GPT-6 Sol vs Mistral Medium 3.5
GPT-6 Sol leads Mistral Medium 3.5 on coding, 76.0 to 25.5 on the Vibe Coding Index, and Mistral Medium 3.5 costs 1.3x less per output token ($7.50 vs $10.00 per million). Updated October 21, 2026; 63 benchmarks have a result for both.
GPT-6 Sol or Mistral Medium 3.5: which to pick
Pick GPT-6 Sol for coding: it scores 76.0 on the Vibe Coding Index against 25.5 for Mistral Medium 3.5.
Pick Mistral Medium 3.5 for output tokens 1.3x cheaper ($7.50 vs $10.00 per million) and work measured by LMArena Text: coding or LMArena Text: software and IT, where it leads.
- Shared results
- 63
- GPT-6 Sol only
- 38
- Mistral Medium 3.5 only
- 18
- 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
GPT-6 Sol
GPT-6 Sol scores 76.0 against 25.5.
5 and 3 benchmarks behind the scores
Intelligence
AA Intelligence Index
GPT-6 Sol
GPT-6 Sol leads, 47.6 against 14.2.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only Mistral Medium 3.5 has a AA Agentic Index result, 7.0.
Directional only
Reasoning
GPQA Diamond
No call
Only Mistral Medium 3.5 has a GPQA Diamond result, 34.9%.
Directional only
Knowledge
MMLU Pro
No call
Only Mistral Medium 3.5 has a MMLU Pro result, 75.3%.
Directional only
Web design
Design Arena: websites
GPT-6 Sol
GPT-6 Sol leads, 1292 against 1142.
Same board, both measured
Long documents
Listed context window
GPT-6 Sol
GPT-6 Sol takes 1.05M tokens against 262K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Mistral Medium 3.5
GPT-6 Sol $0.0070, Mistral Medium 3.5 $0.0053 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Mistral Medium 3.5 has the number, $6.02.
Directional only
At a glance
- Coding index
- GPT-6 Sol 76.0 from 5 benchmarks, Mistral Medium 3.5 25.5 from 3 benchmarks.
- Widest category
- Coding, 42.8 points apart on average over 10 shared benchmarks.
- Widest single gap
- Vibe Code Bench (Vals AI): GPT-6 Sol 87.8% against Mistral Medium 3.5 2.9%, 84.9 points apart on a 0 to 100 scale.
- Output price
- GPT-6 Sol $10.00 against Mistral Medium 3.5 $7.50 per million output tokens, 1.3x apart.
- Context window
- GPT-6 Sol takes 1.05M tokens, Mistral Medium 3.5 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 | GPT-6 Sol | Bars | Mistral Medium 3.5 | Ties |
|---|---|---|---|---|
| Coding | 8 | 2 | ||
| Intelligence | 2 | 0 | ||
| Agentic work | 4 | 0 | ||
| Reasoning | 4 | 2 | ||
| Math | 1 | 2 | ||
| Knowledge | 1 | 4 | ||
| Web design | 8 | 0 | ||
| General | 12 | 13 | ||
| All shared boards | 40 | 23 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index82
| Benchmark | GPT-6 Sol | Mistral Medium 3.5 | Leader |
|---|---|---|---|
| LiveBench coding | 93.1% | Not measured | Only GPT-6 Sol measured |
| LMArena WebDev | 1683 | 1264 | GPT-6 Sol |
| AA Coding Index | Not measured | 46.9 | Only Mistral Medium 3.5 measured |
| SWE-bench Verified (Vals AI) | Not measured | 66.4% | Only Mistral Medium 3.5 measured |
| Terminal-Bench 4 (Vals AI) | 44.4% | Not measured | Only GPT-6 Sol measured |
| Vibe Code Bench (Vals AI) | 87.8% | 2.9% | GPT-6 Sol |
| Code migration (Vals AI) | 57.2% | 5.1% | GPT-6 Sol |
| ProgramBench (Vals AI) | 2.0% | Not measured | Only GPT-6 Sol measured |
| IOI (Vals AI) | 82.6% | Not measured | Only GPT-6 Sol measured |
| Terminal-Bench 2.1 (Vals AI) | 83.2% | 39.0% | GPT-6 Sol |
| CyberBench (Vals AI) | 78.0% | Not measured | Only GPT-6 Sol measured |
