Claude Fable 5 vs Mistral Medium 3.5
Updated October 21, 2026. 79 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
Decision reading
Pick Claude Fable 5 for coding: it scores 82.1 on the Vibe Coding Index against 9.2 for Mistral Medium 3.5.
Pick Mistral Medium 3.5 when output tokens cost 6.7x less, or when the benchmark that matters is IFBench, where it leads.
- Shared results
- 79
- Claude Fable 5 only
- 47
- Mistral Medium 3.5 only
- 1
- Like-for-like categories
- 8 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
Claude Fable 5
Claude Fable 5 scores 82.1 against 9.2.
2 and 1 benchmarks behind the scores
Intelligence
AA Intelligence Index
Claude Fable 5
Claude Fable 5 leads, 49.6 against 14.2.
Same board, both measured
Agentic work
AA Agentic Index
Claude Fable 5
Claude Fable 5 leads, 50.7 against 7.0.
Same board, both measured
Reasoning
GPQA Diamond
Claude Fable 5
Claude Fable 5 leads, 93.2% against 34.9%.
Same board, both measured
Knowledge
MMLU Pro
Claude Fable 5
Claude Fable 5 leads, 91.5% against 75.3%.
Same board, both measured
Web design
Design Arena: websites
Claude Fable 5
Claude Fable 5 leads, 1296 against 1142.
Same board, both measured
Long documents
Listed context window
Claude Fable 5
Claude Fable 5 takes 1M tokens against 262K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Mistral Medium 3.5
Claude Fable 5 $0.035, Mistral Medium 3.5 $0.0053 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
Claude Fable 5
Claude Fable 5 $2.16, Mistral Medium 3.5 $6.02.
Published attempt cost and pass rate
At a glance
- Coding index
- Claude Fable 5 82.1 from 2 benchmarks, Mistral Medium 3.5 9.2 from 1 benchmark.
- Widest category
- Coding, 39.0 points apart on average over 13 shared benchmarks.
- Widest single gap
- Vibe Code Bench (Vals AI): Claude Fable 5 90.3% against Mistral Medium 3.5 2.9%, 87.5 points apart on a 0 to 100 scale.
- Output price
- Claude Fable 5 $50.00 against Mistral Medium 3.5 $7.50 per million output tokens, 6.7x apart.
- Context window
- Claude Fable 5 takes 1M 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 | Claude Fable 5 | Bars | Mistral Medium 3.5 | Ties |
|---|---|---|---|---|
| Coding | 13 | 0 | ||
| Intelligence | 2 | 0 | ||
| Agentic work | 6 | 0 | ||
| Reasoning | 8 | 0 | ||
| Math | 3 | 0 | ||
| Knowledge | 9 | 0 | ||
| Web design | 8 | 0 | ||
| General | 29 | 1 | ||
| All shared boards | 78 | 1 |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index130
| Benchmark | Claude Fable 5 | Mistral Medium 3.5 | Leader |
|---|---|---|---|
| LiveBench coding | 98.3% | Not measured | Only Claude Fable 5 measured |
| LMArena WebDev | 1624 | 1264 | Claude Fable 5 |
| AA Coding Index | 76.5 | 46.9 | Claude Fable 5 |
| LiveCodeBench (Vals AI) | 89.8% | Not measured | Only Claude Fable 5 measured |
| SWE-bench Verified (Vals AI) | 95.0% | 66.4% | Claude Fable 5 |
| Terminal-Bench 4 (Vals AI) | 41.4% | Not measured | Only Claude Fable 5 measured |
| Vibe Code Bench (Vals AI) | 90.3% | 2.9% | Claude Fable 5 |
| Code migration (Vals AI) | 55.1% | 5.1% | Claude Fable 5 |
| ProgramBench (Vals AI) | 2.0% | Not measured | Only Claude Fable 5 measured |
| Terminal-Bench 2.1 (Vals AI) | 80.5% | 39.0% | Claude Fable 5 |
| SciCode | 61.0% | 40.2% | Claude Fable 5 |
| Terminal-Bench Hard (Artificial Analysis run) | 62.9% | 33.3% | Claude Fable 5 |
| FrontierCode | 53.5% | Not measured | Only Claude Fable 5 measured |
