Claude Opus 5.5 vs DeepSeek V4 Pro 0423
Claude Opus 5.5 leads DeepSeek V4 Pro 0423 on coding, 88.8 to 38.7 on the Vibe Coding Index, and DeepSeek V4 Pro 0423 costs 7.4x less per output token ($2.716 vs $20.00 per million). Updated October 21, 2026; 63 benchmarks have a result for both.
Claude Opus 5.5 or DeepSeek V4 Pro 0423: which to pick
Pick Claude Opus 5.5 for coding: it scores 88.8 on the Vibe Coding Index against 38.7 for DeepSeek V4 Pro 0423.
Pick DeepSeek V4 Pro 0423 for output tokens 7.4x cheaper ($2.716 vs $20.00 per million) and a larger context window (1.05M against 1M tokens).
- Shared results
- 63
- Claude Opus 5.5 only
- 46
- DeepSeek V4 Pro 0423 only
- 21
- 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
Claude Opus 5.5
Claude Opus 5.5 scores 88.8 against 38.7.
5 benchmarks behind each score
Intelligence
AA Intelligence Index
Claude Opus 5.5
Claude Opus 5.5 leads, 57.6 against 30.4.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only DeepSeek V4 Pro 0423 has a AA Agentic Index result, 26.3.
Directional only
Reasoning
GPQA Diamond
No call
Only DeepSeek V4 Pro 0423 has a GPQA Diamond result, 89.4%.
Directional only
Knowledge
MMLU Pro
No call
Only DeepSeek V4 Pro 0423 has a MMLU Pro result, 87.3%.
Directional only
Web design
Design Arena: websites
Claude Opus 5.5
Claude Opus 5.5 leads, 1336 against 1234.
Same board, both measured
General
Vals Index
No call
Only Claude Opus 5.5 has a Vals Index result, 70.2%.
Directional only
Long documents
Listed context window
DeepSeek V4 Pro 0423
DeepSeek V4 Pro 0423 takes 1.05M tokens against 1M.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
DeepSeek V4 Pro 0423
Claude Opus 5.5 $0.014, DeepSeek V4 Pro 0423 $0.0026 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only DeepSeek V4 Pro 0423 has the number, $0.57.
Directional only
At a glance
- Coding index
- Claude Opus 5.5 88.8 from 5 benchmarks, DeepSeek V4 Pro 0423 38.7 from 5 benchmarks.
- Widest category
- Math, 41.4 points apart on average over 6 shared benchmarks.
- Widest single gap
- FrontierMath, tier 4: Claude Opus 5.5 95.0% against DeepSeek V4 Pro 0423 2.4%, 92.6 points apart on a 0 to 100 scale.
- Output price
- Claude Opus 5.5 $20.00 against DeepSeek V4 Pro 0423 $2.716 per million output tokens, 7.4x apart.
- Context window
- Claude Opus 5.5 takes 1M tokens, DeepSeek V4 Pro 0423 1.05M.
