DeepSeek V3.1 Terminus vs gpt-oss-120b
DeepSeek V3.1 Terminus leads gpt-oss-120b on the Artificial Analysis Intelligence Index, 14.8 to 11.6, and gpt-oss-120b costs 2.0x less per output token ($0.50 vs $1.0142 per million). Updated October 22, 2026; 44 benchmarks have a result for both.
DeepSeek V3.1 Terminus or gpt-oss-120b: which to pick
Neither model has a coding score yet, so the two cannot be ranked on coding.
Pick DeepSeek V3.1 Terminus for a larger context window (164K against 131K tokens) and work measured by LiveCodeBench (Artificial Analysis run) or τ²-Bench Telecom, where it leads.
- Shared results
- 44
- DeepSeek V3.1 Terminus only
- 1
- gpt-oss-120b only
- 41
- 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
No call
Neither has a coding score yet.
One side not measured
Intelligence
AA Intelligence Index
DeepSeek V3.1 Terminus
DeepSeek V3.1 Terminus leads, 14.8 against 11.6.
Same board, both measured
Agentic work
AA Agentic Index
DeepSeek V3.1 Terminus
DeepSeek V3.1 Terminus leads, 6.8 against 3.7.
Same board, both measured
Reasoning
GPQA Diamond
No call
Only gpt-oss-120b has a GPQA Diamond result, 78.5%.
Directional only
Math
AIME
No call
Only gpt-oss-120b has a AIME result, 92.6%.
Directional only
Knowledge
MMLU Pro
No call
Only gpt-oss-120b has a MMLU Pro result, 79.2%.
Directional only
Web design
Design Arena: websites
DeepSeek V3.1 Terminus
DeepSeek V3.1 Terminus leads, 1187 against 968.
Same board, both measured
Long documents
Listed context window
DeepSeek V3.1 Terminus
DeepSeek V3.1 Terminus takes 164K tokens against 131K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
gpt-oss-120b
DeepSeek V3.1 Terminus $0.0008, gpt-oss-120b $0.0003 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only gpt-oss-120b has the number, $0.51.
Directional only
At a glance
- Coding index
- DeepSeek V3.1 Terminus not benchmarked, gpt-oss-120b not benchmarked.
- Widest category
- Web design, 26.0 points apart on average over 6 shared benchmarks.
- Widest single gap
- Design Arena: UI components: DeepSeek V3.1 Terminus 1180 against gpt-oss-120b 924, 32.0 points apart on a 0 to 100 scale.
- Output price
- DeepSeek V3.1 Terminus $1.0142 against gpt-oss-120b $0.50 per million output tokens, 2.0x apart.
- Context window
- DeepSeek V3.1 Terminus takes 164K tokens, gpt-oss-120b 131K.
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 V3.1 Terminus | Bars | gpt-oss-120b | Ties |
|---|---|---|---|---|
| Coding | 6 | 1 | ||
| Intelligence | 1 | 0 | ||
| Agentic work | 1 | 1 | ||
| Reasoning | 3 | 2 | ||
| Math | 1 | 2 | ||
| Knowledge | 5 | 0 | ||
| Web design | 6 | 0 | ||
| General | 14 | 1 | ||
| All shared boards | 37 | 7 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index61
| Benchmark | DeepSeek V3.1 Terminus | gpt-oss-120b | Leader |
|---|---|---|---|
| Aider polyglot | Not measured | 41.8% | Only gpt-oss-120b measured |
| SWE-bench Verified | Not measured | 26.0% | Only gpt-oss-120b measured |
| AA Coding Index | 43.5 | 30.4 | DeepSeek V3.1 Terminus |
| LiveCodeBench (Vals AI) | Not measured | 83.2% | Only gpt-oss-120b measured |
| SWE-bench Verified (Vals AI) | Not measured | 33.6% | Only gpt-oss-120b measured |
| LiveCodeBench (Artificial Analysis run) | 79.8% | 87.8% | gpt-oss-120b |
| SciCode | 38.0% | 34.0% | DeepSeek V3.1 Terminus |
| Terminal-Bench Hard (Artificial Analysis run) | 31.8% | 23.5% | DeepSeek V3.1 Terminus |
| Terminal-Bench | Not measured | 18.7% | Only gpt-oss-120b measured |
| WeirdML | Not measured | 48.2% | Only gpt-oss-120b measured |
| ALE-Bench | 745.2 | 575.6 | DeepSeek V3.1 Terminus |
| LMArena Text: coding | 1425 | 1379 | DeepSeek V3.1 Terminus |
| LMArena Text: software and IT | 1426 | 1387 | DeepSeek V3.1 Terminus |
| SciCode | Not measured | 7.7% | Only gpt-oss-120b measured |
| Neither model has a result on the other 29 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | DeepSeek V3.1 Terminus | gpt-oss-120b | Leader |
|---|---|---|---|
| AA Intelligence Index | 14.8 | 11.6 | DeepSeek V3.1 Terminus |
