GPT-6 Sol vs Gemini 3.8 Flash: API cost
Standard, cached and batch API prices for GPT-6 Sol (OpenAI) and Gemini 3.8 Flash (Google), and what each costs for your usage.
Gemini 3.8 Flash is cheaper than GPT-6 Sol at standard rates, with 2.7× cheaper input and 2.7× cheaper output.
- Input $60.00
- Cached input $6.00
- Output $90.00
- Input $22.50
- Cached input $2.25
- Output $33.75
Show as a table
| Output tokens | GPT-6 Sol | Gemini 3.8 Flash |
|---|---|---|
| 0 | $2.00 | $0.75 |
| 250 | $4.50 | $1.69 |
| 500 | $7.00 | $2.63 |
| 750 | $9.50 | $3.56 |
| 1,000 | $12.00 | $4.50 |
| Token type | GPT-6 Sol | Gemini 3.8 Flash | |
|---|---|---|---|
| Input | $2 | $0.75 | Gemini 3.8 Flash is 2.7× cheaper |
| Cached input | $0.20 | $0.075 | Gemini 3.8 Flash is 2.7× cheaper |
| Output | $10 | $3.75 | Gemini 3.8 Flash is 2.7× cheaper |
| Batch input | $1 | $0.375 | Gemini 3.8 Flash is 2.7× cheaper |
| Batch cached input | $0.10 | $0.0375 | Gemini 3.8 Flash is 2.7× cheaper |
| Batch output | $5 | $1.875 | Gemini 3.8 Flash is 2.7× cheaper |
GPT-6 Sol: Long prompts are billed at higher long-context rates.
Gemini 3.8 Flash: promotional price until 31 Dec 2026.
| Workload | GPT-6 Sol | Gemini 3.8 Flash |
|---|---|---|
Support chatbot 2,000 in / 300 out tokens,
1,000 requests a day, 50% cached | $156.00 | $58.50 |
Document summaries 10,000 in / 800 out tokens,
200 requests a day | $168.00 | $63.00 |
Tagging / classifying 400 in / 20 out tokens,
20,000 requests a day | $600.00 | $225.00 |
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Or see GPT-6 Sol pricing, Gemini 3.8 Flash pricing, or compare any two models.
FAQ
Frequently asked questions
Is GPT-6 Sol cheaper than Gemini 3.8 Flash?
Gemini 3.8 Flash is cheaper than GPT-6 Sol at standard rates, with 2.7× cheaper input and 2.7× cheaper output. Based on standard API rates last checked on 29 Sept 2026.
How much do GPT-6 Sol and Gemini 3.8 Flash cost per million tokens?
GPT-6 Sol: $2 per million input tokens and $10 per million output tokens. Gemini 3.8 Flash: $0.75 input and $3.75 output. These are standard rates in USD, before tax, from each provider’s own pricing page.
Which is cheaper with the Batch API?
GPT-6 Sol’s batch rates are $1 input and $5 output per million tokens (50% off); Gemini 3.8 Flash’s batch rates are $0.375 input and $1.875 output per million tokens (50% off).
Does prompt caching change the comparison?
GPT-6 Sol charges $0.20 per million cached input tokens, against $2 for normal input; Gemini 3.8 Flash charges $0.075 per million cached input tokens, against $0.75 for normal input. Cache write and storage charges are extra and aren’t included here.