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 Opus 5.5 | Bars | DeepSeek V4 Pro 0423 | Ties |
|---|---|---|---|---|
| Coding | 12 | 0 | ||
| Intelligence | 2 | 0 | ||
| Agentic work | 6 | 0 | ||
| Reasoning | 5 | 1 | ||
| Math | 6 | 0 | ||
| Knowledge | 6 | 0 | ||
| Web design | 7 | 0 | ||
| General | 18 | 0 | ||
| All shared boards | 62 | 1 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index120
| Benchmark | Claude Opus 5.5 | DeepSeek V4 Pro 0423 | Leader |
|---|---|---|---|
| LiveBench coding | 96.3% | Not measured | Only Claude Opus 5.5 measured |
| LMArena WebDev | 1807 | 1447 | Claude Opus 5.5 |
| AA Coding Index | Not measured | 59.4 | Only DeepSeek V4 Pro 0423 measured |
| LiveCodeBench (Vals AI) | Not measured | 87.5% | Only DeepSeek V4 Pro 0423 measured |
| SWE-bench Verified (Vals AI) | Not measured | 77.4% | Only DeepSeek V4 Pro 0423 measured |
| Terminal-Bench 4 (Vals AI) | 65.2% | 11.1% | Claude Opus 5.5 |
| Vibe Code Bench (Vals AI) | 90.3% | 49.9% | Claude Opus 5.5 |
| Code migration (Vals AI) | 66.7% | 26.2% | Claude Opus 5.5 |
| ProgramBench (Vals AI) | 18.5% | 0.0% | Claude Opus 5.5 |
| IOI (Vals AI) | 95.1% | Not measured | Only Claude Opus 5.5 measured |
| Terminal-Bench 2.1 (Vals AI) | 87.6% | 50.2% | Claude Opus 5.5 |
| SWE-bench Multimodal (Vals AI) | 70.2% | Not measured | Only Claude Opus 5.5 measured |
| Vibe Code Bench 1-100 (Vals AI) | 30.4% | Not measured | Only Claude Opus 5.5 measured |
| SkillsBench (Vals AI) | Not measured | 51.3% | Only DeepSeek V4 Pro 0423 measured |
| CyberBench (Vals AI) | 74.6% | Not measured | Only Claude Opus 5.5 measured |
| SciCode | 66.9% | Not measured | Only Claude Opus 5.5 measured |
| FrontierCode | 54.6% | 17.6% | Claude Opus 5.5 |
| FrontierSWE | 62.3% | Not measured | Only Claude Opus 5.5 measured |
| WeirdML | Not measured | 48.9% | Only DeepSeek V4 Pro 0423 measured |
| MirrorCode | 77.4% | Not measured | Only Claude Opus 5.5 measured |
| ALE-Bench | 2147.4 | 1006.1 | Claude Opus 5.5 |
| LMArena Text: coding | 1545 | 1470 | Claude Opus 5.5 |
| LMArena Text: software and IT | 1538 | 1469 | Claude Opus 5.5 |
| LMArena WebDev: React | 1855 | 1441 | Claude Opus 5.5 |
| LMArena WebDev: HTML | 1753 | 1435 | Claude Opus 5.5 |
| LMArena WebDev: from an image | 1753 | Not measured | Only Claude Opus 5.5 measured |
| SciCode | 18.5% | Not measured | Only Claude Opus 5.5 measured |
| Neither model has a result on the other 12 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Claude Opus 5.5 | DeepSeek V4 Pro 0423 | Leader |
|---|---|---|---|
| AA Intelligence Index | 57.6 | 30.4 | Claude Opus 5.5 |
| Epoch Capabilities Index | 168.8 | 149.1 | Claude Opus 5.5 |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | Claude Opus 5.5 | DeepSeek V4 Pro 0423 | Leader |
|---|---|---|---|
| AA Agentic Index | Not measured | 26.3 | Only DeepSeek V4 Pro 0423 measured |
| Design Arena: agents building web apps | 1317 | 1000 | Claude Opus 5.5 |
| Design Arena: agents building full-stack apps | Not measured | 948 | Only DeepSeek V4 Pro 0423 measured |
| Design Arena: agents building mobile apps | 1310 | Not measured | Only Claude Opus 5.5 measured |