| Epoch Capabilities Index | Not measured | 139.8 | Only gpt-oss-120b measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index11
| Benchmark | DeepSeek V3.1 Terminus | gpt-oss-120b | Leader |
|---|---|---|---|
| AA Agentic Index | 6.8 | 3.7 | DeepSeek V3.1 Terminus |
| τ²-Bench Telecom | 37.1% | 65.8% | gpt-oss-120b |
| APEX-Agents | Not measured | 4.4% | Only gpt-oss-120b measured |
| METR time horizons | Not measured | 56.6% | Only gpt-oss-120b measured |
| Vending-Bench 2 | Not measured | -$22 | Only gpt-oss-120b measured |
| BrowseComp-Plus | Not measured | 67.0% | Only gpt-oss-120b measured |
| Neither model has a result on the other 36 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index32
| Benchmark | DeepSeek V3.1 Terminus | gpt-oss-120b | Leader |
|---|---|---|---|
| GPQA Diamond | Not measured | 78.5% | Only gpt-oss-120b measured |
| GPQA Diamond (Artificial Analysis run) | 79.2% | 78.2% | DeepSeek V3.1 Terminus |
| Humanity's Last Exam (Artificial Analysis run) | 16.4% | 19.6% | gpt-oss-120b |
| GPQA Diamond (Epoch AI run) | Not measured | 75.8% | Only gpt-oss-120b measured |
| SimpleBench | Not measured | 22.1% | Only gpt-oss-120b measured |
| Mystery game puzzles | Not measured | 2.0% | Only gpt-oss-120b measured |
| LMArena Text: hard prompts | 1426 | 1364 | DeepSeek V3.1 Terminus |
| LMArena Text: expert | Not measured | 1356 | Only gpt-oss-120b measured |
| LMArena Text: hard prompts in English | 1432 | 1368 | DeepSeek V3.1 Terminus |
| Kagi LLM Benchmark | 57.4% | 58.6% | gpt-oss-120b |
| Neither model has a result on the other 13 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index12
| Benchmark | DeepSeek V3.1 Terminus | gpt-oss-120b | Leader |
|---|---|---|---|
| AIME | Not measured | 92.6% | Only gpt-oss-120b measured |
| MATH 500 (Vals AI) | Not measured | 94.8% | Only gpt-oss-120b measured |
| MGSM (Vals AI) | Not measured | 92.0% | Only gpt-oss-120b measured |
| AA Math Index | 89.7 | 93.4 | gpt-oss-120b |
| AIME 2025 (Artificial Analysis run) | 89.7% | 93.4% | gpt-oss-120b |
| OTIS Mock AIME | Not measured | 88.9% | Only gpt-oss-120b measured |
| LMArena Text: math | 1402 | 1389 | DeepSeek V3.1 Terminus |
| LMArena Text: mathematical work | Not measured | 1386 | Only gpt-oss-120b measured |
| MathArena | Not measured | 15.1% | Only gpt-oss-120b measured |
| Neither model has a result on the other 5 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index50
| Benchmark | DeepSeek V3.1 Terminus | gpt-oss-120b | Leader |
|---|---|---|---|
| MMLU Pro | Not measured | 79.2% | Only gpt-oss-120b measured |
| LegalBench (Vals AI) | Not measured | 75.9% | Only gpt-oss-120b measured |
| CaseLaw (Vals AI) | Not measured | 48.8% | Only gpt-oss-120b measured |
| CorpFin (Vals AI) | Not measured | 58.2% | Only gpt-oss-120b measured |
| TaxEval (Vals AI) | Not measured | 71.6% | Only gpt-oss-120b measured |
| MedQA (Vals AI) | Not measured | 91.4% | Only gpt-oss-120b measured |
| MMLU Pro (Artificial Analysis run) | 85.1% | 80.8% | DeepSeek V3.1 Terminus |
| LMArena Text: science | 1451 | 1382 | DeepSeek V3.1 Terminus |
| LMArena Text: medicine and healthcare | 1468 | 1388 | DeepSeek V3.1 Terminus |
| LMArena Text: legal and government | 1457 | 1355 | DeepSeek V3.1 Terminus |
| LMArena Text: business and finance | 1414 | 1359 | DeepSeek V3.1 Terminus |
| PRBench Finance | Not measured | 43.8% | Only gpt-oss-120b measured |
| PRBench Legal | Not measured | 40.2% | Only gpt-oss-120b measured |
| Neither model has a result on the other 7 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | DeepSeek V3.1 Terminus | gpt-oss-120b | Leader |
|---|---|---|---|
| Design Arena: websites | 1187 | 968 | DeepSeek V3.1 Terminus |
| Design Arena: UI components | 1180 | 924 | DeepSeek V3.1 Terminus |
| Design Arena: game dev | 1131 | 991 | DeepSeek V3.1 Terminus |
| Design Arena: data viz | 1168 | 987 | DeepSeek V3.1 Terminus |
| Design Arena: 3D | 1141 | 901 | DeepSeek V3.1 Terminus |