| FrontierSWE | 47.0% | Not measured | Only Claude Fable 5 measured |
| GSO-Bench | 78.4% | Not measured | Only Claude Fable 5 measured |
| WeirdML | 91.9% | Not measured | Only Claude Fable 5 measured |
| MirrorCode | 63.9% | Not measured | Only Claude Fable 5 measured |
| ALE-Bench | 2041.3 | 764.0 | Claude Fable 5 |
| LMArena Text: coding | 1518 | 1460 | Claude Fable 5 |
| LMArena Text: software and IT | 1513 | 1458 | Claude Fable 5 |
| LMArena WebDev: React | 1631 | 1254 | Claude Fable 5 |
| LMArena WebDev: HTML | 1651 | 1308 | Claude Fable 5 |
| LMArena WebDev: from an image | 1623 | Not measured | Only Claude Fable 5 measured |
| Neither model has a result on the other 15 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Claude Fable 5 | Mistral Medium 3.5 | Leader |
|---|---|---|---|
| AA Intelligence Index | 49.6 | 14.2 | Claude Fable 5 |
| Epoch Capabilities Index | 163.4 | 141.4 | Claude Fable 5 |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | Claude Fable 5 | Mistral Medium 3.5 | Leader |
|---|---|---|---|
| AA Agentic Index | 50.7 | 7.0 | Claude Fable 5 |
| Design Arena: agents building web apps | 1261 | Not measured | Only Claude Fable 5 measured |
| Design Arena: agents building full-stack apps | 1280 | Not measured | Only Claude Fable 5 measured |
| Design Arena: agents building mobile apps | 1264 | Not measured | Only Claude Fable 5 measured |
| Design Arena: agents building Android apps | 1289 | Not measured | Only Claude Fable 5 measured |
| Design Arena: agents building Godot games | 1292 | Not measured | Only Claude Fable 5 measured |
| Design Arena: agents building games | 1285 | Not measured | Only Claude Fable 5 measured |
| Design Arena: HTML slides | 1277 | Not measured | Only Claude Fable 5 measured |
| Design Arena: PowerPoint slides | 1295 | Not measured | Only Claude Fable 5 measured |
| LiveBench research | 86.9% | Not measured | Only Claude Fable 5 measured |
| LiveBench browser | 92.0% | Not measured | Only Claude Fable 5 measured |
| LiveBench long agentic | 53.2% | Not measured | Only Claude Fable 5 measured |
| Finance Agent (Vals AI) | 56.3% | 32.1% | Claude Fable 5 |
| Tax Agent Bench (Vals AI) | 38.3% | 4.5% | Claude Fable 5 |
| Legal Research Bench (Vals AI) | 49.5% | 9.1% | Claude Fable 5 |
| Excel Modeling Benchmark (Vals AI) | 73.7% | 11.2% | Claude Fable 5 |
| Terminal-Bench-Science (Vals AI) | 15.7% | Not measured | Only Claude Fable 5 measured |
| τ²-Bench Telecom | 98.5% | 94.2% | Claude Fable 5 |
| APEX-Agents | 63.6% | Not measured | Only Claude Fable 5 measured |
| Remote Labor Index | 16.1% | Not measured | Only Claude Fable 5 measured |
| PostTrainBench | 41.8% | Not measured | Only Claude Fable 5 measured |
| Vending-Bench 2 | $5,680 | Not measured | Only Claude Fable 5 measured |
| LMArena Search | 1229 | Not measured | Only Claude Fable 5 measured |
| Neither model has a result on the other 16 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index80
| Benchmark | Claude Fable 5 | Mistral Medium 3.5 | Leader |
|---|---|---|---|
| GPQA Diamond | 93.2% | 34.9% | Claude Fable 5 |
| LiveBench reasoning | 89.7% | Not measured | Only Claude Fable 5 measured |
| MMMU Pro (Vals AI) | 89.3% | Not measured | Only Claude Fable 5 measured |
| GPQA Diamond (Artificial Analysis run) | 92.6% | 74.8% | Claude Fable 5 |
| Humanity's Last Exam (Artificial Analysis run) | 55.5% | 13.8% | Claude Fable 5 |
| GPQA Diamond (Epoch AI run) | 85.9% | Not measured | Only Claude Fable 5 measured |
