DeepSeek V4 Flash 0423 vs Devstral 2 2512
Updated October 21, 2026. 3 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
Decision reading
DeepSeek V4 Flash 0423 and Devstral 2 2512 are level for coding, 54.6 against 53.8 on the Vibe Coding Index, so price and context decide.
Devstral 2 2512 is neither cheaper nor larger in context, and leads no benchmark both models were measured on. Pick DeepSeek V4 Flash 0423 when output tokens cost 11.0x less, or when the context window is larger, 1.05M against 262K tokens.
- Shared results
- 3
- DeepSeek V4 Flash 0423 only
- 45
- Devstral 2 2512 only
- 3
- Like-for-like categories
- 3 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
No call
Level: 54.6 against 53.8, inside 2 points.
One benchmark behind each score
Intelligence
AA Intelligence Index
DeepSeek V4 Flash 0423
DeepSeek V4 Flash 0423 leads, 24.4 against 8.6.
Same board, both measured
Agentic work
AA Agentic Index
DeepSeek V4 Flash 0423
DeepSeek V4 Flash 0423 leads, 26.3 against 2.3.
Same board, both measured
Web design
Design Arena: websites
No call
Only DeepSeek V4 Flash 0423 has a Design Arena: websites result, 1208.
Directional only
Long documents
Listed context window
DeepSeek V4 Flash 0423
DeepSeek V4 Flash 0423 takes 1.05M tokens against 262K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
DeepSeek V4 Flash 0423
DeepSeek V4 Flash 0423 $0.0002, Devstral 2 2512 $0.0014 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Devstral 2 2512 has the number, $1.19.
Directional only
At a glance
- Coding index
- DeepSeek V4 Flash 0423 54.6 from 1 benchmark, Devstral 2 2512 53.8 from 1 benchmark.
- Widest category
- Agentic work, 24.0 points apart on average over 1 shared benchmark.
- Widest single gap
- AA Agentic Index: DeepSeek V4 Flash 0423 26.3 against Devstral 2 2512 2.3, 24.0 points apart on a 0 to 100 scale.
- Output price
- DeepSeek V4 Flash 0423 $0.182 against Devstral 2 2512 $2.00 per million output tokens, 11.0x apart.
- Context window
- DeepSeek V4 Flash 0423 takes 1.05M tokens, Devstral 2 2512 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 | DeepSeek V4 Flash 0423 | Bars | Devstral 2 2512 | Ties |
|---|---|---|---|---|
| Coding | 1 | 0 | ||
| Intelligence | 1 | 0 | ||
| Agentic work | 1 | 0 | ||
| All shared boards | 3 | 0 |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index10
| Benchmark | DeepSeek V4 Flash 0423 | Devstral 2 2512 | Leader |
|---|---|---|---|
| SWE-bench Verified | Not measured | 53.8% | Only Devstral 2 2512 measured |
| LMArena WebDev | 1582 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| AA Coding Index | 52.0 | 31.3 | DeepSeek V4 Flash 0423 |
| LiveCodeBench (Vals AI) | Not measured | 51.8% | Only Devstral 2 2512 measured |
| SWE-bench Verified (Vals AI) | Not measured | 62.8% | Only Devstral 2 2512 measured |
| WeirdML | 45.6% | Not measured | Only DeepSeek V4 Flash 0423 measured |
| ALE-Bench | 678.2 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: coding | 1457 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: software and IT | 1453 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena WebDev: React | 1585 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena WebDev: HTML | 1558 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| Neither model has a result on the other 27 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | DeepSeek V4 Flash 0423 | Devstral 2 2512 | Leader |
|---|---|---|---|
| AA Intelligence Index | 24.4 | 8.6 | DeepSeek V4 Flash 0423 |
| Epoch Capabilities Index | 146.1 | Not measured | Only DeepSeek V4 Flash 0423 measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | DeepSeek V4 Flash 0423 | Devstral 2 2512 | Leader |
|---|---|---|---|
| AA Agentic Index | 26.3 | 2.3 | DeepSeek V4 Flash 0423 |
| Neither model has a result on the other 38 boards here | |||
ReasoningDirectional onlyPublic boards, shown as published, kept out of the index4 boards, none shared
| Benchmark | DeepSeek V4 Flash 0423 | Devstral 2 2512 | Leader |
|---|---|---|---|
| SimpleBench | 46.3% | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: hard prompts | 1444 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: expert | 1441 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: hard prompts in English | 1449 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| Neither model has a result on the other 17 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index2 boards, none shared
| Benchmark | DeepSeek V4 Flash 0423 | Devstral 2 2512 | Leader |
|---|---|---|---|
| LMArena Text: math | 1426 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: mathematical work | 1432 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| Neither model has a result on the other 11 boards here | |||
KnowledgeDirectional onlyPublic boards, shown as published, kept out of the index4 boards, none shared
| Benchmark | DeepSeek V4 Flash 0423 | Devstral 2 2512 | Leader |
|---|---|---|---|
