Claude Opus 4.6 vs GPT-5.6 Terra
At a Glance
| Compare | Claude Opus 4.6Anthropic |  GPT-5.6 TerraOpenAI |
|---|---|---|
| Intelligence, Cost, and Efficiency | ||
| IntelligenceHigher is better · MM Intelligence v2.5 | #12 of 4676.2 score · 3/3 sources · complete | #13 of 4674.9 score · 3/3 sources · complete |
| CostLower is better · Published-token output estimate | #33 of 44$0.241 per LiveBench case | #35 of 44$0.266 per LiveBench case |
| EfficiencyHigher is better · MM Efficiency v1.5 | #19 of 3853.2 score · 3/3 sources · complete | #23 of 3851.5 score · 3/3 sources · complete |
| Pricing and Limits | ||
| Input priceFrom · USD / 1M tokens | $5.00Anthropic ↗ · Sep 3, 2026 | $2.00Openai ↗ · Sep 3, 2026 |
| Output priceFrom · USD / 1M tokens | $25.00Anthropic ↗ · Sep 3, 2026 | $12.00Openai ↗ · Sep 3, 2026 |
| Context windowMaximum documented tokens | 1,000K | 1,050K |
| Model facts checked | Sep 3, 2026View model evidence → | Aug 28, 2026View model evidence → |
Token prices are the lowest available sourced USD rates; input and output may use different providers. Cost ranking estimates output spend on LiveBench, not a full request bill. Ranking methodology →
Available Benchmarks
| Benchmark | Claude Opus 4.6 | GPT-5.6 Terra |
|---|---|---|
| ARC-AGI-1verified-v1-ba05d69f6453 · verified_score · leader | 94.0097% of row best · percent · Claude Opus 4.6 (120K, High) | 96.50100% of row best · percent · GPT-5.6 Terra (Max) |
| ARC-AGI-2verified-v2-6c676fa3e9af · verified_score · leader | 69.1782% of row best · percent · Claude Opus 4.6 (120K, High) | 83.90100% of row best · percent · GPT-5.6 Terra (Max) |
| LMArena Document Arenadocument-2026-09-13-d25aabda0010 · arena_rating · leader | 1,507.05100% of row best · rating · claude-opus-4-6; 95% CI [1501.18336037, 1512.92390326]; votes 41260; rank 4 | 1,471.5898% of row best · rating · gpt-5.6-terra-xhigh; 95% CI [1463.31179298, 1479.85049651]; votes 5787; rank 13 |
| LMArena Text Arenatext-2026-09-13-d25aabda0010 · arena_rating · leader | 1,497.54100% of row best · rating · claude-opus-4-6; 95% CI [1494.14263199, 1500.94441396]; votes 75878; rank 5 | 1,446.2297% of row best · rating · gpt-5.6-terra-xhigh; 95% CI [1441.41414497, 1451.02563541]; votes 28119; rank 52 |
| LMArena Vision Arenavision-2026-09-13-d25aabda0010 · arena_rating · leader | 1,311.54100% of row best · rating · claude-opus-4-6; 95% CI [1305.06259741, 1318.02420613]; votes 25140; rank 9 | 1,269.9097% of row best · rating · gpt-5.6-terra-xhigh; 95% CI [1261.54272100, 1278.25950723]; votes 7726; rank 36 |
| LiveBench2026-06-25 · overall · leader | 78.6996% of row best · percent · claude-opus-4-6-thinking-auto-high-effort · 9,651 output tokens / case | 82.31100% of row best · percent · gpt-5.6-terra-max · 22,145 output tokens / case |
| ToneBench2026-09-11-10-task-4ef099199c9c · overall_score · unverified | 84.2197% of row best · points · Claude Opus 4.6 · 13,556 output tokens / case | 86.39100% of row best · points · GPT-5.6 Terra (ultra) · 11,336 output tokens / case |
| Overall ResultCounted from the protocol-matched rows above | 3 benchmark winsNo overall winner | 3 benchmark winsNo overall winner |
Third-party benchmark Only like-for-like primary-publisher results are shown; raw scores, relative scores, configuration, and token spend remain visible.