| Design Arena: all code categories | 1175 | 962 | DeepSeek V3.1 Terminus |
| Design Arena: SVG | 1065 | Not measured | Only DeepSeek V3.1 Terminus measured |
| Neither model has a result on the other 2 boards here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index141
| Benchmark | DeepSeek V3.1 Terminus | gpt-oss-120b | Leader |
|---|---|---|---|
| IFBench | 57.0% | 69.0% | gpt-oss-120b |
| Long context reasoning (AA-LCR) | 69.3% | 52.0% | DeepSeek V3.1 Terminus |
| DTBench | 81.3% | 76.3% | DeepSeek V3.1 Terminus |
| LMCA | 28.6% | 22.1% | DeepSeek V3.1 Terminus |
| Fiction.LiveBench | Not measured | 44.4% | Only gpt-oss-120b measured |
| Creative writing (Lech Mazur) | Not measured | 77.1% | Only gpt-oss-120b measured |
| Surface Evolver Bench | Not measured | 25.0% | Only gpt-oss-120b measured |
| LMArena Text | 1419 | 1366 | DeepSeek V3.1 Terminus |
| LMArena Text: instruction following | 1404 | 1318 | DeepSeek V3.1 Terminus |
| LMArena Text: creative writing | 1403 | 1274 | DeepSeek V3.1 Terminus |
| LMArena Text: English | 1429 | 1375 | DeepSeek V3.1 Terminus |
| LMArena Text: non-English | 1408 | 1351 | DeepSeek V3.1 Terminus |
| LMArena Text: Chinese | Not measured | 1385 | Only gpt-oss-120b measured |
| LMArena Text: German | Not measured | 1353 | Only gpt-oss-120b measured |
| LMArena Text: Japanese | Not measured | 1331 | Only gpt-oss-120b measured |
| LMArena Text: Korean | Not measured | 1282 | Only gpt-oss-120b measured |
| LMArena Text: French | Not measured | 1370 | Only gpt-oss-120b measured |
| LMArena Text: Spanish | Not measured | 1389 | Only gpt-oss-120b measured |
| LMArena Text: Russian | 1435 | 1343 | DeepSeek V3.1 Terminus |
| LMArena Text: Polish | 1427 | 1353 | DeepSeek V3.1 Terminus |
| LMArena Text: multi-turn | 1411 | 1340 | DeepSeek V3.1 Terminus |
| LMArena Text: longer queries | 1422 | 1319 | DeepSeek V3.1 Terminus |
| LMArena Text: writing and language | 1409 | 1306 | DeepSeek V3.1 Terminus |
| LMArena Text: entertainment and media | 1391 | 1292 | DeepSeek V3.1 Terminus |
| MultiChallenge | Not measured | 45.3% | Only gpt-oss-120b measured |
| Neither model has a result on the other 23 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | DeepSeek V3.1 Terminus | gpt-oss-120b | 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
gpt-oss-120b costs less
Repository review
50K input + 3K output tokens
gpt-oss-120b costs less
Agent loop
200K input + 10K output tokens
gpt-oss-120b 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 V3.1 Terminus | OpenAI gpt-oss-120b |
|---|---|---|
| Maker | DeepSeek | OpenAI |
| Weights | Open weights | Open weights |
| Released | September 22, 2025 | August 5, 2025 |
| Context window | 164K | 131K |
| Input $/Mtok | $0.3063 | $0.10 |
| Output $/Mtok | $1.0142 | $0.50 |
| Coding index | Not benchmarked | Not benchmarked |
| Independent measurements behind it | 0 | 1 |
| Cost per solved task | Not computable | $0.51 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is DeepSeek V3.1 Terminus better than gpt-oss-120b for coding?
Neither model has a coding score yet, so the two cannot be ranked on coding. Pick DeepSeek V3.1 Terminus for a larger context window (164K against 131K tokens) and work measured by LiveCodeBench (Artificial Analysis run) or τ²-Bench Telecom, where it leads.
Which is cheaper, DeepSeek V3.1 Terminus or gpt-oss-120b?
DeepSeek V3.1 Terminus costs $0.3063 per million input tokens and $1.0142 per million output tokens; gpt-oss-120b costs $0.10 and $0.50. Cost per solved task is known for gpt-oss-120b only.
Which has the bigger context window, DeepSeek V3.1 Terminus or gpt-oss-120b?
DeepSeek V3.1 Terminus, with 164K tokens against 131K.
How many benchmarks is the DeepSeek V3.1 Terminus vs gpt-oss-120b comparison based on?
44 benchmarks have a result for both models as of October 22, 2026. DeepSeek V3.1 Terminus's coding index rests on 0 independent benchmarks and gpt-oss-120b's on 1. Where only one model has a result, the page says so instead of naming a winner.