Gemini 2.5 Pro vs GPT-5.6 Sol
Both are Flagship-tier models, from Google and OpenAI respectively. Gemini 2.5 Pro is the cheaper choice overall at a 4:1 input:output ratio.
Which is cheaper
- Input price: Gemini 2.5 Pro is cheaper ($1.25 vs $4.00).
- Output price: Gemini 2.5 Pro is cheaper ($10.00 vs $20.00).
- Blended, 4:1 input:output ratio: Gemini 2.5 Pro is 58.3% cheaper ($3.00 vs $7.20 per weighted 1M tokens).
Side by side
| Spec | Gemini 2.5 Pro | GPT-5.6 Sol |
|---|---|---|
| Provider | OpenAI | |
| Tier | Flagship | Flagship |
| Context window | 1.05M | 1.05M |
| Max output | 66K | 128K |
| Input $/1M | $1.25 | $4.00 |
| Output $/1M | $10.00 | $20.00 |
| Cache read $/1M | $0.125 | $0.40 |
| Cache write $/1M | — | $5.00 |
| Modalities | text, image | text, image |
Gemini 2.5 Pro. Standard tier, <=200k tokens. >200k tier: input $2.50, output $15.00, cache $0.25/1M; cache storage $4.50/1M tokens/hour. Previous-generation flagship, still fully listed (not deprecated) on the current pricing page -- important reference point for price comparisons.
GPT-5.6 Sol. Short-context rate, for prompts up to 272K input tokens. Above 272K the rate is $8 input / $30 output, cache read $0.80, cache write $10 per 1M. Promotional pricing, stated to run at least through 21 November 2026.
Sources
Gemini 2.5 Pro — verified August 29, 2026
GPT-5.6 Sol — verified August 29, 2026
Full Gemini 2.5 Pro pricing page → · Full GPT-5.6 Sol pricing page →