| Design Arena: agents building Godot games | Not measured | 1059 | Only DeepSeek V4 Pro 0423 measured |
| Design Arena: spreadsheets | 1352 | Not measured | Only Claude Opus 5.5 measured |
| LiveBench research | 85.0% | Not measured | Only Claude Opus 5.5 measured |
| LiveBench browser | 80.0% | Not measured | Only Claude Opus 5.5 measured |
| LiveBench long agentic | 85.0% | Not measured | Only Claude Opus 5.5 measured |
| SREBench (Vals AI) | 33.6% | Not measured | Only Claude Opus 5.5 measured |
| Finance Agent (Vals AI) | 58.6% | 44.1% | Claude Opus 5.5 |
| Tax Agent Bench (Vals AI) | 45.6% | 25.2% | Claude Opus 5.5 |
| Legal Research Bench (Vals AI) | 50.5% | 23.1% | Claude Opus 5.5 |
| Harvey's Legal Agent Benchmark (Vals AI) | 9.2% | Not measured | Only Claude Opus 5.5 measured |
| Excel Modeling Benchmark (Vals AI) | 75.9% | 51.6% | Claude Opus 5.5 |
| BioMysteryBench (Vals AI) | 79.3% | Not measured | Only Claude Opus 5.5 measured |
| Terminal-Bench-Science (Vals AI) | 47.1% | Not measured | Only Claude Opus 5.5 measured |
| Vals Science Index | 58.7% | Not measured | Only Claude Opus 5.5 measured |
| Time Horizon Index (Vals AI) | 91.3% | Not measured | Only Claude Opus 5.5 measured |
| CUA-bench (Vals AI) | 14.0% | Not measured | Only Claude Opus 5.5 measured |
| Robo-bench (Vals AI) | 14.6% | Not measured | Only Claude Opus 5.5 measured |
| APEX-Agents | 73.5% | Not measured | Only Claude Opus 5.5 measured |
| Remote Labor Index | 21.3% | Not measured | Only Claude Opus 5.5 measured |
| SpireClimb | 3.3% | Not measured | Only Claude Opus 5.5 measured |
| Vending-Bench 2 | $9,235 | $3,285 | Claude Opus 5.5 |
| LMArena Search | 1213 | Not measured | Only Claude Opus 5.5 measured |
| Neither model has a result on the other 15 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index51
| Benchmark | Claude Opus 5.5 | DeepSeek V4 Pro 0423 | Leader |
|---|---|---|---|
| GPQA Diamond | Not measured | 89.4% | Only DeepSeek V4 Pro 0423 measured |
| LiveBench reasoning | 92.2% | Not measured | Only Claude Opus 5.5 measured |
| MysteryMechanism (Vals AI) | 49.5% | Not measured | Only Claude Opus 5.5 measured |
| Humanity's Last Exam (Artificial Analysis run) | 61.4% | Not measured | Only Claude Opus 5.5 measured |
| GPQA Diamond (Epoch AI run) | 90.6% | 90.9% | DeepSeek V4 Pro 0423 |
| ARC-AGI | 98.5% | Not measured | Only Claude Opus 5.5 measured |
| ARC-AGI-2 | 93.3% | Not measured | Only Claude Opus 5.5 measured |
| Chess puzzles | 67.0% | 19.0% | Claude Opus 5.5 |
| Mystery game puzzles | 71.0% | 17.0% | Claude Opus 5.5 |
| EBR-bench | 71.4% | Not measured | Only Claude Opus 5.5 measured |
| LMArena Text: hard prompts | 1536 | 1461 | Claude Opus 5.5 |
| LMArena Text: expert | 1549 | 1463 | Claude Opus 5.5 |
| LMArena Text: hard prompts in English | 1535 | 1466 | Claude Opus 5.5 |
| LMArena Vision: diagrams | 1345 | Not measured | Only Claude Opus 5.5 measured |
| LMArena Vision: homework | 1362 | Not measured | Only Claude Opus 5.5 measured |
| Kagi LLM Benchmark | Not measured | 53.5% | Only DeepSeek V4 Pro 0423 measured |
| Neither model has a result on the other 6 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | Claude Opus 5.5 | DeepSeek V4 Pro 0423 | Leader |
