Mistral Medium 3.1 vs Reka Flash 3
Mistral Medium 3.1 leads Reka Flash 3 on the Artificial Analysis Intelligence Index, 9.2 to 6.4, and Reka Flash 3 costs 10.0x less per output token ($0.20 vs $2.00 per million). Updated October 22, 2026; 11 benchmarks have a result for both.
Mistral Medium 3.1 or Reka Flash 3: which to pick
Neither model has a coding score yet, so the two cannot be ranked on coding.
Pick Mistral Medium 3.1 for a larger context window (131K against 66K tokens) and work measured by LiveCodeBench (Artificial Analysis run), where it leads.
- Shared results
- 11
- Mistral Medium 3.1 only
- 63
- Reka Flash 3 only
- 1
- Like-for-like categories
- 7 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
No call
Neither has a coding score yet.
One side not measured
Intelligence
AA Intelligence Index
Mistral Medium 3.1
Mistral Medium 3.1 leads, 9.2 against 6.4.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only Mistral Medium 3.1 has a AA Agentic Index result, 1.9.
Directional only
Math
AIME
No call
Only Mistral Medium 3.1 has a AIME result, 42.3%.
Directional only
Knowledge
MMLU Pro
No call
Only Mistral Medium 3.1 has a MMLU Pro result, 75.3%.
Directional only
Web design
Design Arena: websites
No call
Only Mistral Medium 3.1 has a Design Arena: websites result, 1132.
Directional only
Long documents
Listed context window
Mistral Medium 3.1
Mistral Medium 3.1 takes 131K tokens against 66K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Reka Flash 3
Mistral Medium 3.1 $0.0014, Reka Flash 3 $0.0002 per turn.
List prices
At a glance
- Coding index
- Mistral Medium 3.1 not benchmarked, Reka Flash 3 not benchmarked.
- Widest category
- Agentic work, 40.6 points apart on average over 1 shared benchmark.
- Widest single gap
- Long context reasoning (AA-LCR): Mistral Medium 3.1 42.7% against Reka Flash 3 0.0%, 42.7 points apart on a 0 to 100 scale.
- Output price
- Mistral Medium 3.1 $2.00 against Reka Flash 3 $0.20 per million output tokens, 10.0x apart.
- Context window
- Mistral Medium 3.1 takes 131K tokens, Reka Flash 3 66K.
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 | Mistral Medium 3.1 | Bars | Reka Flash 3 | Ties |
|---|---|---|---|---|
| Coding | 1 | 1 | ||
| Intelligence | 1 | 0 | ||
| Agentic work | 1 | 0 | ||
| Reasoning | 2 | 0 | ||
| Math | 2 | 0 | ||
| Knowledge | 1 | 0 | ||
| General | 2 | 0 | ||
| All shared boards | 10 | 1 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index11
| Benchmark | Mistral Medium 3.1 | Reka Flash 3 | Leader |
|---|---|---|---|
| AA Coding Index | 20.5 | Not measured | Only Mistral Medium 3.1 measured |
| LiveCodeBench (Vals AI) | 44.8% | Not measured | Only Mistral Medium 3.1 measured |
| LiveCodeBench (Artificial Analysis run) | 40.6% | 43.5% | Reka Flash 3 |
| SciCode | 32.4% | Not measured | Only Mistral Medium 3.1 measured |
| Terminal-Bench Hard (Artificial Analysis run) | 10.6% | 0.0% | Mistral Medium 3.1 |
| ALE-Bench | 210.2 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: coding | 1433 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: software and IT | 1436 | Not measured | Only Mistral Medium 3.1 measured |
| Neither model has a result on the other 35 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Mistral Medium 3.1 | Reka Flash 3 | Leader |
|---|---|---|---|
| AA Intelligence Index | 9.2 | 6.4 | Mistral Medium 3.1 |
| Neither model has a result on the other 1 board here | |||
Agentic workLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Mistral Medium 3.1 | Reka Flash 3 | Leader |
|---|---|---|---|
| AA Agentic Index | 1.9 | Not measured | Only Mistral Medium 3.1 measured |
| τ²-Bench Telecom | 40.6% | 0.0% | Mistral Medium 3.1 |
| BALROG | Not measured | 29.2% | Only Reka Flash 3 measured |
| Neither model has a result on the other 39 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Mistral Medium 3.1 | Reka Flash 3 | Leader |
|---|---|---|---|
| MMMU Pro (Vals AI) | 63.0% | Not measured | Only Mistral Medium 3.1 measured |
| GPQA Diamond (Artificial Analysis run) | 58.8% | 52.9% | Mistral Medium 3.1 |
| Humanity's Last Exam (Artificial Analysis run) | 4.7% | 4.4% | Mistral Medium 3.1 |
| LMArena Text: hard prompts | 1426 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: expert | 1408 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: hard prompts in English | 1435 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Vision: diagrams | 1175 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Vision: homework | 1165 | Not measured | Only Mistral Medium 3.1 measured |
| Neither model has a result on the other 15 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Mistral Medium 3.1 | Reka Flash 3 | Leader |
|---|---|---|---|
| AIME | 42.3% | Not measured | Only Mistral Medium 3.1 measured |
| MATH 500 (Vals AI) | 87.0% | Not measured | Only Mistral Medium 3.1 measured |
| MGSM (Vals AI) | 90.9% | Not measured | Only Mistral Medium 3.1 measured |
| AA Math Index | 38.3 | 33.7 | Mistral Medium 3.1 |
| AIME 2025 (Artificial Analysis run) | 38.3% | 33.7% | Mistral Medium 3.1 |
| LMArena Text: math | 1408 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: mathematical work | 1412 | Not measured | Only Mistral Medium 3.1 measured |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Mistral Medium 3.1 | Reka Flash 3 | Leader |
|---|---|---|---|
| MMLU Pro | 75.3% | Not measured | Only Mistral Medium 3.1 measured |
| LegalBench (Vals AI) | 62.0% | Not measured | Only Mistral Medium 3.1 measured |
| CorpFin (Vals AI) | 50.7% | Not measured | Only Mistral Medium 3.1 measured |
