Adjustable Reasoning Effort
Reasoning effort scales from none to max per request, so one gpt-5.6-terra deployment covers quick lookups and multi-step analysis without switching models or renegotiating cost.
curl --request POST "https://gptproto.com/v1/chat/completions" \
--header "Authorization: Bearer $GPTPROTO_API_KEY" \
--header "Content-Type: application/json" \
--data '{
"model": "gpt-5.6-terra",
"messages": [
{
"role": "user",
"content": "Hello"
}
]
}'Estimate a request with real work scenarios. GPTProto token pricing is 20% below official rates.
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GPTProto vs official pricing.Save$25.00 (20%)vs OpenAI official
The balanced tier of OpenAI's GPT-5.6 family — GPT-5.5-competitive quality at half the official price, 20% cheaper again on GPTProto.
Reasoning effort scales from none to max per request, so one gpt-5.6-terra deployment covers quick lookups and multi-step analysis without switching models or renegotiating cost.
OpenAI positions gpt-5.6-terra as competitive with GPT-5.5: 87.4% on Terminal-Bench 2.1 and 77 on the Artificial Analysis Coding Agent Index — at half GPT-5.5's official token price.
Strict schema mode returns JSON that conforms to your spec on every call — suited to ETL, extraction, and API orchestration where one malformed field breaks downstream systems.
gpt-5.6-terra accepts up to 1,050,000 input tokens with 128K max output. Load full document sets into a single RAG request instead of chunking across calls.
GPT 5.6 Terra is the middle tier of OpenAI's GPT-5.6 family, released to general availability on July 9, 2026 alongside gpt-5.6-sol (flagship) and gpt-5.6-luna (fastest, cheapest). It corresponds to the mini tier of earlier GPT-5 generations and targets the bulk of production traffic: customer support, internal tools, document analysis, and everyday agentic coding where the flagship's higher ceiling isn't needed.
The openai gpt 5.6 terra api runs on GPTProto with the same model string and OpenAI-compatible schema — no separate OpenAI account, no additional security enrollment, one API key that also covers Sol, Luna, and 200+ other models.
| Spec | gpt-5.6-terra |
|---|---|
| Provider | OpenAI |
| Modality | Text & Image in / text out |
| Context window | 1,050,000 tokens |
| Max output | 128,000 tokens |
| Knowledge cutoff | February 16, 2026 |
| Reasoning effort | none / low / medium / high / xhigh / max |
| Structured outputs | Strict JSON schema mode |
| Tool use | Programmatic Tool Calling (Responses API) |
| GPTProto price | $2 input / $12 output per 1M tokens |
| Official price | $2.50 input / $15 output per 1M tokens |
| Model string | gpt-5.6-terra |
If you searched for the gpt 5.6 terra api token limit: the numbers above are OpenAI's published caps — 1.05M in, 128K out. Requests above 272K input tokens are priced at 2x input / 1.5x output on OpenAI's official API.
| gpt-5.6-terra | gpt-5.5 | |
|---|---|---|
| Terminal-Bench 2.1 | 87.4% | 88.0% |
| SWE-Bench Pro | 63.4% | 58.6% |
| Artificial Analysis Intelligence Index | 55 | 55 |
| Artificial Analysis Coding Agent Index | 77 (Codex harness) | 76 (Codex harness) |
| Official price per 1M | $2.50 / $15 | $5 / $30 |
| GPTProto price per 1M | $2 / $12 | $4 / $24 |
The two models tie on the Artificial Analysis Intelligence Index and split the coding benchmarks — a 0.6-point Terminal-Bench gap against a 4.8-point SWE-Bench Pro lead for Terra. At half the price, cheaper gpt 5.6 terra api access is the default recommendation for teams currently running GPT-5.5 in production; keep gpt-5.5 as a rollback string during migration.
For the full three-tier family comparison (Sol vs Terra vs Luna), see the table on the gpt-5.6-sol page.
| Workload | Input | Output | GPTProto cost | Official cost |
|---|---|---|---|---|
| Document analysis run | 200K | 10K | $0.52 | $0.65 |
| Daily batch job | 10M | 1M | $32.00 | $40.00 |
| Support bot, monthly | 100M | 20M | $440.00 | $550.00 |
Get answers to common questions about the gpt 5.6 terra api: pricing on GPTProto, context window and token limits, structured JSON output, and how Terra compares with Sol and GPT-5.5.
Guides, comparisons, and updates related to this model.
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