GPT-5.1 Chat is $0.25 cheaper per 1M input tokens (16.7% lower; 1.2x difference).
API cost decision in 10 seconds
Google Gemini Flash Latest vs GPT-5.1 Chat
Pick Google Gemini Flash Latest when budget and context both matter.
Pricing data updated:
Prices normalized to USD per 1M tokens
Sample workload: 1M input + 500K output
Budget verdict
Pick Google Gemini Flash Latest when budget and context both matter.
On the standard 1M input plus 500K output workload, Google Gemini Flash Latest is estimated at $6 vs $6.25 for GPT-5.1 Chat, saving $0.25 (4% lower).
Cost-first pickGoogle Gemini Flash Latest
Context-first pickGoogle Gemini Flash Latest
Sample savings$0.254%
10x traffic gap$2.5
Google Gemini Flash Latest is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $2.5. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
Cost winner changes by workload shape: input-heavy / RAG favors GPT-5.1 Chat, balanced workload favors Google Gemini Flash Latest, and output-heavy chatbot favors Google Gemini Flash Latest.
| Workload shape | Token mix | Better pick | Google Gemini Flash Latest | GPT-5.1 Chat |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | GPT-5.1 Chat | $12 | $11.25 |
| Balanced workload | 1M input + 1M output | Google Gemini Flash Latest | $10.5 | $11.25 |
| Output-heavy chatbot | 1M input + 5M output | Google Gemini Flash Latest | $46.5 | $51.25 |
Google Gemini Flash Latest is $1 cheaper per 1M output tokens (10% lower; 1.11x difference).
Google Gemini Flash Latest has 920.58K more context (8.19x larger).
Google Gemini Flash Latest is $0.25 cheaper on the standard workload (4% 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
GPT-5.1 Chat has the lower input price; Google Gemini Flash Latest has the lower output price; Google Gemini Flash Latest offers the larger context window. For the 1M input plus 500K output sample, Google Gemini Flash Latest is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $6 for Google Gemini Flash Latest and $6.25 for GPT-5.1 Chat.
Choose Google Gemini Flash Latest when you care most about lower output-token price, and larger context window.
Choose GPT-5.1 Chat when you care most about lower input-token price.
- On the standard 1M input plus 500K output workload, Google Gemini Flash Latest is estimated at $6 vs $6.25 for GPT-5.1 Chat, saving $0.25 (4% lower).
- Google Gemini Flash Latest is $0.25 cheaper on the standard workload (4% lower).
- GPT-5.1 Chat is $0.25 cheaper per 1M input tokens (16.7% lower; 1.2x difference).
- Google Gemini Flash Latest is $1 cheaper per 1M output tokens (10% lower; 1.11x difference).
- Google Gemini Flash Latest has 920.58K more context (8.19x larger).
| Feature | Google Gemini Flash Latest (Google) | GPT-5.1 Chat (OpenAI) |
|---|---|---|
| Input Price prompt tokens per 1M | $1.5 | $1.25 |
| Completion Price per 1M tokens | $9 | $10 |
| Sample Workload Cost 1M input + 500K output | $6 | $6.25 |
| Context Window | 1.05M | 128K |
| Release Date |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | Google Gemini Flash Latest | On the standard 1M input plus 500K output workload, Google Gemini Flash Latest is estimated at $6 vs $6.25 for GPT-5.1 Chat, saving $0.25 (4% lower). |
| High-volume input processing | GPT-5.1 Chat | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | Google Gemini Flash Latest | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | Google Gemini Flash Latest | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
Related Alternatives
- Gemma 4 26B A4B (free) can replace Google Gemini Flash Latest when lower sample workload cost matters most: $0.
- Gemma 4 31B (free) can replace Google Gemini Flash Latest when lower sample workload cost matters most: $0.
- Lyria 3 Pro Preview can replace Google Gemini Flash Latest when lower sample workload cost matters most: $0.
- Lyria 3 Clip Preview can replace Google Gemini Flash Latest when lower sample workload cost matters most: $0.
- Llama 4 Scout offers 10M context with $0.23 sample workload cost.
- Grok 4.20 Multi-Agent offers 2M context with $5 sample workload cost.
- Grok 4.20 offers 2M context with $2.5 sample workload cost.
- Owl Alpha offers 1.05M context with $0 sample workload cost.
- No popular competitor is currently available.
Cheaper alternatives
Review low-cost models sorted by a standard 1M input plus 500K output workload.
Open cheapest modelsLarger context alternatives
Find models with larger context windows for RAG, long documents, and codebase review.
Open largest context modelsProvider catalogs
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Open provider hubsGoogle catalog
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Open Google modelsOpenAI catalog
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Open OpenAI modelsThis model always redirects to the latest model in the Google Gemini Flash family.
GPT-5.1 Chat (AKA Instant is the fast, lightweight member of the 5.1 family, optimized for low-latency chat while retaining strong general intelligence. It uses adaptive reasoning to selectively “think” on...