Side-by-Side Facts
| Field | Claude Opus 4.6 | GPT-5.6 Terra |
|---|---|---|
| Developer | Anthropic | OpenAI |
| Family | Claude 4 | Gpt 5 6 |
| Model | Claude Opus 4.6 | GPT-5.6 Terra |
| Version | Claude Opus 4.6 | GPT-5.6 Terra |
| Lifecycle | active | active |
| Released | 2026-02-05 | Unknown |
| Knowledge cutoff | 2025-05-01 | 2026-02-16 |
| Input modalities | Text, Image | Text, Image |
| Output modalities | Text | Text |
| Context window | 1,000K | 1,050K |
| Total parameters | Unknown | Unknown |
| Active parameters | Unknown | Unknown |
| License | Unknown | Unknown |
| Open weights | No | No |
| API available | Yes | Yes |
| Self-hostable | No | No |
| Provider access | Anthropic (Standard) | Openai (Standard), Openrouter (Standard) |
| Capabilities | chat, generation, reasoning, structured_outputs, tools | chat, generation, reasoning, tools |
Claude Opus 4.6 Capabilities
GPT-5.6 Terra Capabilities
Related Comparisons
All image comparisons →| A | Pair | B | Context |
|---|---|---|---|
Claude Opus 4.6Anthropic | vs | GPT-6 AstraOpenAI | cross-developer peersimage, text |
Claude Fable 5.1Anthropic | vs | Claude Opus 4.6Anthropic | family variantsimage, text |
Claude Opus 4.6Anthropic | vs |  Gemini 3.1 ProGoogle DeepMind | cross-developer peerstext |
Claude Opus 4.6Anthropic | vs |  DeepSeek-V4.1-FlashDeepSeek | cross-developer peersimage, text |
Claude Opus 4.6Anthropic | vs | Grok 4.6xAI | cross-developer peersimage, text |
Claude Opus 4.6Anthropic | vs |  Qwen3.8-MaxQwen | cross-developer peersimage, text |
Claude Opus 4.6Anthropic | vs |  Kimi-K3Moonshot AI | cross-developer peersimage, text |
 MiniMax-M3MiniMax | vs | Claude Opus 4.6Anthropic | cross-developer peersimage, text |
Claude Opus 4.6Anthropic | vs |  GLM-5.3Z.ai | cross-developer peerstext |
Claude Opus 4.6Anthropic | vs |  Hy4 previewTencent | cross-developer peerstext |
Claude Opus 4.6Anthropic | vs | Seed 2.1 ProByteDance Seed | cross-developer peersimage, text |
Claude Opus 4.6Anthropic | vs |  Mistral Large 3Mistral AI | cross-developer peersimage, text |
Primary Evidence
Sources and Freshness
Questions
Claude Opus 4.6 vs GPT-5.6 Terra FAQs
Is Claude Opus 4.6 or GPT-5.6 Terra better for coding?+
This comparison does not currently contain a protocol-matched coding benchmark for both Claude Opus 4.6 and GPT-5.6 Terra, so Model Markets cannot name a coding leader from pricing, context size, or capability labels alone.
Which is cheaper, Claude Opus 4.6 or GPT-5.6 Terra?+
Claude Opus 4.6 is $5.00 and GPT-5.6 Terra is $2.00 per million tokens, so GPT-5.6 Terra is cheaper on this metric. Claude Opus 4.6 is $25.00 and GPT-5.6 Terra is $12.00 per million tokens, so GPT-5.6 Terra is cheaper on this metric.
Which has a larger context window, Claude Opus 4.6 or GPT-5.6 Terra?+
GPT-5.6 Terra has the larger sourced context window. Claude Opus 4.6 supports 1,000K and GPT-5.6 Terra supports 1,050K.
Which performs better in benchmarks, Claude Opus 4.6 or GPT-5.6 Terra?+
There is no overall benchmark winner: The verified common benchmarks do not produce a majority winner.
Can Claude Opus 4.6 or GPT-5.6 Terra be self-hosted?+
Both models have the same recorded self-hosting status: unsupported. Claude Opus 4.6 is not marked open weight; GPT-5.6 Terra is not marked open weight.
Can Claude Opus 4.6 and GPT-5.6 Terra understand images?+
Claude Opus 4.6 is documented with image input; GPT-5.6 Terra is documented with image input. This reflects supported input modalities, not vision quality.
Which can generate longer answers, Claude Opus 4.6 or GPT-5.6 Terra?+
Neither has a larger sourced maximum output. Claude Opus 4.6 is 128K and GPT-5.6 Terra is 128K.
Do Claude Opus 4.6 and GPT-5.6 Terra support reasoning and tool use?+
Claude Opus 4.6: reasoning, tool calling, and image input. GPT-5.6 Terra: reasoning, tool calling, and image input. Feature support does not establish relative quality.
Which is available from more inference providers, Claude Opus 4.6 or GPT-5.6 Terra?+
Claude Opus 4.6 has 1 sourced provider route; GPT-5.6 Terra has 2, so GPT-5.6 Terra has broader tracked availability.
Which offers better value, Claude Opus 4.6 or GPT-5.6 Terra?+
There is no universal value winner. Compare the input and output prices above with the matched benchmark result for your workload: cheaper tokens can be offset by different quality, token usage, latency, or provider availability.