BenchLeader

GPT-5.6 Sol vs GPT-6.1 Terra

Full profiles: GPT-5.6 Sol (OpenAI) and GPT-6.1 Terra (OpenAI): every benchmark, price and rank.

Updated · Data from 9 sources

As of 27 Oct 2026, GPT-5.6 Sol (max) and GPT-6.1 Terra (max) are neck and neck on quality (67.8 vs 65.9 on the BenchLeader Index, inside the ±7.9 margin of error), and GPT-6.1 Terra (max) costs 4.0× less, which makes it the better buy for most workloads. GPT-6.1 Terra leads in every category we measure both in.

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 casePickWhyConfidence
ReasoningGPT-6.1 Terra86 vs 72 category score; CritPt 28.0% vs 32.3%High
KnowledgeGPT-6.1 Terra75 vs 65 category score; AA-Omniscience 29.8 vs 22.0High
Long documentsEither67 vs 66 category score; AA-LCR 84.0% vs 82.7%Either
Images and other mediaGPT-6.1 Terra68 vs 66 category score; MMMU-Pro 84.7% vs 83.4%Medium
Lowest costGPT-6.1 Terra$2.00 vs $8.00 per 1M blended; agentic coding session $0.080 vs $0.320–
Fastest first answerEither107.7 s (GPT-5.6 Sol (max)) vs 131.8 s (GPT-6.1 Terra (max)) to the first answer token–
High volume on a budgetNeither flagshipA smaller model is usually the better fit: Cheapest good LLMs, Fastest LLMs–

Key differences

  • GPT-5.6 Sol (max) and GPT-6.1 Terra (max) are neck and neck on quality (67.8 vs 65.9, within the ±7.9 margin).
  • GPT-5.6 Sol (max) is stronger in agents & tools, coding, instruction following, long context, maths.
  • GPT-6.1 Terra (max) is stronger in composite, knowledge, multimodal, reasoning.
  • GPT-6.1 Terra (max) is 4.0× cheaper ($2.00 vs $8.00 per 1M blended).

At a glance

SpecGPT-5.6 SolGPT-6.1 Terra
DeveloperOpenAIOpenAI
Released9 Jul 202626 Oct 2026
Context window (tokens)1,050,0001,050,000
Compared atGPT-5.6 Sol (max)GPT-6.1 Terra (max)
Open weightsNoNo
Price in / out / cached input per 1M$4.00 / $20.00 / $0.400$1.00 / $5.00 / $0.050

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.

CategoryGPT-5.6 Sol (max)GPT-6.1 Terra (max)Leader
Reasoning72.286.2GPT-6.1 Terra
Coding65.9–not comparable
Agents & tools66.5–not comparable
Maths71.0–not comparable
Knowledge65.274.5GPT-6.1 Terra
Instruction following71.1–not comparable
Multimodal66.267.5GPT-6.1 Terra
Long context67.066.3level
Composite81.582.8GPT-6.1 Terra

Where sources disagree

Across the 13 benchmarks both have, GPT-5.6 Sol leads 6, GPT-6.1 Terra leads 7. Every overall index that rates both puts GPT-6.1 Terra ahead.

Overall indexGPT-5.6 Sol (max)GPT-6.1 Terra (max)Leader
BenchLeader Index67.865.9neck and neck
AA Intelligence Index v4.3.247.048.1GPT-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.

MeasureGPT-5.6 Sol (max)GPT-6.1 Terra (max)
Blended price per 1M tokens$8.00$2.00
Input / output per 1M$4.00 / $20.00$1.00 / $5.00
Cached input per 1M$0.400$0.050
Price per task: chat reply$0.0076$0.0019
Price per task: summarize a 30-page report$0.060$0.015
Price per task: code edit$0.054$0.013
Price per task: agentic coding session$0.320$0.080
Price per task: structured extraction$0.012$0.0030
Cost to run a full benchmark suite$1.99$0.403
Output speed81 tok/s91 tok/s
Time to first answer107.7 s131.8 s
Time to a complete answer113.9 s137.3 s

Per token is not per task: on Artificial Analysis' full suite GPT-5.6 Sol (max) cost $1.99 and GPT-6.1 Terra (max) $0.403, because GPT-5.6 Sol (max) used about 1.2× as many tokens for the same work.

