GPT-6.1 Terra vs Muse Spark 1.2
Full profiles: GPT-6.1 Terra (OpenAI) and Muse Spark 1.2 (Meta): every benchmark, price and rank.
Updated · Data from 7 sources
As of 27 Oct 2026, GPT-6.1 Terra (max) and Muse Spark 1.2 (xhigh) are neck and neck on quality (65.9 vs 63.1, inside the ±8.4 margin of error) and cost about the same, so speed decides it: Muse Spark 1.2 (xhigh) streams 3.2× faster. GPT-6.1 Terra leads in every category we measure both in.
GPT-6.1 Terra benchmarks 
Muse Spark 1.2 benchmarks Which to pick for…
The pick's numbers come first. Category scores on the BenchLeader scale (50 is the average model, 15 points one standard deviation). High confidence means a lead of half a standard deviation or more; under one point is called either.
| Use case | Pick | Why | Confidence |
|---|---|---|---|
| Reasoning | GPT-6.1 Terra | 86 vs 69 category score; CritPt 28.0% vs 17.7% | High |
| Knowledge | GPT-6.1 Terra | 75 vs 67 category score; AA-Omniscience 29.8 vs 27.2 | High |
| Long documents | GPT-6.1 Terra | 66 vs 64 category score; AA-LCR 82.7% vs 79.0% | Medium |
| Images and other media | GPT-6.1 Terra | 68 vs 65 category score | Medium |
| Chat quality (human preference) | – | Only Muse Spark 1.2 has an Arena rating (69 category score) | Not comparable |
| Lowest cost | Either | $2.00 vs $2.00 per 1M blended; agentic coding session $0.080 vs $0.092 | – |
| Fastest first answer | Muse Spark 1.2 | 18.6 s (Muse Spark 1.2 (xhigh)) vs 131.8 s (GPT-6.1 Terra (max)) to the first answer token | – |
| High volume on a budget | Neither flagship | A smaller model is usually the better fit: Cheapest good LLMs, Fastest LLMs | – |
Key differences
- GPT-6.1 Terra (max) and Muse Spark 1.2 (xhigh) are neck and neck on quality (65.9 vs 63.1, within the ±8.4 margin).
- GPT-6.1 Terra (max) is stronger in composite, knowledge, long context, multimodal, reasoning.
- Muse Spark 1.2 (xhigh) is stronger in agents & tools, coding, human preference, maths.
- They cost about the same ($2.00 per 1M blended).
- Muse Spark 1.2 (xhigh) streams 3.2× faster (293 vs 91 tokens per second).
At a glance
| Spec | GPT-6.1 Terra | Muse Spark 1.2 |
|---|---|---|
| Developer | OpenAI | Meta |
| Released | 26 Oct 2026 | 5 Aug 2026 |
| Context window (tokens) | 1,050,000 | 1,048,576 |
| Compared at | GPT-6.1 Terra (max) | Muse Spark 1.2 (xhigh) |
| Open weights | No | No |
| Price in / out / cached input per 1M | $1.00 / $5.00 / $0.050 | $1.25 / $4.25 / $0.150 |
Category by category
Category scores on the BenchLeader scale: 50 is the average evaluated model, 15 points is one standard deviation. A gap under one point is called level.
| Category | GPT-6.1 Terra (max) | Muse Spark 1.2 (xhigh) | Leader |
|---|---|---|---|
| Reasoning | 86.2 | 69.0 | GPT-6.1 Terra |
| Coding | – | 55.0 | not comparable |
| Agents & tools | – | 55.4 | not comparable |
| Maths | – | 67.3 | not comparable |
| Knowledge | 74.5 | 66.6 | GPT-6.1 Terra |
| Human preference | – | 68.6 | not comparable |
| Multimodal | 67.5 | 65.2 | GPT-6.1 Terra |
| Long context | 66.3 | 64.4 | GPT-6.1 Terra |
| Composite | 82.8 | 73.3 | GPT-6.1 Terra |
Where sources disagree
Across the 11 benchmarks both have, GPT-6.1 Terra leads 9, Muse Spark 1.2 leads 2. Every overall index that rates both puts GPT-6.1 Terra ahead.
| Overall index | GPT-6.1 Terra (max) | Muse Spark 1.2 (xhigh) | Leader |
|---|---|---|---|
| BenchLeader Index | 65.9 | 63.1 | neck and neck |
| AA Intelligence Index v4.3.2 | 48.1 | 39.6 | GPT-6.1 Terra |
Each publisher runs its own tasks, harnesses and effort settings, so their overall verdicts can differ; BenchLeader reconciles them on one scale. † measured at another effort setting of the same model (the publisher did not test the one compared here).
