the other 5 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index9 boards, none shared
| Benchmark | GPT-5.5 | MiMo-V2.6-Flash | Leader |
|---|---|---|---|
| Design Arena: websites | 1256 | Not measured | Only GPT-5.5 measured |
| Design Arena: UI components | 1260 | Not measured | Only GPT-5.5 measured |
| Design Arena: game dev | 1294 | Not measured | Only GPT-5.5 measured |
| Design Arena: data viz | 1265 | Not measured | Only GPT-5.5 measured |
| Design Arena: 3D | 1198 | Not measured | Only GPT-5.5 measured |
| Design Arena: all code categories | 1260 | Not measured | Only GPT-5.5 measured |
| Design Arena: SVG | 1234 | Not measured | Only GPT-5.5 measured |
| Design Arena: ASCII art | 1254 | Not measured | Only GPT-5.5 measured |
| LiveBench design | 70.3% | Not measured | Only GPT-5.5 measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index232
| Benchmark | GPT-5.5 | MiMo-V2.6-Flash | Leader |
|---|---|---|---|
| Vals Index | Not measured | 54.8% | Only MiMo-V2.6-Flash measured |
| LiveBench data analysis | 81.6% | Not measured | Only GPT-5.5 measured |
| Public Benefits Bench (Vals AI) | 60.9% | 67.6% | MiMo-V2.6-Flash |
| SAGE (Vals AI) | 51.5% | 43.5% | GPT-5.5 |
| MedScribe (Vals AI) | 86.9% | 85.3% | GPT-5.5 |
| Vals Multimodal Index | 68.1% | Not measured | Only GPT-5.5 measured |
| IFBench | 75.9% | Not measured | Only GPT-5.5 measured |
| Long context reasoning (AA-LCR) | 84.3% | 74.3% | GPT-5.5 |
| DTBench | 96.0% | Not measured | Only GPT-5.5 measured |
| LMCA | 54.3% | Not measured | Only GPT-5.5 measured |
| Surface Evolver Bench | 88.1% | Not measured | Only GPT-5.5 measured |
| Furniture assembly | 44.2% | Not measured | Only GPT-5.5 measured |
| ExploitBench | 47.4% | Not measured | Only GPT-5.5 measured |
| CL-bench Life | 22.2% | Not measured | Only GPT-5.5 measured |
| LMArena Text | 1471 | 1453 | GPT-5.5 |
| LMArena Text: instruction following | 1478 | 1452 | GPT-5.5 |
| LMArena Text: creative writing | 1455 | 1403 | GPT-5.5 |
| LMArena Vision | 1297 | 1256 | GPT-5.5 |
| LMArena Text: English | 1470 | 1476 | MiMo-V2.6-Flash |
| LMArena Text: non-English | 1467 | 1431 | GPT-5.5 |
| LMArena Text: Chinese | 1534 | 1509 | GPT-5.5 |
| LMArena Text: German | 1480 | 1458 | GPT-5.5 |
| LMArena Text: Japanese | 1499 | 1359 | GPT-5.5 |
| LMArena Text: Korean | 1460 | 1425 | GPT-5.5 |
| LMArena Text: French | 1485 | 1480 | GPT-5.5 |
| LMArena Text: Spanish | 1468 | 1453 | GPT-5.5 |
| LMArena Text: Russian | 1473 | 1409 | GPT-5.5 |
| LMArena Text: Polish | 1465 | 1455 | GPT-5.5 |
| LMArena Text: multi-turn | 1476 | 1447 | GPT-5.5 |
| LMArena Text: longer queries | 1484 | 1459 | GPT-5.5 |
| LMArena Text: writing and language | 1466 | 1424 | GPT-5.5 |
| LMArena Text: entertainment and media | 1449 | 1415 | GPT-5.5 |
| LMArena Vision: English | 1292 | 1269 | GPT-5.5 |
| LMArena Vision: Chinese | 1360 | Not measured | Only GPT-5.5 measured |
| LMArena Vision: reading text | 1306 | 1270 | GPT-5.5 |
| LMArena Vision: humor | 1293 | Not measured | Only GPT-5.5 measured |
| LMArena Vision: recognizing things | 1231 | Not measured | Only GPT-5.5 measured |
| LMArena Vision: creative writing | 1301 | 1231 | GPT-5.5 |
| LMArena Document | 1486 | Not measured | Only GPT-5.5 measured |
| Neither model has a result on the other 7 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | GPT-5.5 | MiMo-V2.6-Flash | 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
MiMo-V2.6-Flash costs less
Repository review
50K input + 3K output tokens
MiMo-V2.6-Flash costs less
Agent loop
200K input + 10K output tokens
MiMo-V2.6-Flash 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 | OpenAI GPT-5.5 | Xiaomi MiMo-V2.6-Flash |
|---|---|---|
| Maker | OpenAI | Xiaomi |
| Weights | No public weights listed | Open weights |
| Released | April 24, 2026 | September 21, 2026 |
| Context window | 1.05M | 1.05M |
| Input $/Mtok | $5.00 | $0.14 |
| Output $/Mtok | $30.00 | $0.28 |
| Coding index | 67.8 | 61.9 |
| Independent measurements behind it | 2 | 1 |
| Cost per solved task | $1.65 | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is GPT-5.5 better than MiMo-V2.6-Flash for coding?
Pick GPT-5.5 for coding: it scores 67.8 on the Vibe Coding Index against 61.9 for MiMo-V2.6-Flash. Pick MiMo-V2.6-Flash when output tokens cost 107.1x less, or when what matters is LMArena WebDev or Vibe Code Bench (Vals AI), where it leads.
Which is cheaper, GPT-5.5 or MiMo-V2.6-Flash?
GPT-5.5 costs $5.00 per million input tokens and $30.00 per million output tokens; MiMo-V2.6-Flash costs $0.14 and $0.28. Cost per solved task is known for GPT-5.5 only.
Which has the bigger context window, GPT-5.5 or MiMo-V2.6-Flash?
Neither: both take 1.05M tokens.
How many benchmarks is the GPT-5.5 vs MiMo-V2.6-Flash comparison based on?
57 benchmarks have a result for both models as of October 21, 2026. GPT-5.5's coding index rests on 2 independent benchmarks and MiMo-V2.6-Flash's on 1. Where only one model has a result, the page says so instead of naming a winner.