Claude Haiku 5.5 vs DeepSeek V3.1 Terminus
Claude Haiku 5.5 leads DeepSeek V3.1 Terminus on the Artificial Analysis Intelligence Index, 43.4 to 14.8, and Claude Haiku 5.5 costs 2.0x less per output token ($0.50 vs $1.0142 per million). Updated October 22, 2026; 12 benchmarks have a result for both.
Claude Haiku 5.5 or DeepSeek V3.1 Terminus: which to pick
Only Claude Haiku 5.5 has a coding score, 70.7 on the Vibe Coding Index; DeepSeek V3.1 Terminus has none, so the two cannot be ranked on coding.
Compare them on price, context and the boards below.
- Shared results
- 12
- Claude Haiku 5.5 only
- 51
- DeepSeek V3.1 Terminus only
- 33
- Like-for-like categories
- 5 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
Only Claude Haiku 5.5 has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
Claude Haiku 5.5
Claude Haiku 5.5 leads, 43.4 against 14.8.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only DeepSeek V3.1 Terminus has a AA Agentic Index result, 6.8.
Directional only
Web design
Design Arena: websites
Claude Haiku 5.5
Claude Haiku 5.5 leads, 1262 against 1187.
Same board, both measured
General
Vals Index
No call
Only Claude Haiku 5.5 has a Vals Index result, 58.7%.
Directional only
Long documents
Listed context window
Claude Haiku 5.5
Claude Haiku 5.5 takes 1M tokens against 164K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Claude Haiku 5.5
Claude Haiku 5.5 $0.0003, DeepSeek V3.1 Terminus $0.0008 per turn.
List prices
At a glance
- Coding index
- Claude Haiku 5.5 70.7 from 5 benchmarks, DeepSeek V3.1 Terminus not benchmarked.
- Widest category
- Intelligence, 28.6 points apart on average over 1 shared benchmark.
- Widest single gap
- AA Intelligence Index: Claude Haiku 5.5 43.4 against DeepSeek V3.1 Terminus 14.8, 28.6 points apart on a 0 to 100 scale.
- Output price
- Claude Haiku 5.5 $0.50 against DeepSeek V3.1 Terminus $1.0142 per million output tokens, 2.0x apart.
- Context window
- Claude Haiku 5.5 takes 1M tokens, DeepSeek V3.1 Terminus 164K.
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 Haiku 5.5 | Bars | DeepSeek V3.1 Terminus | Ties |
|---|---|---|---|---|
| Coding | 1 | 0 | ||
| Intelligence | 1 | 0 | ||
| Reasoning | 1 | 0 | ||
| Web design | 6 | 0 | ||
| General | 3 | 0 | ||
| All shared boards | 12 | 0 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index10
| Benchmark | Claude Haiku 5.5 | DeepSeek V3.1 Terminus | Leader |
|---|---|---|---|
| LiveBench coding | 91.4% | Not measured | Only Claude Haiku 5.5 measured |
| LMArena WebDev | 1586 | Not measured | Only Claude Haiku 5.5 measured |
| AA Coding Index | Not measured | 43.5 | Only DeepSeek V3.1 Terminus measured |
| Terminal-Bench 4 (Vals AI) | 36.4% | Not measured | Only Claude Haiku 5.5 measured |
| Vibe Code Bench (Vals AI) | 90.4% | Not measured | Only Claude Haiku 5.5 measured |
| Code migration (Vals AI) | 44.6% | Not measured | Only Claude Haiku 5.5 measured |
| ProgramBench (Vals AI) | 2.5% | Not measured | Only Claude Haiku 5.5 measured |
| IOI (Vals AI) | 47.3% | Not measured | Only Claude Haiku 5.5 measured |
| SWE-bench Multimodal (Vals AI) | 44.0% | Not measured | Only Claude Haiku 5.5 measured |
| Vibe Code Bench 1-100 (Vals AI) | 20.4% | Not measured | Only Claude Haiku 5.5 measured |
| CyberBench (Vals AI) | 75.5% | Not measured | Only Claude Haiku 5.5 measured |
