Gemini 2.5 Flash is $4.7 cheaper per 1M input tokens (94% lower; 16.7x difference).
API cost decision in 10 seconds
🔥Gemini 2.5 Flash vs 🔥GPT-5.5
Pick Gemini 2.5 Flash for lower cost; pick GPT-5.5 only if the larger context window matters more.
Pricing data updated:
Prices normalized to USD per 1M tokens
Sample workload: 1M input + 500K output
Budget verdict
Pick Gemini 2.5 Flash for lower cost; pick GPT-5.5 only if the larger context window matters more.
On the standard 1M input plus 500K output workload, Gemini 2.5 Flash is estimated at $1.55 vs $20 for GPT-5.5, saving $18.45 (92.2% lower).
Cost-first pickGemini 2.5 Flash
Context-first pickGPT-5.5
Sample savings$18.4592.2%
10x traffic gap$184.5
GPT-5.5 has more context, but Gemini 2.5 Flash saves $18.45 on the standard workload. At 10x that traffic, the same price gap is about $184.5. Use the calculator below to replace the sample workload with your own token volume.
Gemini 2.5 Flash is $27.5 cheaper per 1M output tokens (91.7% lower; 12x difference).
GPT-5.5 has 1.42K more context (1x larger).
Gemini 2.5 Flash is $18.45 cheaper on the standard workload (92.2% lower).
Estimate your workload cost
Your Workload Cost
This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.
Quick Decision
Gemini 2.5 Flash has the lower input price; Gemini 2.5 Flash has the lower output price; GPT-5.5 offers the larger context window. For the 1M input plus 500K output sample, Gemini 2.5 Flash is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $1.55 for Gemini 2.5 Flash and $20 for GPT-5.5.
Choose Gemini 2.5 Flash when you care most about lower input-token price, and lower output-token price.
Choose GPT-5.5 when you care most about larger context window.
- On the standard 1M input plus 500K output workload, Gemini 2.5 Flash is estimated at $1.55 vs $20 for GPT-5.5, saving $18.45 (92.2% lower).
- Gemini 2.5 Flash is $18.45 cheaper on the standard workload (92.2% lower).
- Gemini 2.5 Flash is $4.7 cheaper per 1M input tokens (94% lower; 16.7x difference).
- Gemini 2.5 Flash is $27.5 cheaper per 1M output tokens (91.7% lower; 12x difference).
- GPT-5.5 has 1.42K more context (1x larger).
| Feature | 🔥Gemini 2.5 Flash (Google) | 🔥GPT-5.5 (OpenAI) |
|---|---|---|
| Input Price prompt tokens per 1M | $0.3 | $5 |
| Completion Price per 1M tokens | $2.5 | $30 |
| Sample Workload Cost 1M input + 500K output | $1.55 | $20 |
| Context Window | 1.05M | 1.05M |
| Release Date | 2025-06-17 | 2026-04-24 |
| Popularity Rank current rank | #13 | #19 |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | Gemini 2.5 Flash | On the standard 1M input plus 500K output workload, Gemini 2.5 Flash is estimated at $1.55 vs $20 for GPT-5.5, saving $18.45 (92.2% lower). |
| High-volume input processing | Gemini 2.5 Flash | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | Gemini 2.5 Flash | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | GPT-5.5 | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
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