Each model is compared at its best-ranked reasoning-effort setting. GPT-5.6 Sol (max) scores 67.8 and takes 108 s to its first answer token; GPT-5.6 Sol (xhigh) scores 66.5 in 56 s, GPT-5.6 Sol (high) scores 66.1 in 10 s. 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. 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

140 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.

MetricPublisherGPT-5.6 Sol (max)GPT-6.1 Terra (max)
BenchLeader IndexBenchLeader67.865.9
Agents & tools scoreBenchLeader66.5–
Coding scoreBenchLeader65.9–
Composite scoreBenchLeader81.582.8
Instruction following scoreBenchLeader71.1–
Knowledge scoreBenchLeader65.274.5
Long context scoreBenchLeader67.066.3
Maths scoreBenchLeader71.0–
Multimodal scoreBenchLeader66.267.5
Reasoning scoreBenchLeader72.286.2
Blended price $/MBenchLeader$8.00$2.00
Output speedBenchLeader81 tok/s91 tok/s
Time to first answerBenchLeader107.7 s131.8 s
Context windowBenchLeader1,050,000 tokens1,050,000 tokens
Reasoning
GPQA DiamondEpoch AI Benchmarking Hub93.5%–
SimpleBenchSimpleBench64.8%†–
Arena Hard PromptsArena (LMArena)1512†–
LiveBench 2.0 ReasoningLiveBench–88.7%†
LiveBench 1.0 ReasoningLiveBench91.7%–
GPQA Diamond (AA)Artificial Analysis94.1%–
Humanity's Last Exam (AA)Artificial Analysis49.5%46.3%
GPQA Diamond (Vals)Vals AI95.2%–
EnigmaEvalScale AI SEAL37.1%†–
Kagi LLM BenchmarkKagi LLM Benchmark67.0%†–
ARC-AGI-1ARC Prize96.5%–
ARC-AGI-2ARC Prize92.5%–
ARC-AGI-3ARC Prize7.8%–
CritPtArtificial Analysis32.3%28.0%
MysteryMechanismVals AI33.3%–
Chess PuzzlesEpoch AI Benchmarking Hub59.0%–
Mystery Game PuzzlesEpoch AI Benchmarking Hub58.0%–
LMCAEpoch AI Benchmarking Hub58.4%–
DTBenchEpoch AI Benchmarking Hub95.5%–
ForecastBenchForecastBench65.5%–
BTF-3Epoch AI Benchmarking Hub13.7%–
Coding
SciCodeSciCode57.1%–
WeirdMLWeirdML87.0%–
FrontierCodeCognition47.5%†–
GSO-BenchGSO-Bench76.5%†–
Show all 140 benchmarks
MetricPublisherGPT-5.6 Sol (max)GPT-6.1 Terra (max)
Coding
Arena CodingArena (LMArena)1534†–
Arena WebDevArena (LMArena)1615†–
LiveBench 2.0 CodingLiveBench–90.8%†
LiveBench 1.0 CodingLiveBench83.9%–
SciCode (AA)Artificial Analysis57.1%55.1%
LiveCodeBenchVals AI82.6%–
IOIVals AI91.2%–
SWE-bench (Vals)Vals AI96.2%–
Code MigrationVals AI52.9%–
ProgramBenchVals AI1.5%–
Vibe Code Bench 1-100Vals AI20.0%–
Vibe Code Bench v1.1Vals AI80.5%–
SWE Atlas: Codebase QnAScale AI SEAL46.0%†–
SWE Atlas: Test WritingScale AI SEAL45.9%†–
MirrorCodeEpoch AI Benchmarking Hub20.0%†–
Surface Evolver BenchEpoch AI Benchmarking Hub93.1%†–
DeepSWE v1.1Epoch AI Benchmarking Hub72.7%–
CursorBenchCursor41.7%–
ALE-BenchEpoch AI Benchmarking Hub2176.9–
FrontierSWEEpoch AI Benchmarking Hub32.2%–
Terminal-Bench 4.0 (AA)Artificial Analysis39.9%55.6%
Terminal-Bench 2.1 (AA)Artificial Analysis88.0%–
Startrise FrontendStartrise66.2%†–
FrontierCode 1.1 (AA)Artificial Analysis–36.0%
Agents & tools
Terminal-BenchTerminal-Bench37.3%–
OSWorld-Verified 2.0OSWorld27.3%–
Arena AgentArena (LMArena)6.1†–
LiveBench Long AgenticLiveBench–48.6%†
LiveBench BrowserLiveBench–93.1%†
LiveBench Agentic CodingLiveBench56.2%–
Terminal-Bench HardArtificial Analysis65.9%–
τ²-Bench Telecom (AA)Artificial Analysis85.1%–