| LiveCodeBench (Artificial Analysis run) | Not measured | 79.8% | Only DeepSeek V3.1 Terminus measured |
| SciCode | 55.0% | 38.0% | Claude Haiku 5.5 |
| Terminal-Bench Hard (Artificial Analysis run) | Not measured | 31.8% | Only DeepSeek V3.1 Terminus measured |
| FrontierCode | 46.4% | Not measured | Only Claude Haiku 5.5 measured |
| FrontierSWE | 43.8% | Not measured | Only Claude Haiku 5.5 measured |
| ALE-Bench | Not measured | 745.2 | Only DeepSeek V3.1 Terminus measured |
| LMArena Text: coding | Not measured | 1425 | Only DeepSeek V3.1 Terminus measured |
| LMArena Text: software and IT | Not measured | 1426 | Only DeepSeek V3.1 Terminus measured |
| LMArena WebDev: React | 1605 | Not measured | Only Claude Haiku 5.5 measured |
| LMArena WebDev: HTML | 1569 | Not measured | Only Claude Haiku 5.5 measured |
| SciCode | 9.2% | Not measured | Only Claude Haiku 5.5 measured |
| Neither model has a result on the other 17 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Claude Haiku 5.5 | DeepSeek V3.1 Terminus | Leader |
|---|---|---|---|
| AA Intelligence Index | 43.4 | 14.8 | Claude Haiku 5.5 |
| Epoch Capabilities Index | 159.3 | Not measured | Only Claude Haiku 5.5 measured |
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index16 boards, none shared
| Benchmark | Claude Haiku 5.5 | DeepSeek V3.1 Terminus | Leader |
|---|---|---|---|
| AA Agentic Index | Not measured | 6.8 | Only DeepSeek V3.1 Terminus measured |
| LiveBench research | 81.9% | Not measured | Only Claude Haiku 5.5 measured |
| LiveBench browser | 80.0% | Not measured | Only Claude Haiku 5.5 measured |
| LiveBench long agentic | 57.6% | Not measured | Only Claude Haiku 5.5 measured |
| SREBench (Vals AI) | 5.7% | Not measured | Only Claude Haiku 5.5 measured |
| Finance Agent (Vals AI) | 54.1% | Not measured | Only Claude Haiku 5.5 measured |
| Tax Agent Bench (Vals AI) | 31.9% | Not measured | Only Claude Haiku 5.5 measured |
| Legal Research Bench (Vals AI) | 43.3% | Not measured | Only Claude Haiku 5.5 measured |
| Harvey's Legal Agent Benchmark (Vals AI) | 4.2% | Not measured | Only Claude Haiku 5.5 measured |
| Excel Modeling Benchmark (Vals AI) | 59.0% | Not measured | Only Claude Haiku 5.5 measured |
| BioMysteryBench (Vals AI) | 70.4% | Not measured | Only Claude Haiku 5.5 measured |
| Terminal-Bench-Science (Vals AI) | 10.0% | Not measured | Only Claude Haiku 5.5 measured |
| Vals Science Index | 38.5% | Not measured | Only Claude Haiku 5.5 measured |
| τ²-Bench Telecom | Not measured | 37.1% | Only DeepSeek V3.1 Terminus measured |
| APEX-Agents | 56.1% | Not measured | Only Claude Haiku 5.5 measured |
| Vending-Bench 2 | $3,602 | Not measured | Only Claude Haiku 5.5 measured |
| Neither model has a result on the other 25 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Claude Haiku 5.5 | DeepSeek V3.1 Terminus | Leader |
|---|---|---|---|
| LiveBench reasoning | 82.4% | Not measured | Only Claude Haiku 5.5 measured |
| MysteryMechanism (Vals AI) | 35.1% | Not measured | Only Claude Haiku 5.5 measured |
| GPQA Diamond (Artificial Analysis run) | Not measured | 79.2% | Only DeepSeek V3.1 Terminus measured |
| Humanity's Last Exam (Artificial Analysis run) | 44.4% | 16.4% | Claude Haiku 5.5 |
| GPQA Diamond (Epoch AI run) | 89.6% | Not measured | Only Claude Haiku 5.5 measured |
| ARC-AGI | 89.0% | Not measured | Only Claude Haiku 5.5 measured |