| ARC-AGI | 98.5% | Not measured | Only Claude Fable 5 measured |
| ARC-AGI-2 | 89.2% | Not measured | Only Claude Fable 5 measured |
| SimpleBench | 81.9% | Not measured | Only Claude Fable 5 measured |
| Chess puzzles | 47.0% | Not measured | Only Claude Fable 5 measured |
| Mystery game puzzles | 52.0% | Not measured | Only Claude Fable 5 measured |
| EBR-bench | 39.5% | Not measured | Only Claude Fable 5 measured |
| LMArena Text: hard prompts | 1507 | 1436 | Claude Fable 5 |
| LMArena Text: expert | 1534 | 1432 | Claude Fable 5 |
| LMArena Text: hard prompts in English | 1509 | 1445 | Claude Fable 5 |
| LMArena Vision: diagrams | 1357 | 1254 | Claude Fable 5 |
| LMArena Vision: homework | 1361 | 1230 | Claude Fable 5 |
| Neither model has a result on the other 4 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index30
| Benchmark | Claude Fable 5 | Mistral Medium 3.5 | Leader |
|---|---|---|---|
| OTIS Mock AIME | 100.0% | Not measured | Only Claude Fable 5 measured |
| FrontierMath, tiers 1 to 3 | 87.0% | Not measured | Only Claude Fable 5 measured |
| FrontierMath, tier 4 | 90.2% | Not measured | Only Claude Fable 5 measured |
| ProofBench | 95.0% | 9.0% | Claude Fable 5 |
| LMArena Text: math | 1516 | 1431 | Claude Fable 5 |
| LMArena Text: mathematical work | 1515 | 1440 | Claude Fable 5 |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index90
| Benchmark | Claude Fable 5 | Mistral Medium 3.5 | Leader |
|---|---|---|---|
| MMLU Pro | 91.5% | 75.3% | Claude Fable 5 |
| LegalBench (Vals AI) | 88.6% | Not measured | Only Claude Fable 5 measured |
| CaseLaw (Vals AI) | Not measured | 44.2% | Only Mistral Medium 3.5 measured |
| CorpFin (Vals AI) | 71.8% | 58.8% | Claude Fable 5 |
| TaxEval (Vals AI) | 76.9% | 68.0% | Claude Fable 5 |
| MortgageTax (Vals AI) | 68.9% | 28.9% | Claude Fable 5 |
| MedCode (Vals AI) | 56.1% | 33.8% | Claude Fable 5 |
| SimpleQA Verified | 70.7% | Not measured | Only Claude Fable 5 measured |
| LMArena Text: science | 1506 | 1428 | Claude Fable 5 |
| LMArena Text: medicine and healthcare | 1480 | 1409 | Claude Fable 5 |
| LMArena Text: legal and government | 1498 | 1437 | Claude Fable 5 |
| LMArena Text: business and finance | 1480 | 1426 | Claude Fable 5 |
| Neither model has a result on the other 5 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index80
| Benchmark | Claude Fable 5 | Mistral Medium 3.5 | Leader |
|---|---|---|---|
| Design Arena: websites | 1296 | 1142 | Claude Fable 5 |
| Design Arena: UI components | 1318 | 1079 | Claude Fable 5 |
| Design Arena: game dev | 1336 | 1079 | Claude Fable 5 |
| Design Arena: data viz | 1304 | 1120 | Claude Fable 5 |
| Design Arena: 3D | 1319 | 1061 | Claude Fable 5 |
| Design Arena: all code categories | 1310 | 1122 | Claude Fable 5 |
| Design Arena: SVG | 1302 | 949 | Claude Fable 5 |
| Design Arena: ASCII art | 1328 | 1062 | Claude Fable 5 |
| LiveBench design | 84.7% | Not measured | Only Claude Fable 5 measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index291
| Benchmark | Claude Fable 5 | Mistral Medium 3.5 | Leader |
|---|---|---|---|
| LiveBench data analysis | 80.5% | Not measured | Only Claude Fable 5 measured |
| Public Benefits Bench (Vals AI) | 70.4% | Not measured | Only Claude Fable 5 measured |
| SAGE (Vals AI) | 51.9% | 37.6% | Claude Fable 5 |
| MedScribe (Vals AI) | 88.5% | 67.7% | Claude Fable 5 |
| Vals Multimodal Index | 74.2% | 34.8% | Claude Fable 5 |