Price, speed and latency
List prices blended at three input tokens per output token. Per-task prices use the token counts on the methodology page; suite cost is what Artificial Analysis paid to run its whole Intelligence Index.
| Measure | GPT-6.1 Terra (max) | Muse Spark 1.2 (xhigh) |
|---|---|---|
| Blended price per 1M tokens | $2.00 | $2.00 |
| Input / output per 1M | $1.00 / $5.00 | $1.25 / $4.25 |
| Cached input per 1M | $0.050 | $0.150 |
| Price per task: chat reply | $0.0019 | $0.0018 |
| Price per task: summarize a 30-page report | $0.015 | $0.018 |
| Price per task: code edit | $0.013 | $0.014 |
| Price per task: agentic coding session | $0.080 | $0.092 |
| Price per task: structured extraction | $0.0030 | $0.0034 |
| Cost to run a full benchmark suite | $0.403 | $1.29 |
| Output speed | 91 tok/s | 293 tok/s |
| Time to first answer | 131.8 s | 18.6 s |
| Time to a complete answer | 137.3 s | 20.3 s |
Per token is not per task: on Artificial Analysis' full suite GPT-6.1 Terra (max) cost $0.403 and Muse Spark 1.2 (xhigh) $1.29, because Muse Spark 1.2 (xhigh) used about 3.2× as many tokens for the same work, which a per-token price hides.
Each model is compared at its best-ranked reasoning-effort setting. GPT-6.1 Terra (max) scores 65.9 and takes 132 s to its first answer token; GPT-6.1 Terra (xhigh) scores 65.0 in 18 s, GPT-6.1 Terra (high) scores 64.7 in 7 s. Muse Spark 1.2 (xhigh) scores 63.1 and takes 19 s to its first answer token. Higher effort means more thinking before the answer: better scores, longer waits and more tokens billed. How reasoning effort changes scores and cost.
Every benchmark
89 benchmarks, grouped by category; each name links to the board and its leaders. † measured at another effort setting of the same model, shown for reference and not counted as a win.
| Metric | Publisher | GPT-6.1 Terra (max) | Muse Spark 1.2 (xhigh) |
|---|---|---|---|
| BenchLeader Index | BenchLeader | 65.9 | 63.1 |
| Composite score | BenchLeader | 82.8 | 73.3 |
| Knowledge score | BenchLeader | 74.5 | 66.6 |
| Long context score | BenchLeader | 66.3 | 64.4 |
| Multimodal score | BenchLeader | 67.5 | 65.2 |
| Reasoning score | BenchLeader | 86.2 | 69.0 |
| Agents & tools score | BenchLeader | – | 55.4 |
| Coding score | BenchLeader | – | 55.0 |
| Human preference score | BenchLeader | – | 68.6 |
| Maths score | BenchLeader | – | 67.3 |
| Blended price $/M | BenchLeader | $2.00 | $2.00 |
| Output speed | BenchLeader | 91 tok/s | 293 tok/s |
| Time to first answer | BenchLeader | 131.8 s | 18.6 s |
| Context window | BenchLeader | 1,050,000 tokens | 1,048,576 tokens |
| Reasoning | |||
| SimpleBench | SimpleBench | – | 74.5%† |
| Arena Hard Prompts | Arena (LMArena) | – | 1512 |
| LiveBench 2.0 Reasoning | LiveBench | 88.7%† | – |
| LiveBench 1.0 Reasoning | LiveBench | – | 90.0% |
| GPQA Diamond (AA) | Artificial Analysis | – | 90.4% |
| Humanity's Last Exam (AA) | Artificial Analysis | 46.3% | 45.5% |
| CritPt | Artificial Analysis | 28.0% | 17.7% |
| Chess Puzzles | Epoch AI Benchmarking Hub | – | 27.0% |
| LMCA | Epoch AI Benchmarking Hub | – | 48.4% |
| DTBench | Epoch AI Benchmarking Hub | – | 94.7% |
| Coding | |||
| SciCode | SciCode | – | 57.4% |
| WeirdML | WeirdML | – | 60.3% |
| Arena Coding | Arena (LMArena) | – | 1541 |
