Standard Compute
Model comparison 2026

Gemini 3.8 Flash vs GPT-5.6 Terra

Gemini 3.8 Flash
Google · Balanced · Proprietary
$1.65/1M · 1.0M 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
Gemini 3.8 Flash
GPT-5.6 Terra
Maker
Google
OpenAI
Blended price / 1M
$1.65
$5.00
Input / output
$0.75 in · $3.75 out / 1M tokens
$2.00 in · $12 out / 1M tokens
Context window
1.0M
1.1M
Open weights
No
No
Tool use
Yes
Yes
Reasoning
Yes
Yes
Output Quality
9.1
9.0
Agentic Ability
8.9
9.0
Speed
9.2
8.4
Value for money
8.8
8.8
Reliability
8.9
9.2

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

Verdict: Gemini 3.8 Flash or GPT-5.6 Terra?

Updated 2026-10-13

Choose Gemini 3.8 Flash if you want high-throughput agents and Gemini CLI users who want speed and big context. Choose GPT-5.6 Terra if you want the everyday OpenAI default for agents — volume work with frontier-adjacent quality.

Editorially it's close: each model leads in 2 of our five dimensions. On price, Gemini 3.8 Flash runs about $1.65 per 1M tokens (blended) and is proprietary; GPT-5.6 Terra is about $5.00 and proprietary.

Where Gemini 3.8 Flash falls short
  • Price doubles to $1.50/$7.50 on January 1, 2027
  • Weak on long terminal tasks (19.1% on Terminal-Bench 4.0)
Full Gemini 3.8 Flash breakdown →
Where GPT-5.6 Terra falls short
  • Steps behind Sol on the hardest tasks
  • GPT-6.1 Sol now costs about the same ($2/$10) and scores far higher
Full GPT-5.6 Terra breakdown →

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