| SciCode | 57.6% | 40.2% | GPT-6 Sol |
| Terminal-Bench Hard (Artificial Analysis run) | Not measured | 33.3% | Only Mistral Medium 3.5 measured |
| FrontierCode | 49.3% | Not measured | Only GPT-6 Sol measured |
| ALE-Bench | 2462.0 | 764.0 | GPT-6 Sol |
| LMArena Text: coding | 1448 | 1460 | Mistral Medium 3.5 |
| LMArena Text: software and IT | 1433 | 1458 | Mistral Medium 3.5 |
| LMArena WebDev: React | 1685 | 1254 | GPT-6 Sol |
| LMArena WebDev: HTML | 1685 | 1308 | GPT-6 Sol |
| LMArena WebDev: from an image | 1660 | Not measured | Only GPT-6 Sol measured |
| Neither model has a result on the other 19 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | GPT-6 Sol | Mistral Medium 3.5 | Leader |
|---|---|---|---|
| AA Intelligence Index | 47.6 | 14.2 | GPT-6 Sol |
| Epoch Capabilities Index | 163.7 | 141.4 | GPT-6 Sol |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | GPT-6 Sol | Mistral Medium 3.5 | Leader |
|---|---|---|---|
| AA Agentic Index | Not measured | 7.0 | Only Mistral Medium 3.5 measured |
| Design Arena: agents building web apps | 1231 | Not measured | Only GPT-6 Sol measured |
| Design Arena: agents building full-stack apps | 1238 | Not measured | Only GPT-6 Sol measured |
| Design Arena: agents building mobile apps | 1214 | Not measured | Only GPT-6 Sol measured |
| LiveBench research | 69.3% | Not measured | Only GPT-6 Sol measured |
| LiveBench browser | 92.0% | Not measured | Only GPT-6 Sol measured |
| LiveBench long agentic | 66.9% | Not measured | Only GPT-6 Sol measured |
| SREBench (Vals AI) | 30.5% | Not measured | Only GPT-6 Sol measured |
| Finance Agent (Vals AI) | 49.0% | 32.1% | GPT-6 Sol |
| Tax Agent Bench (Vals AI) | 15.0% | 4.5% | GPT-6 Sol |
| Legal Research Bench (Vals AI) | 28.9% | 9.1% | GPT-6 Sol |
| Excel Modeling Benchmark (Vals AI) | 71.5% | 11.2% | GPT-6 Sol |
| BioMysteryBench (Vals AI) | 74.8% | Not measured | Only GPT-6 Sol measured |
| Terminal-Bench-Science (Vals AI) | 30.0% | Not measured | Only GPT-6 Sol measured |
| Vals Science Index | 45.0% | Not measured | Only GPT-6 Sol measured |
| τ²-Bench Telecom | Not measured | 94.2% | Only Mistral Medium 3.5 measured |
| APEX-Agents | 54.3% | Not measured | Only GPT-6 Sol measured |
| SpireClimb | 7.5% | Not measured | Only GPT-6 Sol measured |
| Vending-Bench 2 | $14,428 | Not measured | Only GPT-6 Sol measured |
| Neither model has a result on the other 22 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index42
| Benchmark | GPT-6 Sol | Mistral Medium 3.5 | Leader |
|---|---|---|---|
| GPQA Diamond | Not measured | 34.9% | Only Mistral Medium 3.5 measured |
| LiveBench reasoning | 88.7% | Not measured | Only GPT-6 Sol measured |
| MysteryMechanism (Vals AI) | 30.2% | Not measured | Only GPT-6 Sol measured |
| GPQA Diamond (Artificial Analysis run) | Not measured | 74.8% | Only Mistral Medium 3.5 measured |
| Humanity's Last Exam (Artificial Analysis run) | 47.9% | 13.8% | GPT-6 Sol |
| GPQA Diamond (Epoch AI run) | 94.3% | Not measured | Only GPT-6 Sol measured |
| ARC-AGI | 95.5% | Not measured | Only GPT-6 Sol measured |
| ARC-AGI-2 | 89.6% | Not measured | Only GPT-6 Sol measured |
| Chess puzzles | 56.0% | Not measured | Only GPT-6 Sol measured |
| Mystery game puzzles | 56.0% | Not measured | Only GPT-6 Sol measured |
| EBR-bench | 53.3% | Not measured | Only GPT-6 Sol measured |
| LMArena Text: hard prompts | 1422 | 1436 | Mistral Medium 3.5 |