| Arena WebDev | Arena (LMArena) | – | 1533 |
| LiveBench 2.0 Coding | LiveBench | 90.8%† | – |
| LiveBench 1.0 Coding | LiveBench | – | 77.5% |
| SciCode (AA) | Artificial Analysis | 55.1% | 57.4% |
| IOI | Vals AI | – | 21.8% |
| SWE-bench (Vals) | Vals AI | – | 86.6% |
| Code Migration | Vals AI | – | 29.9% |
| ProgramBench | Vals AI | – | 0.5% |
| Vibe Code Bench v1.1 | Vals AI | – | 79.1% |
| DeepSWE v1.1 | Epoch AI Benchmarking Hub | – | 54.9% |
| FrontierSWE | Epoch AI Benchmarking Hub | – | 12.0% |
| Terminal-Bench 4.0 (AA) | Artificial Analysis | 55.6% | 7.1% |
Show all 89 benchmarks
| Metric | Publisher | GPT-6.1 Terra (max) | Muse Spark 1.2 (xhigh) |
|---|---|---|---|
| Coding | |||
| Terminal-Bench 2.1 (AA) | Artificial Analysis | – | 80.2% |
| Startrise Frontend | Startrise | – | 70.3%† |
| FrontierCode 1.1 (AA) | Artificial Analysis | 36.0% | – |
| Agents & tools | |||
| APEX-Agents | Mercor | – | 45.4%† |
| Arena Agent | Arena (LMArena) | – | -7 |
| LiveBench Long Agentic | LiveBench | 48.6%† | – |
| LiveBench Browser | LiveBench | 93.1%† | – |
| LiveBench Agentic Coding | LiveBench | – | 57.6% |
| Terminal-Bench 2.1 (Vals) | Vals AI | – | 69.7% |
| τ³-Banking (AA) | Artificial Analysis | – | 34.9% |
| CyberBench | Vals AI | – | 69.5% |
| Finance Agent v2 | Vals AI | – | 60.6% |
| Harvey's Legal Agent Benchmark v1 | Vals AI | – | 25.4% |
| Legal Research Bench | Vals AI | – | 43.8% |
| SkillsBench | Vals AI | – | 53.0% |
| SREBench | Vals AI | – | 0.0% |
| Tax Agent Bench | Vals AI | – | 32.8% |
| Terminal-Bench 4.0 (Vals) | Vals AI | – | 6.1% |
| AutomationBench | Artificial Analysis | 60.2% | 40.6% |
| GDP.pdf (AA) | Artificial Analysis | 28.6% | 17.4% |
| EnterpriseOps-Gym | Artificial Analysis | – | 47.3% |
| AA-Briefcase v1.1 | Artificial Analysis | 1402 | 1327 |
| Terminal-Bench-Science 0.1 (AA) | Artificial Analysis | 57.6% | – |
| Maths | |||
| ProofBench | Vals AI | – | 43.0%† |
| LiveBench Mathematics | LiveBench | – | 91.2% |
| Arena Maths | Arena (LMArena) | – | 1491 |
| Knowledge | |||
| SimpleQA Verified | Epoch AI Benchmarking Hub | – | 60.3% |
| LiveBench 2.0 Data Analysis | LiveBench | 82.3%† | – |
| LiveBench Research | LiveBench | 73.9%† | – |
| LiveBench 1.0 Data Analysis | LiveBench | – | 76.5% |
| AA-Omniscience | Artificial Analysis | 29.8 | 27.2 |
| MMLU-Pro | Vals AI | – | 88.3% |
| LegalBench | Vals AI | – | 85.3% |
| CorpFin | Vals AI | – | 70.9% |
| TaxEval | Vals AI | – | 80.4% |
| BioMysteryBench | Vals AI | – | 64.8% |
| Excel Modeling Benchmark | Vals AI | – | 57.0% |
| MedCode | Vals AI | – | 49.4% |
| MedScribe | Vals AI | – | 90.1% |
| Public Benefits Bench v1.1 | Vals AI | – | 68.5% |
| GDP.pdf | Epoch AI Benchmarking Hub | – | 16.0% |
| AA-Omniscience: accuracy | Artificial Analysis | 49.1% | 45.4% |
| AA-Omniscience: non-hallucination | Artificial Analysis | 62.0% | 66.7% |
| Instruction following | |||
| LiveBench Language | LiveBench | – | 78.6% |
| LiveBench Instruction Following | LiveBench | – | 74.3% |
| Arena Instruction Following | Arena (LMArena) | – | 1472 |
| Human preference | |||
| Arena Text | Arena (LMArena) | – | 1491 |
| Arena Creative Writing | Arena (LMArena) | – | 1439 |
| Arena Multi-turn | Arena (LMArena) | – | 1511 |
