GPT 5.6 Terra pricing for chain of thought

Quick start

Call GPT 5.6 Terra with the OpenAI Python SDK:

from openai import OpenAI

client = OpenAI()
response = client.chat.completions.create(
    model="gpt-5.6-terra",
    max_tokens=5000,
    messages=[{"role": "user", "content": "Your prompt here"}]
)
# Cost: ~$0.0660 per call at standard rates
# Input:  $2.00/MTok
# Output: $12.00/MTok

How GPT 5.6 Terra compares on cost

Per-call cost for all models scoring 50+ on chain of thought benchmarks. Hover for details.

Cheapest viable option: GPT 5.6 Luna at $0.006600/call (90% less, 86/100 quality).

What drives chain of thought cost

Reasoning tasks invert the usual ratio: the model produces far more tokens than it consumes, because the intermediate steps are the work. Output pricing dominates completely, and models that reason at length cost more than their headline rate suggests. Comparing reasoning models on input price is actively misleading; compare them on output.

For GPT 5.6 Terra specifically, that means output tokens cost 6.0x more than input, at $12.00 vs $2.00 per MTok. At this use case’s 3,000/5,000 token split, output accounts for 91% of the $0.0660 per-call cost.

GPT 5.6 Terra quality benchmarks for chain of thought

Performance across all task types

GPT 5.6 Terra scores by task type. Chain of Thought highlighted.

Confidence scores are a third-party benchmark snapshot from week 26 of 2026. This snapshot is 17 weeks old, so treat the scores as directional and validate against your own evals.

About GPT 5.6 Terra

Other models from GPT

You can compare GPT 5.6 Terra head-to-head against any other model on our model comparison pages, or track how pricing has changed over time on the pricing history tracker.

Frequently asked questions