Terminal-Bench 2.1 (Vals)Vals AI85.8%–
HiL-BenchScale AI SEAL32.3%†–
τ³-bench Bankingτ²-bench46.9%†–
τ³-Banking (AA)Artificial Analysis44.3%–
ITBench SRE (AA)Artificial Analysis56.2%–
Analyst Agent (AA)Artificial Analysis47.5%–
CUA-benchVals AI8.3%–
CyberBenchVals AI76.3%–
Finance Agent v2Vals AI53.8%–
Harvey's Legal Agent Benchmark v1Vals AI2.5%–
Legal Research BenchVals AI48.1%–
SkillsBenchVals AI54.1%–
SREBenchVals AI30.5%–
Tax Agent BenchVals AI31.1%–
Terminal-Bench 4.0 (Vals)Vals AI37.9%–
Terminal-Bench ScienceVals AI20.0%–
Time Horizon Index: KSPVals AI23.8%–
Web Search IndexVals AI43.6%–
Arena SearchArena (LMArena)1258†–
BALROGBALROG60.0%–
PostTrainBenchEpoch AI Benchmarking Hub36.2%–
GBAEvalEpoch AI Benchmarking Hub52.6%†–
Vending-Bench 2Andon Labs9619.4†–
AutomationBenchArtificial Analysis60.1%60.2%
GDP.pdf (AA)Artificial Analysis27.2%28.6%
EnterpriseOps-GymArtificial Analysis42.9%–
AA-Briefcase v1.1Artificial Analysis14791402
Terminal-Bench-Science 0.1 (AA)Artificial Analysis22.4%57.6%
FACTS SearchGoogle88.5%†–
Maths
FrontierMath Tiers 1–3Epoch AI Benchmarking Hub89.1%–
FrontierMath Tier 4Epoch AI Benchmarking Hub82.9%–
OTIS Mock AIMEEpoch AI Benchmarking Hub100.0%–
ProofBenchVals AI83.0%–
LiveBench MathematicsLiveBench96.2%–
Arena MathsArena (LMArena)1496†–
Knowledge
SimpleQA VerifiedEpoch AI Benchmarking Hub69.7%–
LiveBench 2.0 Data AnalysisLiveBench–82.3%†
LiveBench ResearchLiveBench–73.9%†
LiveBench 1.0 Data AnalysisLiveBench79.8%–
AA-OmniscienceArtificial Analysis22.029.8
MMLU-ProVals AI89.1%–
LegalBenchVals AI87.0%–
CorpFinVals AI64.4%–
TaxEvalVals AI74.8%–
PRBench FinanceScale AI SEAL50.5%–
PRBench LegalScale AI SEAL50.5%–
BioMysteryBenchVals AI71.1%–
Excel Modeling BenchmarkVals AI72.3%–
MedCodeVals AI44.0%–
MedScribeVals AI85.2%–
Public Benefits Bench v1.1Vals AI66.5%–
DrugDiscoveryBenchScale AI SEAL56.5%–
EBR-benchEpoch AI Benchmarking Hub44.8%–
GDP.pdfEpoch AI Benchmarking Hub30.7%–
AA-Omniscience: accuracyArtificial Analysis59.4%49.1%
AA-Omniscience: non-hallucinationArtificial Analysis7.8%62.0%
Instruction following
LiveBench LanguageLiveBench87.7%–
LiveBench Instruction FollowingLiveBench71.8%–
IFBenchArtificial Analysis72.7%–
Arena Instruction FollowingArena (LMArena)1491†–
Human preference
Arena TextArena (LMArena)1485†–
EQ-Bench 4EQ-Bench1240†–
Arena Creative WritingArena (LMArena)1470†–
Arena Multi-turnArena (LMArena)1490†–
Arena Longer QueriesArena (LMArena)1499†–
Multimodal
Arena VisionArena (LMArena)1281†–
LiveBench DesignLiveBench–82.3%†
MMMU-ProArtificial Analysis83.4%84.7%
MMMU-Pro (Vals)Vals AI88.8%–
MortgageTaxVals AI67.3%–
SAGEVals AI52.6%–
Blueprint-Bench 2Epoch AI Benchmarking Hub33.6%†–
Long context
AA-LCRArtificial Analysis84.0%82.7%
Arena DocumentArena (LMArena)1489†–
MLCRArtificial Analysis30.0%–
Composite
Epoch Capabilities IndexEpoch AI Benchmarking Hub162.8†–
LiveBench 2.0LiveBench–77.2%†
LiveBench 1.0LiveBench81.0%–
AA Intelligence Index v4.3.2Artificial Analysis47.048.1
Vals RSI IndexVals AI23.9%–
Vals Science IndexVals AI41.5%–
Vals Multimodal IndexVals AI72.6%–
Safety & honesty
FORTRESSScale AI SEAL20.1%†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