| IFBench | 63.5% | 68.8% | Mistral Medium 3.5 |
| Long context reasoning (AA-LCR) | 82.3% | 69.3% | Claude Fable 5 |
| DTBench | 98.4% | 75.5% | Claude Fable 5 |
| LMCA | 61.2% | 26.1% | Claude Fable 5 |
| Surface Evolver Bench | 95.0% | 26.9% | Claude Fable 5 |
| Furniture assembly | 35.8% | Not measured | Only Claude Fable 5 measured |
| LMArena Text | 1491 | 1421 | Claude Fable 5 |
| LMArena Text: instruction following | 1502 | 1415 | Claude Fable 5 |
| LMArena Text: creative writing | 1494 | 1374 | Claude Fable 5 |
| LMArena Vision | 1325 | 1222 | Claude Fable 5 |
| LMArena Text: English | 1498 | 1433 | Claude Fable 5 |
| LMArena Text: non-English | 1482 | 1404 | Claude Fable 5 |
| LMArena Text: Chinese | 1543 | 1444 | Claude Fable 5 |
| LMArena Text: German | 1486 | 1453 | Claude Fable 5 |
| LMArena Text: Japanese | 1504 | Not measured | Only Claude Fable 5 measured |
| LMArena Text: Korean | 1487 | 1384 | Claude Fable 5 |
| LMArena Text: French | 1505 | 1448 | Claude Fable 5 |
| LMArena Text: Spanish | 1498 | 1411 | Claude Fable 5 |
| LMArena Text: Russian | 1503 | 1395 | Claude Fable 5 |
| LMArena Text: Polish | 1494 | 1430 | Claude Fable 5 |
| LMArena Text: multi-turn | 1504 | 1423 | Claude Fable 5 |
| LMArena Text: longer queries | 1510 | 1415 | Claude Fable 5 |
| LMArena Text: writing and language | 1501 | 1384 | Claude Fable 5 |
| LMArena Text: entertainment and media | 1482 | 1382 | Claude Fable 5 |
| LMArena Vision: English | 1323 | 1240 | Claude Fable 5 |
| LMArena Vision: Chinese | 1373 | 1244 | Claude Fable 5 |
| LMArena Vision: reading text | 1337 | 1233 | Claude Fable 5 |
| LMArena Vision: humor | 1341 | 1216 | Claude Fable 5 |
| LMArena Vision: creative writing | 1338 | 1198 | Claude Fable 5 |
| LMArena Document | 1496 | Not measured | Only Claude Fable 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 | Claude Fable 5 | 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 | Anthropic Claude Fable 5 | Mistral Medium 3.5 |
|---|---|---|
| Maker | Anthropic | Mistral AI |
| Weights | No public weights listed | No public weights listed |
| Released | June 9, 2026 | April 30, 2026 |
| Context window | 1M | 262K |
| Input $/Mtok | $10.00 | $1.50 |
| Output $/Mtok | $50.00 | $7.50 |
| Coding index | 82.1 | 9.2 |
| Independent measurements behind it | 2 | 1 |
| Cost per solved task | $2.16 | $6.02 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Fable 5 better than Mistral Medium 3.5 for coding?
Pick Claude Fable 5 for coding: it scores 82.1 on the Vibe Coding Index against 9.2 for Mistral Medium 3.5. Pick Mistral Medium 3.5 when output tokens cost 6.7x less, or when the benchmark that matters is IFBench, where it leads.
Which is cheaper, Claude Fable 5 or Mistral Medium 3.5?
Claude Fable 5 costs $10.00 per million input tokens and $50.00 per million output tokens; Mistral Medium 3.5 costs $1.50 and $7.50. Per solved SWE-bench Verified task, Claude Fable 5 costs $2.16 and Mistral Medium 3.5 $6.02.
Which has the bigger context window, Claude Fable 5 or Mistral Medium 3.5?
Claude Fable 5, with 1M tokens against 262K.
How many benchmarks is the Claude Fable 5 vs Mistral Medium 3.5 comparison based on?
79 benchmarks have a result for both models as of October 21, 2026. Claude Fable 5's coding index rests on 2 independent benchmarks and Mistral Medium 3.5's on 1. Where only one model has a result, the page says so instead of naming a winner.