| LMArena Text: expert | 1437 | 1432 | GPT-6 Sol |
| LMArena Text: hard prompts in English | 1420 | 1445 | Mistral Medium 3.5 |
| LMArena Vision: diagrams | 1270 | 1254 | GPT-6 Sol |
| LMArena Vision: homework | 1286 | 1230 | GPT-6 Sol |
| Kagi LLM Benchmark | Not measured | 41.4% | Only Mistral Medium 3.5 measured |
| Neither model has a result on the other 5 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index12
| Benchmark | GPT-6 Sol | Mistral Medium 3.5 | Leader |
|---|---|---|---|
| OTIS Mock AIME | 100.0% | Not measured | Only GPT-6 Sol measured |
| FrontierMath, tiers 1 to 3 | 89.8% | Not measured | Only GPT-6 Sol measured |
| FrontierMath, tier 4 | 90.0% | Not measured | Only GPT-6 Sol measured |
| ProofBench | 83.0% | 9.0% | GPT-6 Sol |
| LMArena Text: math | 1407 | 1431 | Mistral Medium 3.5 |
| LMArena Text: mathematical work | 1424 | 1440 | Mistral Medium 3.5 |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index14
| Benchmark | GPT-6 Sol | Mistral Medium 3.5 | Leader |
|---|---|---|---|
| MMLU Pro | Not measured | 75.3% | Only Mistral Medium 3.5 measured |
| CaseLaw (Vals AI) | Not measured | 44.2% | Only Mistral Medium 3.5 measured |
| CorpFin (Vals AI) | Not measured | 58.8% | Only Mistral Medium 3.5 measured |
| TaxEval (Vals AI) | Not measured | 68.0% | Only Mistral Medium 3.5 measured |
| MortgageTax (Vals AI) | Not measured | 28.9% | Only Mistral Medium 3.5 measured |
| MedCode (Vals AI) | 47.1% | 33.8% | GPT-6 Sol |
| SimpleQA Verified | 60.7% | Not measured | Only GPT-6 Sol measured |
| LMArena Text: science | 1389 | 1428 | Mistral Medium 3.5 |
| LMArena Text: medicine and healthcare | 1366 | 1409 | Mistral Medium 3.5 |
| LMArena Text: legal and government | 1396 | 1437 | Mistral Medium 3.5 |
| LMArena Text: business and finance | 1380 | 1426 | Mistral Medium 3.5 |
| FACTS Benchmark Suite | 72.5% | Not measured | Only GPT-6 Sol measured |
| Neither model has a result on the other 6 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index80
| Benchmark | GPT-6 Sol | Mistral Medium 3.5 | Leader |
|---|---|---|---|
| Design Arena: websites | 1292 | 1142 | GPT-6 Sol |
| Design Arena: UI components | 1292 | 1079 | GPT-6 Sol |
| Design Arena: game dev | 1314 | 1079 | GPT-6 Sol |
| Design Arena: data viz | 1269 | 1120 | GPT-6 Sol |
| Design Arena: 3D | 1318 | 1061 | GPT-6 Sol |
| Design Arena: all code categories | 1301 | 1121 | GPT-6 Sol |
| Design Arena: SVG | 1316 | 950 | GPT-6 Sol |
| Design Arena: ASCII art | 1225 | 1063 | GPT-6 Sol |
| LiveBench design | 82.2% | Not measured | Only GPT-6 Sol measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index1213
| Benchmark | GPT-6 Sol | Mistral Medium 3.5 | Leader |
|---|---|---|---|
| LiveBench data analysis | 81.2% | Not measured | Only GPT-6 Sol measured |
| Public Benefits Bench (Vals AI) | 56.6% | Not measured | Only GPT-6 Sol measured |
| SAGE (Vals AI) | 44.8% | 37.6% | GPT-6 Sol |
| MedScribe (Vals AI) | 82.0% | 67.7% | GPT-6 Sol |
| Vals Multimodal Index | Not measured | 34.8% | Only Mistral Medium 3.5 measured |
| IFBench | Not measured | 68.8% | Only Mistral Medium 3.5 measured |
| Long context reasoning (AA-LCR) | 83.7% | 69.3% | GPT-6 Sol |
| DTBench | 97.3% | 75.5% | GPT-6 Sol |
| LMCA | 59.1% | 26.1% | GPT-6 Sol |
| Surface Evolver Bench | Not measured | 26.9% | Only Mistral Medium 3.5 measured |