  • GPT-5.6 Sol (max): 1 new result (AA-Briefcase v1.1).
  • GPT-5.6 Sol (max): 3 new results (Harvey's Legal Agent Benchmark v1, Vals RSI Index, Vals Science Index).
  • GPT-5.6 Sol (max): 1 score revision.
  • GPT-5.6 Sol (max): 1 new result (ForecastBench).
  • GPT-5.6 Sol (max): 5 new results (AutomationBench, GDP.pdf (AA), MLCR…).
  • GPT-5.6 Sol (max): 1 score revision.
  • GPT-5.6 Sol (max): 1 score revision.
  • GPT-5.6 Sol (max): 1 new result (PRBench Legal).
  • GPT-5.6 Sol (max): 1 new result (DrugDiscoveryBench).
  • GPT-5.6 Sol (max): 1 new result (PRBench Legal).

Rankings: Best LLM overall · Best LLM for agents · Best cheap LLMs

GPT-5.6 Sol vs GPT-6.1 Terra: questions

Is GPT-5.6 Sol better than GPT-6.1 Terra?
GPT-5.6 Sol (max) and GPT-6.1 Terra (max) are neck and neck on quality (67.8 vs 65.9, within the ±7.9 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-5.6 Sol or GPT-6.1 Terra, and will that change?
GPT-6.1 Terra is cheaper today: $2.00 against $8.00 per million tokens, blended at three input tokens per output token. No price change has been announced for either.
Which is better for long documents?
They are level on long-context benchmarks (67 vs 66). Both accept 1,050,000 tokens of context.
Which has lower latency?
GPT-5.6 Sol (max) answers first: 107.7 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-5.6 Sol or GPT-6.1 Terra?
GPT-6.1 Terra streams faster: 91 against 81 output tokens per second.
Do independent benchmarks agree on GPT-5.6 Sol vs GPT-6.1 Terra?
Across the 13 benchmarks both have, GPT-5.6 Sol leads 6, GPT-6.1 Terra leads 7. 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.