AI model comparison
GPT-6.1 Terra vs GPT-5.6 Terra
Side by side comparison of GPT-6.1 Terra and GPT-5.6 Terra on pricing, benchmark scores, context window, and more.
GPT-6.1 Terra is the mid-tier model in OpenAI's GPT-6.1 series, priced below GPT-6.1 Sol.
- Input / 1M
- $1
- Output / 1M
- $5
- Context
- 1.05M
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.
- Input / 1M
- $2
- Output / 1M
- $12
- Context
- 1.05M
Comparing image generators? Compare image models
At a glance
Quick verdict
How the two models stack up on the things people ask about most.
Lower price
GPT-6.1 Terra
2.2x cheaper for a typical chat
Higher intelligence score
Not available
Not enough benchmark data
Larger context window
Tie
1.05M vs 1.05M tokens
Newer release
GPT-6.1 Terra
Released October 26, 2026
Benchmarks
Benchmark scores
Independent scores from Artificial Analysis. Higher is better.
Intelligence index
GPT-6.1 Terra51GPT-5.6 TerraNot availableCoding index
GPT-6.1 TerraNot availableGPT-5.6 Terra76.7Agentic index
GPT-6.1 TerraNot availableGPT-5.6 Terra43.2Pricing
GPT-6.1 Terra vs GPT-5.6 Terra API pricing
Per-token API rates. Cheaper option highlighted.
| Metric | GPT-6.1 Terra | GPT-5.6 Terra |
|---|---|---|
| Input tokensPer 1M tokens | $1 | $2 |
| Output tokensPer 1M tokens | $5 | $12 |
| Cached input (read)Per 1M tokens | $0.05 | $0.20 |
| Cache writePer 1M tokens | $1.25 | $2.50 |
| Long-context pricingPer 1M tokens, for very long prompts | $2 in / $7.50 out above 272K | $4 in / $18 out above 272K |
| Web searchPer request | $0.01 | $0.01 |
What it costs in practice
Estimated cost per 1,000 requests at standard rates. Coding and long-document figures also show the cost when the input is already cached.
Chat message
2K in, 500 out
GPT-6.1 Terra$4.50GPT-5.6 Terra$10Coding task
30K in, 4K out
GPT-6.1 Terra$50$21.50 cachedGPT-5.6 Terra$108$54 cachedLong document summary
150K in, 2K out
GPT-6.1 Terra$160$17.50 cachedGPT-5.6 Terra$324$54 cachedSpecs
Context window and capabilities
How much each model can read, how much it can write, and what it accepts as input.
| Metric | GPT-6.1 Terra | GPT-5.6 Terra |
|---|---|---|
| Context window | 1.05M tokens | 1.05M tokens |
| Max output | 128K tokens | 128K tokens |
| Input types | File, Image, Text | File, Image, Text |
| Output types | Text | Text |
| Reasoning effort levels | Max, Extra high, High, Medium, Low, None | Max, Extra high, High, Medium, Low, None |
| Default reasoning effort | Medium | Medium |
| Release date | October 26, 2026 | July 9, 2026 |
Features
Supported features
API features available for each model.
| Metric | GPT-6.1 Terra | GPT-5.6 Terra |
|---|---|---|
| Tool calling | Supported | Supported |
| Structured outputs | Supported | Supported |
| JSON mode | Supported | Supported |
| Reasoning | Supported | Supported |
| Temperature | Not supported | Not supported |
| Stop sequences | Not supported | Not supported |
| Deterministic seed | Supported | Supported |
| Verbosity control | Supported | Supported |
Keep exploring
More on these models
Other head-to-heads, the full model page, and the alternatives list for each model.
GPT-6.1 TerraView full model details- GPT-6.1 Terra vs Claude Opus 5.5
- GPT-6.1 Terra vs GPT-6 Astra
- GPT-6.1 Terra vs GPT-6.1 Sol
- GPT-6.1 Terra vs Claude Sonnet 5.5
- GPT-6.1 Terra vs Gemini 4 Argon
- GPT-6.1 Terra vs Claude Fable 5.1
- GPT-6.1 Terra vs Kimi K3.1 Pro
- GPT-6.1 Terra vs Muse Spark 1.3
- GPT-6.1 Terra vs Claude Haiku 5.5
- GPT-6.1 Terra vs GPT-6 Luna
- GPT-6.1 Terra vs DeepSeek V4.1 Flash 1017
- GPT-6.1 Terra vs DeepSeek V4.1 Flash
- GPT-6.1 Terra vs GLM 5.3 Flash
- GPT-6.1 Terra vs Hy4 preview
- GPT-6.1 Terra vs GLM 5.2
- GPT-6.1 Terra vs GPT-6 Sol
Our take
GPT-6.1 Terra is 2.2x cheaper for a typical chat. The right pick depends on your workload, so the quickest way to settle it is to send the same prompt to both and compare.
FAQ
Frequently asked questions
Is GPT-6.1 Terra or GPT-5.6 Terra cheaper?
GPT-6.1 Terra is cheaper for a typical chat (2K input tokens and 500 output tokens). GPT-6.1 Terra costs $1 per 1M input tokens and $5 per 1M output tokens, while GPT-5.6 Terra costs $2 per 1M input tokens and $12 per 1M output tokens.
Which has a bigger context window, GPT-6.1 Terra or GPT-5.6 Terra?
GPT-6.1 Terra supports up to 1.05M tokens of context, compared with 1.05M for GPT-5.6 Terra.
Can I use GPT-6.1 Terra and GPT-5.6 Terra at the same time?
Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see GPT-6.1 Terra and GPT-5.6 Terra answer side by side and keep the better response.
Why choose? Ask both.
Send one prompt to GPT-6.1 Terra and GPT-5.6 Terra at the same time. Compare the answers side by side and keep the best one.