GPT-5.6 Sol vs GPT-5.6 Terra: which is better for agents?

GPT-5.6 Sol scores higher on output quality (8.6/10 vs 8.0/10), while GPT-5.6 Sol is the cheaper option. GPT-5.6 Sol is best for existing GPT-5.6 Sol setups until they move to GPT-6.1 Sol; GPT-5.6 Terra is best for fast mid-tier work in existing GPT-5.6 setups. Live community votes on this page show what people actually prefer.

Is GPT-5.6 Sol cheaper than GPT-5.6 Terra?

GPT-5.6 Sol is cheaper: roughly $4.40 vs $5.00 per 1M tokens (blended). GPT-5.6 Sol: $2.00 in · $10 out / 1M tokens. GPT-5.6 Terra: $2.00 in · $12 out / 1M tokens.

Can I switch between GPT-5.6 Sol and GPT-5.6 Terra in the same agent?

Yes. Model-agnostic agents (Cline, Aider, OpenClaw, Hermes Agent, Kilo Code, OpenCode) let you swap models per task. Many people route hard tasks to the stronger model and routine work to the cheaper one.

Model comparison 2026

GPT-5.6 Sol vs GPT-5.6 Terra

GPT-5.6 Sol

OpenAI · Frontier · Proprietary

$4.40/1M · 1.1M ctx

GPT-5.6 Terra

OpenAI · Balanced · Proprietary

$5.00/1M · 1.1M ctx

Community vote

Pick a winner in each dimension. You can change your vote any time.

Output Quality

Correctness and depth of what it produces

Agentic Ability

Tool calls, instruction-following, and multi-step tasks

Speed

Tokens per second and time-to-first-token

Value for Money

How much capability you get per dollar

Reliability

Consistent results: fewer refusals, loops and format breaks

Specs and pricing side by side

Spec

GPT-5.6 Sol

GPT-5.6 Terra

Maker

OpenAI

Blended price / 1M

$4.40

$5.00

Input / output

$2.00 in · $10 out / 1M tokens

$2.00 in · $12 out / 1M tokens

Context window

1.1M

Open weights

Tool use

Yes

Reasoning

Yes

Output Quality

8.6

8.0

Agentic Ability

7.9

7.8

Speed

7.6

8.4

Value for Money

4.6

5.2

Reliability

9.2

Pricing and capabilities synced from the OpenRouter catalogue. Scores are editorial (0–10).

Verdict: GPT-5.6 Sol or GPT-5.6 Terra?

Updated 2026-10-14

Choose GPT-5.6 Sol if you want existing GPT-5.6 Sol setups until they move to GPT-6.1 Sol. Choose GPT-5.6 Terra if you want fast mid-tier work in existing GPT-5.6 setups.

Editorially it's close: each model leads in 2 of our five dimensions. On price, GPT-5.6 Sol runs about $4.40 per 1M tokens (blended) and is proprietary; GPT-5.6 Terra is about $5.00 and proprietary.

Where GPT-5.6 Sol falls short