|---|---|---|---|
| OTIS Mock AIME | 100.0% | 96.7% | Claude Opus 5.5 |
| FrontierMath, tiers 1 to 3 | 91.2% | 45.3% | Claude Opus 5.5 |
| FrontierMath, tier 4 | 95.0% | 2.4% | Claude Opus 5.5 |
| ProofBench | 100.0% | 16.0% | Claude Opus 5.5 |
| LMArena Text: math | 1518 | 1443 | Claude Opus 5.5 |
| LMArena Text: mathematical work | 1516 | 1455 | Claude Opus 5.5 |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | Claude Opus 5.5 | DeepSeek V4 Pro 0423 | Leader |
|---|---|---|---|
| MMLU Pro | Not measured | 87.3% | Only DeepSeek V4 Pro 0423 measured |
| LegalBench (Vals AI) | Not measured | 80.3% | Only DeepSeek V4 Pro 0423 measured |
| CaseLaw (Vals AI) | Not measured | 59.4% | Only DeepSeek V4 Pro 0423 measured |
| CorpFin (Vals AI) | Not measured | 61.4% | Only DeepSeek V4 Pro 0423 measured |
| TaxEval (Vals AI) | Not measured | 72.1% | Only DeepSeek V4 Pro 0423 measured |
| MedCode (Vals AI) | 49.8% | 40.5% | Claude Opus 5.5 |
| SimpleQA Verified | 72.2% | 47.0% | Claude Opus 5.5 |
| LMArena Text: science | 1524 | 1470 | Claude Opus 5.5 |
| LMArena Text: medicine and healthcare | 1509 | 1466 | Claude Opus 5.5 |
| LMArena Text: legal and government | 1518 | 1464 | Claude Opus 5.5 |
| LMArena Text: business and finance | 1494 | 1443 | Claude Opus 5.5 |
| FACTS Benchmark Suite | 65.3% | Not measured | Only Claude Opus 5.5 measured |
| Neither model has a result on the other 6 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index70
| Benchmark | Claude Opus 5.5 | DeepSeek V4 Pro 0423 | Leader |
|---|---|---|---|
| Design Arena: websites | 1336 | 1234 | Claude Opus 5.5 |
| Design Arena: UI components | 1392 | 1222 | Claude Opus 5.5 |
| Design Arena: game dev | 1458 | 1229 | Claude Opus 5.5 |
| Design Arena: data viz | 1397 | 1203 | Claude Opus 5.5 |
| Design Arena: 3D | 1477 | 1254 | Claude Opus 5.5 |
| Design Arena: all code categories | 1390 | 1240 | Claude Opus 5.5 |
| Design Arena: SVG | 1333 | 1140 | Claude Opus 5.5 |
| Design Arena: ASCII art | Not measured | 1149 | Only DeepSeek V4 Pro 0423 measured |
| LiveBench design | 86.9% | Not measured | Only Claude Opus 5.5 measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index180
| Benchmark | Claude Opus 5.5 | DeepSeek V4 Pro 0423 | Leader |
|---|---|---|---|
| Vals Index | 70.2% | Not measured | Only Claude Opus 5.5 measured |
| LiveBench data analysis | 80.3% | Not measured | Only Claude Opus 5.5 measured |
| Public Benefits Bench (Vals AI) | 70.6% | 62.9% | Claude Opus 5.5 |
| SAGE (Vals AI) | 45.8% | Not measured | Only Claude Opus 5.5 measured |
| MedScribe (Vals AI) | 91.4% | 75.1% | Claude Opus 5.5 |
| Long context reasoning (AA-LCR) | 84.7% | Not measured | Only Claude Opus 5.5 measured |
| DTBench | 98.9% | 90.7% | Claude Opus 5.5 |
| LMCA | 68.2% | 41.2% | Claude Opus 5.5 |
| Surface Evolver Bench | Not measured | 40.0% | Only DeepSeek V4 Pro 0423 measured |
| Furniture assembly | 83.3% | Not measured | Only Claude Opus 5.5 measured |
| CL-bench Life | Not measured | 13.5% | Only DeepSeek V4 Pro 0423 measured |
| LMArena Text | 1516 | 1451 | Claude Opus 5.5 |
| LMArena Text: instruction following | 1537 | 1445 | Claude Opus 5.5 |
| LMArena Text: creative writing | 1535 | 1446 | Claude Opus 5.5 |