| Arena Longer Queries | Arena (LMArena) | – | 1488 |
| Multimodal | |||
| Arena Vision | Arena (LMArena) | – | 1304 |
| LiveBench Design | LiveBench | 82.3%† | – |
| MMMU-Pro | Artificial Analysis | 84.7% | – |
| MMMU-Pro (Vals) | Vals AI | – | 86.1% |
| MortgageTax | Vals AI | – | 65.4% |
| SAGE | Vals AI | – | 47.7% |
| Long context | |||
| AA-LCR | Artificial Analysis | 82.7% | 79.0% |
| MLCR | Artificial Analysis | – | 7.2% |
| Composite | |||
| Epoch Capabilities Index | Epoch AI Benchmarking Hub | – | 155.1† |
| LiveBench 2.0 | LiveBench | 77.2%† | – |
| LiveBench 1.0 | LiveBench | – | 78.0% |
| AA Intelligence Index v4.3.2 | Artificial Analysis | 48.1 | 39.6 |
| Vals Multimodal Index | Vals AI | – | 69.8%† |
| Safety & honesty | |||
| FORTRESS | Scale AI SEAL | 18.2%† | – |
Data as of 2026-10-27. Best configuration of each model; every score links to its source on the model pages.
What changed
- Muse Spark 1.2 (xhigh): cost per task moved from $0.97/M to $1.29/M (32% up).
- Muse Spark 1.2 (xhigh): 1 new result (AA-Briefcase v1.1).
- Muse Spark 1.2 (xhigh): 1 new result (Harvey's Legal Agent Benchmark v1).
- Muse Spark 1.2 (xhigh): 2 score revisions.
- Muse Spark 1.2 (xhigh): BenchLeader Index 62.6 → 63.3.
- Muse Spark 1.2 (xhigh): 4 new results (AutomationBench, GDP.pdf (AA), MLCR…).
- Muse Spark 1.2 (xhigh): 3 new results (Chess Puzzles, ProgramBench, SREBench); 1 score revision.
- Muse Spark 1.2 (xhigh): 3 score revisions.
- Muse Spark 1.2 (xhigh): 1 score revision.
- Muse Spark 1.2 (xhigh): 3 score revisions.
Related comparisons
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- GPT-6.1 Terra vs GPT-6 Astra
- Muse Spark 1.2 vs Claude Opus 5.5
- Muse Spark 1.2 vs Claude Fable 5.1
- Muse Spark 1.2 vs GPT-6 Astra
- Muse Spark 1.2 vs Muse Wonder Full
- GPT-6.1 Sol vs Muse Spark 1.2
Rankings: Best LLM overall · Best LLM for agents · Best cheap LLMs
GPT-6.1 Terra vs Muse Spark 1.2: questions
- Is GPT-6.1 Terra better than Muse Spark 1.2?
- GPT-6.1 Terra (max) and Muse Spark 1.2 (xhigh) are neck and neck on quality (65.9 vs 63.1, within the ±8.4 margin). The BenchLeader Index combines every independent quality benchmark; the two are within the margin of error as of 2026-10-27, so check the category scores for your use.
- Which is cheaper, GPT-6.1 Terra or Muse Spark 1.2, and will that change?
- They cost the same: $2.00 per million tokens blended. No price change has been announced for either.
- Which is better for long documents?
- GPT-6.1 Terra scores higher on long-context benchmarks (66 vs 64). Both take about 1.1M tokens: GPT-6.1 Terra 1,050,000, Muse Spark 1.2 1,048,576.
- Which has lower latency?
- Muse Spark 1.2 (xhigh) answers first: 18.6 s against 131.8 s to the first answer token, as Artificial Analysis measures it. Reasoning effort drives most of this: a higher setting thinks longer before it answers.
- Which is faster, GPT-6.1 Terra or Muse Spark 1.2?
- Muse Spark 1.2 streams faster: 293 against 91 output tokens per second.
- Do independent benchmarks agree on GPT-6.1 Terra vs Muse Spark 1.2?
- Across the 11 benchmarks both have, GPT-6.1 Terra leads 9, Muse Spark 1.2 leads 2. Every overall index that rates both puts GPT-6.1 Terra ahead.
- When was GPT-6.1 Terra released?
- GPT-6.1 Terra was released on 26 Oct 2026.