| ARC-AGI-2 | 61.3% | Not measured | Only Claude Haiku 5.5 measured |
| Chess puzzles | 55.0% | Not measured | Only Claude Haiku 5.5 measured |
| Mystery game puzzles | 30.0% | Not measured | Only Claude Haiku 5.5 measured |
| EBR-bench | 43.8% | Not measured | Only Claude Haiku 5.5 measured |
| LMArena Text: hard prompts | Not measured | 1426 | Only DeepSeek V3.1 Terminus measured |
| LMArena Text: hard prompts in English | Not measured | 1432 | Only DeepSeek V3.1 Terminus measured |
| Kagi LLM Benchmark | Not measured | 57.4% | Only DeepSeek V3.1 Terminus measured |
| Neither model has a result on the other 9 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index7 boards, none shared
| Benchmark | Claude Haiku 5.5 | DeepSeek V3.1 Terminus | Leader |
|---|---|---|---|
| AA Math Index | Not measured | 89.7 | Only DeepSeek V3.1 Terminus measured |
| AIME 2025 (Artificial Analysis run) | Not measured | 89.7% | Only DeepSeek V3.1 Terminus measured |
| OTIS Mock AIME | 98.9% | Not measured | Only Claude Haiku 5.5 measured |
| FrontierMath, tiers 1 to 3 | 75.1% | Not measured | Only Claude Haiku 5.5 measured |
| FrontierMath, tier 4 | 46.3% | Not measured | Only Claude Haiku 5.5 measured |
| ProofBench | 89.0% | Not measured | Only Claude Haiku 5.5 measured |
| LMArena Text: math | Not measured | 1402 | Only DeepSeek V3.1 Terminus measured |
| Neither model has a result on the other 6 boards here | |||
KnowledgeDirectional onlyPublic boards, shown as published, kept out of the index7 boards, none shared
| Benchmark | Claude Haiku 5.5 | DeepSeek V3.1 Terminus | Leader |
|---|---|---|---|
| MedCode (Vals AI) | 51.5% | Not measured | Only Claude Haiku 5.5 measured |
| MMLU Pro (Artificial Analysis run) | Not measured | 85.1% | Only DeepSeek V3.1 Terminus measured |
| SimpleQA Verified | 23.8% | Not measured | Only Claude Haiku 5.5 measured |
| LMArena Text: science | Not measured | 1451 | Only DeepSeek V3.1 Terminus measured |
| LMArena Text: medicine and healthcare | Not measured | 1468 | Only DeepSeek V3.1 Terminus measured |
| LMArena Text: legal and government | Not measured | 1457 | Only DeepSeek V3.1 Terminus measured |
| LMArena Text: business and finance | Not measured | 1414 | Only DeepSeek V3.1 Terminus measured |
| Neither model has a result on the other 11 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | Claude Haiku 5.5 | DeepSeek V3.1 Terminus | Leader |
|---|---|---|---|
| Design Arena: websites | 1262 | 1187 | Claude Haiku 5.5 |
| Design Arena: UI components | 1291 | 1182 | Claude Haiku 5.5 |
| Design Arena: game dev | 1313 | 1131 | Claude Haiku 5.5 |
| Design Arena: data viz | 1294 | 1168 | Claude Haiku 5.5 |
| Design Arena: 3D | 1342 | 1141 | Claude Haiku 5.5 |
| Design Arena: all code categories | 1278 | 1175 | Claude Haiku 5.5 |
| Design Arena: SVG | Not measured | 1065 | Only DeepSeek V3.1 Terminus measured |
| LiveBench design | 83.1% | Not measured | Only Claude Haiku 5.5 measured |
| Neither model has a result on the other 1 board here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index30
| Benchmark | Claude Haiku 5.5 | DeepSeek V3.1 Terminus | Leader |
|---|---|---|---|
| Vals Index | 58.7% | Not measured | Only Claude Haiku 5.5 measured |
| LiveBench data analysis | 53.1% | Not measured | Only Claude Haiku 5.5 measured |
