Gemini 2.5 Flash vs GPT-5.6 Terra
Both are Mid-tier models, from Google and OpenAI respectively. Gemini 2.5 Flash is the cheaper choice overall at a 4:1 input:output ratio.
Which is cheaper
- Input price: Gemini 2.5 Flash is cheaper ($0.30 vs $2.00).
- Output price: Gemini 2.5 Flash is cheaper ($2.50 vs $12.00).
- Blended, 4:1 input:output ratio: Gemini 2.5 Flash is 81.5% cheaper ($0.74 vs $4.00 per weighted 1M tokens).
Side by side
| Spec | Gemini 2.5 Flash | GPT-5.6 Terra |
|---|---|---|
| Provider | OpenAI | |
| Tier | Mid | Mid |
| Context window | 1M | 1.05M |
| Max output | — | 128K |
| Input $/1M | $0.30 | $2.00 |
| Output $/1M | $2.50 | $12.00 |
| Cache read $/1M | $0.03 | $0.20 |
| Cache write $/1M | — | $2.50 |
| Modalities | text, image | text, image |
Gemini 2.5 Flash. Standard tier, text/image/video rate; audio input $1.00/1M. Cache storage $1.00/1M tokens/hour. Page explicitly states this model supports a 1M token context window.
GPT-5.6 Terra. One flat rate: unlike Sol and Cyber, Terra has no long-context surcharge tier on the pricing page.
Sources
Gemini 2.5 Flash — verified August 29, 2026
GPT-5.6 Terra — verified August 29, 2026
Full Gemini 2.5 Flash pricing page → · Full GPT-5.6 Terra pricing page →