| LMArena Vision | 1321 | Not measured | Only Claude Opus 5.5 measured |
| LMArena Text: English | 1519 | 1459 | Claude Opus 5.5 |
| LMArena Text: non-English | 1507 | 1439 | Claude Opus 5.5 |
| LMArena Text: Chinese | 1582 | 1481 | Claude Opus 5.5 |
| LMArena Text: German | Not measured | 1458 | Only DeepSeek V4 Pro 0423 measured |
| LMArena Text: Japanese | 1534 | 1446 | Claude Opus 5.5 |
| LMArena Text: Korean | Not measured | 1409 | Only DeepSeek V4 Pro 0423 measured |
| LMArena Text: French | 1493 | 1473 | Claude Opus 5.5 |
| LMArena Text: Spanish | 1508 | 1457 | Claude Opus 5.5 |
| LMArena Text: Russian | 1517 | 1453 | Claude Opus 5.5 |
| LMArena Text: Polish | Not measured | 1461 | Only DeepSeek V4 Pro 0423 measured |
| LMArena Text: multi-turn | 1501 | 1468 | Claude Opus 5.5 |
| LMArena Text: longer queries | 1532 | 1458 | Claude Opus 5.5 |
| LMArena Text: writing and language | 1532 | 1447 | Claude Opus 5.5 |
| LMArena Text: entertainment and media | 1515 | 1431 | Claude Opus 5.5 |
| LMArena Vision: English | 1317 | Not measured | Only Claude Opus 5.5 measured |
| LMArena Vision: reading text | 1326 | Not measured | Only Claude Opus 5.5 measured |
| LMArena Vision: creative writing | 1320 | Not measured | Only Claude Opus 5.5 measured |
| Neither model has a result on the other 14 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Opus 5.5 | DeepSeek V4 Pro 0423 | 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 Pro 0423 costs less
Repository review
50K input + 3K output tokens
DeepSeek V4 Pro 0423 costs less
Agent loop
200K input + 10K output tokens
DeepSeek V4 Pro 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 | Anthropic Claude Opus 5.5 | DeepSeek V4 Pro 0423 |
|---|---|---|
| Maker | Anthropic | DeepSeek |
| Weights | No public weights listed | Open weights |
| Released | September 22, 2026 | April 24, 2026 |
| Context window | 1M | 1.05M |
| Input $/Mtok | $4.00 | $1.225 |
| Output $/Mtok | $20.00 | $2.716 |
| Coding index | 88.8 | 38.7 |
| Independent measurements behind it | 5 | 5 |
| Cost per solved task | Not computable | $0.57 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Opus 5.5 better than DeepSeek V4 Pro 0423 for coding?
Pick Claude Opus 5.5 for coding: it scores 88.8 on the Vibe Coding Index against 38.7 for DeepSeek V4 Pro 0423. Pick DeepSeek V4 Pro 0423 for output tokens 7.4x cheaper ($2.716 vs $20.00 per million) and a larger context window (1.05M against 1M tokens).
Which is cheaper, Claude Opus 5.5 or DeepSeek V4 Pro 0423?
Claude Opus 5.5 costs $4.00 per million input tokens and $20.00 per million output tokens; DeepSeek V4 Pro 0423 costs $1.225 and $2.716. Cost per solved task is known for DeepSeek V4 Pro 0423 only.
Which has the bigger context window, Claude Opus 5.5 or DeepSeek V4 Pro 0423?
DeepSeek V4 Pro 0423, with 1.05M tokens against 1M.
How many benchmarks is the Claude Opus 5.5 vs DeepSeek V4 Pro 0423 comparison based on?
63 benchmarks have a result for both models as of October 21, 2026. Claude Opus 5.5's coding index rests on 5 independent benchmarks and DeepSeek V4 Pro 0423's on 5. Where only one model has a result, the page says so instead of naming a winner.