| Public Benefits Bench (Vals AI) | 63.2% | Not measured | Only Claude Haiku 5.5 measured |
| SAGE (Vals AI) | 45.8% | Not measured | Only Claude Haiku 5.5 measured |
| MedScribe (Vals AI) | 89.5% | Not measured | Only Claude Haiku 5.5 measured |
| IFBench | Not measured | 57.0% | Only DeepSeek V3.1 Terminus measured |
| Long context reasoning (AA-LCR) | 82.7% | 69.3% | Claude Haiku 5.5 |
| DTBench | 95.0% | 81.3% | Claude Haiku 5.5 |
| LMCA | 51.1% | 28.6% | Claude Haiku 5.5 |
| Furniture assembly | 47.5% | Not measured | Only Claude Haiku 5.5 measured |
| LMArena Text | Not measured | 1419 | Only DeepSeek V3.1 Terminus measured |
| LMArena Text: instruction following | Not measured | 1404 | Only DeepSeek V3.1 Terminus measured |
| LMArena Text: creative writing | Not measured | 1403 | Only DeepSeek V3.1 Terminus measured |
| LMArena Text: English | Not measured | 1429 | Only DeepSeek V3.1 Terminus measured |
| LMArena Text: non-English | Not measured | 1408 | Only DeepSeek V3.1 Terminus measured |
| LMArena Text: Russian | Not measured | 1435 | Only DeepSeek V3.1 Terminus measured |
| LMArena Text: Polish | Not measured | 1427 | Only DeepSeek V3.1 Terminus measured |
| LMArena Text: multi-turn | Not measured | 1411 | Only DeepSeek V3.1 Terminus measured |
| LMArena Text: longer queries | Not measured | 1422 | Only DeepSeek V3.1 Terminus measured |
| LMArena Text: writing and language | Not measured | 1409 | Only DeepSeek V3.1 Terminus measured |
| LMArena Text: entertainment and media | Not measured | 1391 | Only DeepSeek V3.1 Terminus measured |
| Neither model has a result on the other 25 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Haiku 5.5 | DeepSeek V3.1 Terminus | 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
Claude Haiku 5.5 costs less
Repository review
50K input + 3K output tokens
Claude Haiku 5.5 costs less
Agent loop
200K input + 10K output tokens
Claude Haiku 5.5 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 Haiku 5.5 | DeepSeek V3.1 Terminus |
|---|---|---|
| Maker | Anthropic | DeepSeek |
| Weights | No public weights listed | Open weights |
| Released | October 7, 2026 | September 22, 2025 |
| Context window | 1M | 164K |
| Input $/Mtok | $0.10 | $0.3063 |
| Output $/Mtok | $0.50 | $1.0142 |
| Coding index | 70.7 | Not benchmarked |
| Independent measurements behind it | 5 | 0 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Haiku 5.5 better than DeepSeek V3.1 Terminus for coding?
Only Claude Haiku 5.5 has a coding score, 70.7 on the Vibe Coding Index; DeepSeek V3.1 Terminus has none, so the two cannot be ranked on coding. Compare them on price, context and the boards below.
Which is cheaper, Claude Haiku 5.5 or DeepSeek V3.1 Terminus?
Claude Haiku 5.5 costs $0.10 per million input tokens and $0.50 per million output tokens; DeepSeek V3.1 Terminus costs $0.3063 and $1.0142. Cost per solved task is known for neither of them.
Which has the bigger context window, Claude Haiku 5.5 or DeepSeek V3.1 Terminus?
Claude Haiku 5.5, with 1M tokens against 164K.
How many benchmarks is the Claude Haiku 5.5 vs DeepSeek V3.1 Terminus comparison based on?
12 benchmarks have a result for both models as of October 22, 2026. Claude Haiku 5.5's coding index rests on 5 independent benchmarks and DeepSeek V3.1 Terminus's on 0. Where only one model has a result, the page says so instead of naming a winner.