GPT-5.6 Terra
Newer version available: GPT-6.1 Terra
- Family
- GPT-5.6
- Released
- 2026-07-09
- Context
- 1.05M
- Max output
- 128K
- Architecture
- Decoder Only
- Specialization
- general
- Openness
- Proprietary
- License
- ProprietaryRestricted
- Weights
- Not released
- Code
- Unknown
Cheapest of 2 routes · OpenAI API · cache read $0.200
About
OpenAI's balanced mid-tier GPT-5.6 model. Terra delivers performance competitive with GPT-5.5 at about 2x lower cost, suited for high-volume production workloads such as customer support, document analysis, and internal tooling. Generally available July 9, 2026 across ChatGPT, Codex, and the OpenAI API (model ID gpt-5.6-terra). Supports text and image inputs, reasoning, tool use, prompt caching, and Batch API with a 1,050,000-token context window and 128K max output.
Providers(2)
Compare all 2Compare API pricing across 2 tracked provider routes for input and output tokens, batch, and cached reads when available.
| Provider | Input / 1M | Output / 1M | Cache | Route |
|---|---|---|---|---|
| OpenAI API | $2.00 | $12.00 | read $0.200 | Serverless |
| OpenRouter | $2.00 | $12.00 | read $0.200 | Serverless |
Available via routers & gateways(15)
LiteLLM
GatewayOpen-source Python SDK and proxy server that unifies 100+ LLM APIs behind a single OpenAI-compatible interface, with load balancing, cost tracking, and configurable failover.
OpenRouter
HybridUnified hybrid gateway to 500+ models from 80+ providers via a single OpenAI-compatible API, with an optional Auto Router that selects a model per prompt from market spend data.
Portkey
GatewayProduction AI gateway routing to 1,600+ LLMs with failover, load balancing, caching, and guardrails; MIT-licensed open-source core is self-hostable. Now part of Palo Alto Networks as Prisma AIRS AI Gateway.
AIRouter
RouterCommercial LLM router (branded "AI Router" on its site) that picks the best model per request via a Decision API or an OpenAI-compatible Chat Completions endpoint, with a private selection mode that routes on anonymized patterns; sold as BYOK subscription plans priced by routed tokens.
Helicone
GatewayObservability-first AI gateway with routing, caching, rate limiting, and request tracing; Apache-2.0 open-source platform with a managed hosted tier for logging and analytics.
Kong AI Gateway
GatewayMulti-LLM AI gateway built on Kong Gateway 3.x, adding semantic routing, load balancing, guardrails, and MCP traffic analytics as plugins over Kong's existing API management platform.
Capabilities
Benchmark peer barsfor RAG
No task-mapped benchmark peers are available for this model yet.
Benchmark scores(19)
| Benchmark | Score | Version | Evaluation | Source |
|---|---|---|---|---|
| 57.7 | length-adjusted; raw 62.4; mean response 3618 charsObserved 2026-06-26 | — | ||
| 57.0 | length-adjusted; raw 58.7; mean response 2285 charsObserved 2026-06-26 | — | ||
| 32.7 | length-adjusted; raw 34.3; mean response 2199 charsObserved 2026-06-26 | — | ||
| 95.1 | length-adjusted; raw 95.2; mean response 2247 charsObserved 2026-06-26 | — | ||
| 28.5 | GPT Pro (Extended); max reasoning comparatorObserved 2026-06-30 | — | ||
| 64.9 | CursorBench 3.2Observed 2026-07-18 | Configuration: GPT-5.6 Terra Max Harness: CursorBench 3.2 productized Cursor-agent workflow Evaluator: Cursor Confidence: confirmed Cost/task: $2.89 Tokens/task: 32,969 Steps/task: 47 Notes: Cursor vendor-reported result; not independently reproducible. Results are subject to variance, and small score differences may not be statistically meaningful. | ||
| 59.2 | CursorBench 3.2Observed 2026-07-18 | Configuration: GPT-5.6 Terra Extra High Harness: CursorBench 3.2 productized Cursor-agent workflow Evaluator: Cursor Confidence: confirmed Cost/task: $1.44 Tokens/task: 16,089 Steps/task: 29 Notes: Cursor vendor-reported result; not independently reproducible. Results are subject to variance, and small score differences may not be statistically meaningful. | ||
| 54.2 | CursorBench 3.2Observed 2026-07-18 | Configuration: GPT-5.6 Terra High Harness: CursorBench 3.2 productized Cursor-agent workflow Evaluator: Cursor Confidence: confirmed Cost/task: $0.89 Tokens/task: 9,468 Steps/task: 23 Notes: Cursor vendor-reported result; not independently reproducible. Results are subject to variance, and small score differences may not be statistically meaningful. | ||
| 50.3 | CursorBench 3.2Observed 2026-07-18 | Configuration: GPT-5.6 Terra Medium Harness: CursorBench 3.2 productized Cursor-agent workflow Evaluator: Cursor Confidence: confirmed Cost/task: $0.61 Tokens/task: 6,222 Steps/task: 20 Notes: Cursor vendor-reported result; not independently reproducible. Results are subject to variance, and small score differences may not be statistically meaningful. | ||
