Claude Opus 5 vs GPT-5.6 Terra
Anthropic vs OpenAI · Prices checked 12 August 2026
GPT-5.6 Terra is the cheaper of the two by a wide margin: $5.00 per million tokens blended against $11.00, roughly 2.2× less. A single 100K-input, 10K-output job costs $0.320 on GPT-5.6 Terra against $0.750 on Claude Opus 5.
GPT-5.6 Terra takes a 1,050,000-token context window against 1,000,000, giving a modest edge for long documents or whole-codebase work. Claude Opus 5 was released Jul 2026; GPT-5.6 Terra Jul 2026.
Pricing and capacity
| Metric | Claude Opus 5 | GPT-5.6 Terra | Difference |
|---|---|---|---|
| Input / 1M tokens | $5.00 | $2.00 | 2.5× |
| Output / 1M tokens | $25.00 | $12.00 | 2.1× |
| Blended · 70/30calculated | $11.00 | $5.00 | 2.2× |
| Blended · 50/50calculated | $15.00 | $7.00 | 2.1× |
| Blended · 80/20calculated | $9.00 | $4.00 | 2.3× |
| Blended · 20/80calculated | $21.00 | $10.00 | 2.1× |
| Job cost · 100K + 10Kcalculated | $0.750 | $0.320 | 2.3× |
| Job cost · 1M + 100Kcalculated | $7.50 | $3.20 | 2.3× |
| Context window | 1,000,000 | 1,050,000 | 5% |
Input and output rates are as published by each provider. Blended and job-cost rows are calculated comparison metrics, not published prices — how they are derived.
Benchmarks
These two models do not currently report scores on any of the same benchmark suites, so there is no like-for-like capability comparison to show. Rather than pad the page with one-sided numbers, the benchmark leaderboards list every score we do hold.
What each model is for
Claude Opus 5
Anthropic · Frontier
Anthropic positions Opus 5 as the model to reach for by default rather than to ration: it launched at $5/$25 per MTok, half the price of the previous Opus flagship, while keeping the 1M-token context window and multimodal text, image and file input. It sits below Fable 5 in the Claude ladder and above Sonnet 5.
- Frontier capability at half the previous Opus price
- 1M-token context
- Agentic coding and tool use
- Text, image & file input
GPT-5.6 Terra
OpenAI · Balanced
The balanced everyday tier of GPT-5.6, which OpenAI describes as competitive with GPT-5.5 at a lower price. Terra is the cheaper path for scoped implementation work and first-pass review, where Sol's full reasoning budget is more than the task needs. Standard short-context pricing is $2/$12 per MTok with cached input at $0.20, roughly 60% below Sol for the same context window.
- GPT-5.5-class performance at lower cost
- Scoped implementation work
- First-pass code review
- Tool calling
Frequently asked questions
Which is cheaper, Claude Opus 5 or GPT-5.6 Terra?
GPT-5.6 Terra is the cheaper of the two by a wide margin: $5.00 per million tokens blended against $11.00, roughly 2.2× less. A single 100K-input, 10K-output job costs $0.320 on GPT-5.6 Terra against $0.750 on Claude Opus 5. Blended cost weights input at 70% and output at 30%; price your own token split for an exact answer, since the cheaper model on a blended basis is not always cheaper for your workload.
Which has the larger context window, Claude Opus 5 or GPT-5.6 Terra?
GPT-5.6 Terra takes a 1,050,000-token context window against 1,000,000, giving a modest edge for long documents or whole-codebase work. The context window caps everything in a single request: prompt, retrieved documents, conversation history and the model’s own output all share it.
Can I compare Claude Opus 5 and GPT-5.6 Terra on my own numbers?
Yes. Open both in the side-by-side comparison tool to see every field at once, or use the token calculator to price your actual prompt and monthly request volume against each model. Both are free and need no sign-up.
Price it for your own workload
Related matchups
Terms used on this page
Prices and scores are recomputed on every deploy from the catalogue. Prices checked 12 August 2026.