| Furniture assembly | 58.3% | Not measured | Only GPT-6 Sol measured |
| LMArena Text | 1398 | 1421 | Mistral Medium 3.5 |
| LMArena Text: instruction following | 1413 | 1415 | Mistral Medium 3.5 |
| LMArena Text: creative writing | 1378 | 1374 | GPT-6 Sol |
| LMArena Vision | 1240 | 1222 | GPT-6 Sol |
| LMArena Text: English | 1396 | 1433 | Mistral Medium 3.5 |
| LMArena Text: non-English | 1388 | 1404 | Mistral Medium 3.5 |
| LMArena Text: Chinese | 1412 | 1444 | Mistral Medium 3.5 |
| LMArena Text: German | 1379 | 1453 | Mistral Medium 3.5 |
| LMArena Text: Japanese | 1377 | Not measured | Only GPT-6 Sol measured |
| LMArena Text: Korean | 1336 | 1384 | Mistral Medium 3.5 |
| LMArena Text: French | 1399 | 1448 | Mistral Medium 3.5 |
| LMArena Text: Spanish | 1387 | 1411 | Mistral Medium 3.5 |
| LMArena Text: Russian | 1402 | 1395 | GPT-6 Sol |
| LMArena Text: Polish | 1372 | 1430 | Mistral Medium 3.5 |
| LMArena Text: multi-turn | 1414 | 1423 | Mistral Medium 3.5 |
| LMArena Text: longer queries | 1416 | 1415 | GPT-6 Sol |
| LMArena Text: writing and language | 1389 | 1384 | GPT-6 Sol |
| LMArena Text: entertainment and media | 1373 | 1382 | Mistral Medium 3.5 |
| LMArena Vision: English | 1229 | 1240 | Mistral Medium 3.5 |
| LMArena Vision: Chinese | Not measured | 1244 | Only Mistral Medium 3.5 measured |
| LMArena Vision: reading text | 1258 | 1233 | GPT-6 Sol |
| LMArena Vision: humor | Not measured | 1216 | Only Mistral Medium 3.5 measured |
| LMArena Vision: creative writing | 1219 | 1198 | GPT-6 Sol |
| Neither model has a result on the other 12 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | GPT-6 Sol | Mistral Medium 3.5 | 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
Mistral Medium 3.5 costs less
Repository review
50K input + 3K output tokens
Mistral Medium 3.5 costs less
Agent loop
200K input + 10K output tokens
Mistral Medium 3.5 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-6 Sol | Mistral Medium 3.5 |
|---|---|---|
| Maker | OpenAI | Mistral AI |
| Weights | No public weights listed | No public weights listed |
| Released | September 22, 2026 | April 30, 2026 |
| Context window | 1.05M | 262K |
| Input $/Mtok | $2.00 | $1.50 |
| Output $/Mtok | $10.00 | $7.50 |
| Coding index | 76.0 | 25.5 |
| Independent measurements behind it | 5 | 3 |
| Cost per solved task | Not computable | $6.02 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is GPT-6 Sol better than Mistral Medium 3.5 for coding?
Pick GPT-6 Sol for coding: it scores 76.0 on the Vibe Coding Index against 25.5 for Mistral Medium 3.5. Pick Mistral Medium 3.5 for output tokens 1.3x cheaper ($7.50 vs $10.00 per million) and work measured by LMArena Text: coding or LMArena Text: software and IT, where it leads.
Which is cheaper, GPT-6 Sol or Mistral Medium 3.5?
GPT-6 Sol costs $2.00 per million input tokens and $10.00 per million output tokens; Mistral Medium 3.5 costs $1.50 and $7.50. Cost per solved task is known for Mistral Medium 3.5 only.
Which has the bigger context window, GPT-6 Sol or Mistral Medium 3.5?
GPT-6 Sol, with 1.05M tokens against 262K.
How many benchmarks is the GPT-6 Sol vs Mistral Medium 3.5 comparison based on?
63 benchmarks have a result for both models as of October 21, 2026. GPT-6 Sol's coding index rests on 5 independent benchmarks and Mistral Medium 3.5's on 3. Where only one model has a result, the page says so instead of naming a winner.