GPT-5.3 Chat is $0.25 cheaper per 1M input tokens (12.5% lower; 1.14x difference).
API cost decision in 10 seconds
GPT-5.3 Chat vs Gemini 3.1 Pro Preview
Pick Gemini 3.1 Pro Preview when budget and context both matter.
Budget verdict
Pick Gemini 3.1 Pro Preview when budget and context both matter.
On the standard 1M input plus 500K output workload, Gemini 3.1 Pro Preview is estimated at $8 vs $8.75 for GPT-5.3 Chat, saving $0.75 (8.6% lower).
Gemini 3.1 Pro Preview is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $7.5. 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-5.3 Chat, balanced workload favors Gemini 3.1 Pro Preview, and output-heavy chatbot favors Gemini 3.1 Pro Preview.
| Workload shape | Token mix | Better pick | GPT-5.3 Chat | Gemini 3.1 Pro Preview |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | GPT-5.3 Chat | $15.75 | $16 |
| Balanced workload | 1M input + 1M output | Gemini 3.1 Pro Preview | $15.75 | $14 |
| Output-heavy chatbot | 1M input + 5M output | Gemini 3.1 Pro Preview | $71.75 | $62 |
Gemini 3.1 Pro Preview is $2 cheaper per 1M output tokens (14.3% lower; 1.17x difference).
Gemini 3.1 Pro Preview has 920.58K more context (8.19x larger).
Gemini 3.1 Pro Preview is $0.75 cheaper on the standard workload (8.6% 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-5.3 Chat has the lower input price; Gemini 3.1 Pro Preview has the lower output price; Gemini 3.1 Pro Preview offers the larger context window. For the 1M input plus 500K output sample, Gemini 3.1 Pro Preview is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $8.75 for GPT-5.3 Chat and $8 for Gemini 3.1 Pro Preview.
Choose GPT-5.3 Chat when you care most about lower input-token price.
Choose Gemini 3.1 Pro Preview when you care most about lower output-token price, and larger context window.
- On the standard 1M input plus 500K output workload, Gemini 3.1 Pro Preview is estimated at $8 vs $8.75 for GPT-5.3 Chat, saving $0.75 (8.6% lower).
- Gemini 3.1 Pro Preview is $0.75 cheaper on the standard workload (8.6% lower).
- GPT-5.3 Chat is $0.25 cheaper per 1M input tokens (12.5% lower; 1.14x difference).
- Gemini 3.1 Pro Preview is $2 cheaper per 1M output tokens (14.3% lower; 1.17x difference).
- Gemini 3.1 Pro Preview has 920.58K more context (8.19x larger).
| Feature | GPT-5.3 Chat (OpenAI) | Gemini 3.1 Pro Preview (Google) |
|---|---|---|
| Input Price prompt tokens per 1M | $1.75 | $2 |
| Completion Price per 1M tokens | $14 | $12 |
| Sample Workload Cost 1M input + 500K output | $8.75 | $8 |
| Context Window | 128K | 1.05M |
| Release Date |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | Gemini 3.1 Pro Preview | On the standard 1M input plus 500K output workload, Gemini 3.1 Pro Preview is estimated at $8 vs $8.75 for GPT-5.3 Chat, saving $0.75 (8.6% lower). |
| High-volume input processing | GPT-5.3 Chat | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | Gemini 3.1 Pro Preview | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | Gemini 3.1 Pro Preview | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
Related Alternatives
- gpt-oss-120b (free) can replace GPT-5.3 Chat when lower sample workload cost matters most: $0.
- gpt-oss-20b (free) can replace GPT-5.3 Chat when lower sample workload cost matters most: $0.
- gpt-oss-20b can replace GPT-5.3 Chat when lower sample workload cost matters most: $0.1.
- gpt-oss-120b can replace GPT-5.3 Chat when lower sample workload cost matters most: $0.13.
- 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.
- GPT-5.4 offers 1.05M context with $10 sample workload cost.
- No popular competitor is currently available.
Cheaper alternatives
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Open Google modelsGPT-5.3 Chat is an update to ChatGPT's most-used model that makes everyday conversations smoother, more useful, and more directly helpful. It delivers more accurate answers with better contextualization and significantly...
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