AI Models · Paid vs Paid

Claude Opus 5.5 Paid vs GPT-5.6 Terra Paid

Claude Opus 5.5 vs GPT-5.6 Terra compared — price per token, context window, multimodality, openness and which to choose. Full 2026 breakdown.

Prices & specs refreshed from live data · olud.ai

Open-model prices = cheapest provider via OpenRouter; official maker rates may be higher.

Claude Opus 5.5PaidAnthropic
$4 /M input
$20 /M outputManaged API (no infra to run)
TypeProprietary
Context window1M tokens
MultimodalYes
Self-hostNo
GPT-5.6 TerraPaidOpenAI
$2 /M input
$12 /M outputManaged API (no infra to run)
TypeProprietary
Context window1.1M tokens
MultimodalYes
Self-hostNo
Choose GPT-5.6 Terra for the lower output price ($12/M vs $20/M). It also gives you the larger 1.1M context window.

Claude Opus 5.5 vs GPT-5.6 Terra specs

SpecClaude Opus 5.5GPT-5.6 TerraWinner
MakerAnthropicOpenAI–
TypeProprietaryProprietary–
Context window1M tokens1.1M tokensGPT-5.6 Terra
Input price$4/M$2/MGPT-5.6 Terra
Output price$20/M$12/MGPT-5.6 Terra
Vision / multimodalYesYes= Tie
Tool / function callingYesYes= Tie
Self-hostableNo (API only)No (API only)–
LicenseProprietaryProprietary–

Price gap & when to choose each

1.7×cheaper per output token

GPT-5.6 Terra is ~1.7× cheaper than Claude Opus 5.5 on output tokens ($12 vs $20 per M tokens).

Choose Claude Opus 5.5 if…
  • You want frontier performance through a managed API
  • You value reliability & ecosystem
  • You don't want to manage infrastructure
Choose GPT-5.6 Terra if…
  • You want frontier performance through a managed API
  • You need the longer 1.1M context window
  • You want the lower output price
  • You value reliability & ecosystem
  • You don't want to manage infrastructure

Feature comparison

CapabilityClaude Opus 5.5GPT-5.6 Terra
Open weights (downloadable)✗✗
Self-hostable✗✗
Runs fully offline✗✗
Vision / multimodal✓✓
Tool / function calling✓✓
1M+ context window✓✓

Benchmarks: Claude Opus 5.5 vs GPT-5.6 Terra

Independent benchmark scores measured by Artificial Analysis. Higher is better (except latency).

Claude Opus 5.5
GPT-5.6 Terra
Intelligence index
57.6
42.1
Humanity's Last Exam
61.4%
42.9%
Long Context Reasoning
84.7%
83%
SciCode
66.9%
55%
Coding index
–
76.7
GPQA
–
92.5%
IFBench
–
71.2%
τ²-Bench
–
86.3%
τ-Bench Banking
–
40.2%
Terminal-Bench
–
88%
Terminal-Bench Hard
–
57.6%
Speed
96.6 tok/s
142.5 tok/s
Latency
466.45s
96.81s
Intelligence per $
7.2
9.4

Benchmark data by Artificial Analysis.

How Claude Opus 5.5 and GPT-5.6 Terra score

🤝 Neck and neck on these criteria (3.1 vs 3.2 / 5).
CriterionClaude Opus 5.5GPT-5.6 Terra
Cost-efficiency3.03.5
Context window5.05.0
Openness1.51.5
Self-hosting1.01.0
Multimodality5.05.0

Scores come from live data — output price (cost), context length, open vs closed weights (openness & self-hosting) and vision/tool support (multimodality). Raw task quality isn't scored here; it depends on your benchmark — see the verdict.

What each model is

Claude Opus 5.5 Paid

Anthropic · Proprietary

Claude Opus 5.5 is Anthropic's flagship model for demanding reasoning, coding, and long-horizon agentic work, succeeding Claude Opus 5. It is particularly strong at multi-step changes in large codebases, code...

GPT-5.6 Terra Paid

OpenAI · Proprietary

GPT-5.6 Terra is a balanced model in OpenAI's GPT-5.6 series, positioned between the flagship Sol tier and the cost-efficient Luna tier. It is suited for everyday coding, reasoning, and agentic...

Other models in these families

These variants are tracked but not compared here — one page per family keeps the comparison readable.

Other variants tracked
Claude Opus 5.5 (batch)Claude Opus 5Claude Opus 5 (batch)Claude Opus 4.8Claude Opus 4.8 (batch)Claude Opus 4.7Claude Opus 4.7 (batch)Claude Opus 4.6Claude Opus 4.6 (batch)Claude Opus 4.5Claude Opus 4.5 (batch)Claude Opus 4.1Claude Opus 4.1 (batch)

Frequently asked questions

Claude Opus 5.5 vs GPT-5.6 Terra — which is cheaper?

GPT-5.6 Terra is cheaper on output ($12/M vs $20/M).

Which has the larger context window?

GPT-5.6 Terra offers the larger context window (1.1M tokens).

Claude Opus 5.5 vs GPT-5.6 Terra — which should I pick in 2026?

Choose GPT-5.6 Terra for the lower output price ($12/M vs $20/M). It also gives you the larger 1.1M context window.

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