| LMArena Text: science | 1446 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: medicine and healthcare | 1448 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: legal and government | 1439 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: business and finance | 1425 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| Neither model has a result on the other 13 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index8 boards, none shared
| Benchmark | DeepSeek V4 Flash 0423 | Devstral 2 2512 | Leader |
|---|---|---|---|
| Design Arena: websites | 1208 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| Design Arena: UI components | 1164 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| Design Arena: game dev | 1197 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| Design Arena: data viz | 1127 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| Design Arena: 3D | 1189 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| Design Arena: all code categories | 1205 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| Design Arena: SVG | 1155 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| Design Arena: ASCII art | 1109 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| Neither model has a result on the other 1 board here | |||
GeneralDirectional onlyPublic boards, shown as published, kept out of the index19 boards, none shared
| Benchmark | DeepSeek V4 Flash 0423 | Devstral 2 2512 | Leader |
|---|---|---|---|
| DTBench | 86.4% | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMCA | 35.9% | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text | 1432 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: instruction following | 1421 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: creative writing | 1403 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: English | 1441 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: non-English | 1419 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: Chinese | 1463 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: German | 1419 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: Japanese | 1389 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: Korean | 1383 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: French | 1439 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: Spanish | 1436 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: Russian | 1427 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: Polish | 1436 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: multi-turn | 1449 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: longer queries | 1434 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: writing and language | 1410 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| LMArena Text: entertainment and media | 1400 | Not measured | Only DeepSeek V4 Flash 0423 measured |
| Neither model has a result on the other 27 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | DeepSeek V4 Flash 0423 | Devstral 2 2512 | 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
DeepSeek V4 Flash 0423 costs less
Repository review
50K input + 3K output tokens
DeepSeek V4 Flash 0423 costs less
Agent loop
200K input + 10K output tokens
DeepSeek V4 Flash 0423 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 | DeepSeek V4 Flash 0423 | Mistral Devstral 2 2512 |
|---|---|---|
| Maker | DeepSeek | Mistral AI |
| Weights | Open weights | Open weights |
| Released | April 24, 2026 | December 9, 2025 |
| Context window | 1.05M | 262K |
| Input $/Mtok | $0.091 | $0.40 |
| Output $/Mtok | $0.182 | $2.00 |
| Coding index | 54.6 | 53.8 |
| Independent measurements behind it | 1 | 1 |
| Cost per solved task | Not computable | $1.19 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is DeepSeek V4 Flash 0423 better than Devstral 2 2512 for coding?
DeepSeek V4 Flash 0423 and Devstral 2 2512 are level for coding, 54.6 against 53.8 on the Vibe Coding Index, so price and context decide. Devstral 2 2512 is neither cheaper nor larger in context, and leads no benchmark both models were measured on. Pick DeepSeek V4 Flash 0423 when output tokens cost 11.0x less, or when the context window is larger, 1.05M against 262K tokens.
Which is cheaper, DeepSeek V4 Flash 0423 or Devstral 2 2512?
DeepSeek V4 Flash 0423 costs $0.091 per million input tokens and $0.182 per million output tokens; Devstral 2 2512 costs $0.40 and $2.00. Cost per solved task is known for Devstral 2 2512 only.
Which has the bigger context window, DeepSeek V4 Flash 0423 or Devstral 2 2512?
DeepSeek V4 Flash 0423, with 1.05M tokens against 262K.
How many benchmarks is the DeepSeek V4 Flash 0423 vs Devstral 2 2512 comparison based on?
3 benchmarks have a result for both models as of October 21, 2026. DeepSeek V4 Flash 0423's coding index rests on 1 independent benchmark and Devstral 2 2512's on 1. Where only one model has a result, the page says so instead of naming a winner.