| 46.9 | CursorBench 3.2Observed 2026-07-18 | Configuration: GPT-5.6 Terra Low Harness: CursorBench 3.2 productized Cursor-agent workflow Evaluator: Cursor Confidence: confirmed Cost/task: $0.53 Tokens/task: 5,312 Steps/task: 19 Notes: Cursor vendor-reported result; not independently reproducible. Results are subject to variance, and small score differences may not be statistically meaningful. | ||
| 41.3 | CursorBench 4.0Observed 2026-09-10 | Configuration: GPT-5.6 Terra Max Harness: CursorBench 4.0 productized Cursor-agent workflow Evaluator: Cursor Confidence: confirmed Cost/task: $5.14 Tokens/task: 60,814 Steps/task: 107 Notes: Cursor vendor-reported configuration result; not independently reproducible. Results are subject to variance, and small score differences may not be statistically meaningful. | ||
| 33.6 | CursorBench 4.0Observed 2026-09-10 | Configuration: GPT-5.6 Terra Extra High Harness: CursorBench 4.0 productized Cursor-agent workflow Evaluator: Cursor Confidence: confirmed Cost/task: $1.81 Tokens/task: 23,436 Steps/task: 43 Notes: Cursor vendor-reported configuration result; not independently reproducible. Results are subject to variance, and small score differences may not be statistically meaningful. | ||
| 30.7 | CursorBench 4.0Observed 2026-09-10 | Configuration: GPT-5.6 Terra High Harness: CursorBench 4.0 productized Cursor-agent workflow Evaluator: Cursor Confidence: confirmed Cost/task: $1.11 Tokens/task: 13,162 Steps/task: 33 Notes: Cursor vendor-reported configuration result; not independently reproducible. Results are subject to variance, and small score differences may not be statistically meaningful. | ||
| 27.6 | CursorBench 4.0Observed 2026-09-10 | Configuration: GPT-5.6 Terra Medium Harness: CursorBench 4.0 productized Cursor-agent workflow Evaluator: Cursor Confidence: confirmed Cost/task: $0.64 Tokens/task: 7,307 Steps/task: 25 Notes: Cursor vendor-reported configuration result; not independently reproducible. Results are subject to variance, and small score differences may not be statistically meaningful. | ||
| 25.2 | CursorBench 4.0Observed 2026-09-10 | Configuration: GPT-5.6 Terra Low Harness: CursorBench 4.0 productized Cursor-agent workflow Evaluator: Cursor Confidence: confirmed Cost/task: $0.52 Tokens/task: 5,914 Steps/task: 23 Notes: Cursor vendor-reported configuration result; not independently reproducible. Results are subject to variance, and small score differences may not be statistically meaningful. | ||
| 1268.0 | vision_style_control overall 2026-10-19 (style control, default view)Observed 2026-10-26 | Configuration: GPT-5.6 Terra (xHigh) Harness: LMArena blind pairwise human votes, Bradley-Terry Evaluator: LMArena Confidence: confirmed Notes: LMArena vision style control leaderboard, overall category, published 2026-10-19 (HF lmarena-ai/leaderboard-dataset @9761a3ce, latest split). Board entry 'GPT-5.6 Terra (xHigh)': rank 37, Arena Score 1268.0 (95% CI 1260.8-1275.3), 11842 votes. Retrieved 2026-10-26. | Source Source: LMArena (lmarena.ai), CC BY 4.0 | |
| 1467.0 | text_style_control overall 2026-10-22 (style control, default view)Observed 2026-10-26 | Configuration: GPT-5.6 Terra (xHigh) Harness: LMArena blind pairwise human votes, Bradley-Terry Evaluator: LMArena Confidence: confirmed Notes: LMArena text style control leaderboard, overall category, published 2026-10-22 (HF lmarena-ai/leaderboard-dataset @9761a3ce, latest split). Board entry 'GPT-5.6 Terra (xHigh)': rank 49, Arena Score 1467.2 (95% CI 1463.0-1471.4), 46470 votes. Retrieved 2026-10-26. | Source Source: LMArena (lmarena.ai), CC BY 4.0 | |
| 80.7 | MMMU-Pro overall (no tools)Observed 2026-10-26 | Configuration: MMMU Pro (no tools), GPT-5.6 Terra column Harness: vendor-reported Evaluator: maker (self-reported) Confidence: self-reported Notes: OpenAI GPT-5.6 launch page (published 2026-07-09), 'Multimodal Eval' table, row 'MMMU Pro (no tools)': GPT-5.6 Sol 83%, Terra 80.7%, Luna 78.4%, GPT-5.5 81.2%. Overall MMMU-Pro, not a vendor 'vision' setting; the 'with tools' row (82%) is not used. Retrieved 2026-10-26. | ||
| 1413.0 | text creative_writing 2026-10-22Observed 2026-10-22 | Configuration: GPT-5.6 Terra (xHigh) Harness: LMArena blind pairwise human votes, Bradley-Terry Evaluator: LMArena Confidence: confirmed Notes: LMArena Text arena, Creative Writing category (no style control), board published 2026-10-22 (HF lmarena-ai/leaderboard-dataset @a467e6b9, text config, latest split). Board entry 'GPT-5.6 Terra (xHigh)' (category creative_writing in text/latest-00000-of-00001.parquet): rank 77 of 416, rating 1413.0 (95% CI 1405.8-1420.1), 9947 votes. Source: LMArena (CC BY 4.0). Retrieved 2026-10-27. | Source Source: LMArena (lmarena.ai), CC BY 4.0 |
Migration checks
No linked migration route is available for this model yet.
Rankings & picks(2)
Cheapest of 2 routes · OpenAI API · cache read $0.200