| TaxEval (Vals AI) | 70.3% | Not measured | Only Mistral Medium 3.1 measured |
| MortgageTax (Vals AI) | 36.5% | Not measured | Only Mistral Medium 3.1 measured |
| MedQA (Vals AI) | 78.2% | Not measured | Only Mistral Medium 3.1 measured |
| MMLU Pro (Artificial Analysis run) | 68.3% | 66.9% | Mistral Medium 3.1 |
| LMArena Text: science | 1444 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: medicine and healthcare | 1449 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: legal and government | 1439 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: business and finance | 1418 | Not measured | Only Mistral Medium 3.1 measured |
| Neither model has a result on the other 9 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index8 boards, none shared
| Benchmark | Mistral Medium 3.1 | Reka Flash 3 | Leader |
|---|---|---|---|
| Design Arena: websites | 1132 | Not measured | Only Mistral Medium 3.1 measured |
| Design Arena: UI components | 1097 | Not measured | Only Mistral Medium 3.1 measured |
| Design Arena: game dev | 1073 | Not measured | Only Mistral Medium 3.1 measured |
| Design Arena: data viz | 1144 | Not measured | Only Mistral Medium 3.1 measured |
| Design Arena: 3D | 1081 | Not measured | Only Mistral Medium 3.1 measured |
| Design Arena: all code categories | 1120 | Not measured | Only Mistral Medium 3.1 measured |
| Design Arena: SVG | 992 | Not measured | Only Mistral Medium 3.1 measured |
| Design Arena: ASCII art | 997 | Not measured | Only Mistral Medium 3.1 measured |
| Neither model has a result on the other 1 board here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Mistral Medium 3.1 | Reka Flash 3 | Leader |
|---|---|---|---|
| IFBench | 39.8% | 30.4% | Mistral Medium 3.1 |
| Long context reasoning (AA-LCR) | 42.7% | 0.0% | Mistral Medium 3.1 |
| DTBench | 67.5% | Not measured | Only Mistral Medium 3.1 measured |
| LMCA | 19.1% | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text | 1424 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: instruction following | 1398 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: creative writing | 1391 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Vision | 1172 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: English | 1438 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: non-English | 1408 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: Chinese | 1447 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: German | 1432 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: Japanese | 1379 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: Korean | 1380 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: French | 1460 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: Spanish | 1433 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: Russian | 1411 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: Polish | 1430 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: multi-turn | 1418 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: longer queries | 1406 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: writing and language | 1395 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Text: entertainment and media | 1390 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Vision: English | 1179 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Vision: Chinese | 1190 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Vision: reading text | 1175 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Vision: humor | 1168 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Vision: captioning | 1145 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Vision: recognizing things | 1147 | Not measured | Only Mistral Medium 3.1 measured |
| LMArena Vision: creative writing | 1200 | Not measured | Only Mistral Medium 3.1 measured |
| Neither model has a result on the other 19 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Mistral Medium 3.1 | Reka Flash 3 | 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
Reka Flash 3 costs less
Repository review
50K input + 3K output tokens
Reka Flash 3 costs less
Agent loop
200K input + 10K output tokens
Reka Flash 3 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 | Mistral Medium 3.1 | Reka Flash 3 |
|---|---|---|
| Maker | Mistral AI | Reka |
| Weights | No public weights listed | Open weights |
| Released | August 13, 2025 | March 12, 2025 |
| Context window | 131K | 66K |
| Input $/Mtok | $0.40 | $0.10 |
| Output $/Mtok | $2.00 | $0.20 |
| Coding index | Not benchmarked | Not benchmarked |
| Independent measurements behind it | 0 | 0 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Mistral Medium 3.1 better than Reka Flash 3 for coding?
Neither model has a coding score yet, so the two cannot be ranked on coding. Pick Mistral Medium 3.1 for a larger context window (131K against 66K tokens) and work measured by LiveCodeBench (Artificial Analysis run), where it leads.
Which is cheaper, Mistral Medium 3.1 or Reka Flash 3?
Mistral Medium 3.1 costs $0.40 per million input tokens and $2.00 per million output tokens; Reka Flash 3 costs $0.10 and $0.20. Cost per solved task is known for neither of them.
Which has the bigger context window, Mistral Medium 3.1 or Reka Flash 3?
Mistral Medium 3.1, with 131K tokens against 66K.
How many benchmarks is the Mistral Medium 3.1 vs Reka Flash 3 comparison based on?
11 benchmarks have a result for both models as of October 22, 2026. Mistral Medium 3.1's coding index rests on 0 independent benchmarks and Reka Flash 3's on 0. Where only one model has a result, the page says so instead of naming a winner.