GPT-5.5 vs Nano Banana Pro (Gemini 3 Pro Image): API Cost Comparison
Compare the API pricing, context windows, features, and real-world cost projections for GPT-5.5 (OpenAI) and Nano Banana Pro (Gemini 3 Pro Image) (Google). Use the interactive calculator below to compute your exact monthly cost based on your token usage and request volume.
Prices verified Jun 26, 2026
Interactive Cost Calculator
Fills in typical token counts for a workload type
Tokens in each prompt sent to the model
Tokens generated in each response
Total API calls per month
Showing costs for 2 models. Cheapest: Nano Banana Pro (Gemini 3 Pro Image) at $80.00/month.
| Alert | |||||||
|---|---|---|---|---|---|---|---|
BestNano Banana Pro (Gemini 3 Pro Image) | $80.00 | $0.008000 | $20.00 | $60.00 | 60.0% | Alerts coming soon | |
GPT-5.5 | OpenAI | $200.00 | $0.020000 | $50.00 | $150.00 | — | Alerts coming soon |
Monthly Cost Comparison
Price Comparison at a Glance
All prices are in USD per 1 million tokens ($/M tokens). Lower is cheaper.
| Pricing Type | GPT-5.5 | Nano Banana Pro (Gemini 3 Pro Image) | Cheaper |
|---|---|---|---|
| Input (standard) | $5.00/M | $2.00/M | Nano Banana Pro (Gemini 3 Pro Image) |
| Output | $30.00/M | $12.00/M | Nano Banana Pro (Gemini 3 Pro Image) |
Prices last verified: 2026-04-30 – 2026-06-26
Cost Breakdown by Usage Volume
Estimated monthly costs at different request volumes, assuming 1,000 input tokens and 500 output tokens per request. Adjust in the calculator above for your specific use case.
| Volume | GPT-5.5Monthly | Nano Banana Pro (Gemini 3 Pro Image)Monthly | GPT-5.5Per request | Nano Banana Pro (Gemini 3 Pro Image)Per request |
|---|---|---|---|---|
| 1K requests/mo | $20.00 | $8.00 | $0.020000 | $0.008000 |
| 10K requests/mo | $200.00 | $80.00 | $0.020000 | $0.008000 |
| 100K requests/mo | $2,000.00 | $800.00 | $0.020000 | $0.008000 |
| 1M requests/mo | $20,000.00 | $8,000.00 | $0.020000 | $0.008000 |
Green values indicate the lower-cost option at each volume tier. Cost per request is calculated at 1,000 input + 500 output tokens using standard (non-batch, non-cached) pricing.
When to Choose GPT-5.5
by OpenAI
- General chatbot
Input / 1M tokens
$5.00/M
Output / 1M tokens
$30.00/M
Context window
1,050,000
Tier
premium
When to Choose Nano Banana Pro (Gemini 3 Pro Image)
by Google
- General chatbot
Input / 1M tokens
$2.00/M
Output / 1M tokens
$12.00/M
Context window
65,536
Tier
mid
Key Differences Beyond Price
Cost is only one factor in choosing an AI model. Context window size, rate limits, supported features, and latency all affect whether a model fits your use case.
| Capability | GPT-5.5 | Nano Banana Pro (Gemini 3 Pro Image) |
|---|---|---|
| Context window | 1,050,000 tokens | 65,536 tokens |
| Max output tokens | 128,000 tokens | 32,768 tokens |
| Performance tier | Premium | Mid |
| Vision / image input | Yes | Yes |
| Function calling | Yes | Yes |
| JSON mode | Yes | Yes |
| Prompt caching | No | No |
| Batch API (50% discount) | No | No |
| Extended reasoning | Yes | Yes |
| Fine-tuning | No | No |
Frequently Asked Questions
Is GPT-5.5 cheaper than Nano Banana Pro (Gemini 3 Pro Image)?
At standard usage (1,000 input tokens, 500 output tokens, 100,000 requests/month), Nano Banana Pro (Gemini 3 Pro Image) costs $800.00/month versus $2,000.00/month for GPT-5.5 — a 60% saving. Your actual savings will vary based on your token profile; output-heavy workloads amplify differences in output pricing.
Which model has a larger context window, GPT-5.5 or Nano Banana Pro (Gemini 3 Pro Image)?
GPT-5.5 has a larger context window at 1,050,000 tokens, compared to 65,536 tokens for Nano Banana Pro (Gemini 3 Pro Image). A larger context window is important for processing long documents, multi-turn conversations, or large codebases without truncation.
Do GPT-5.5 and Nano Banana Pro (Gemini 3 Pro Image) support the Batch API?
Neither GPT-5.5 nor Nano Banana Pro (Gemini 3 Pro Image) currently supports a batch API with discounted pricing. For batch-eligible alternatives, consider models from OpenAI, Anthropic, or Google that include batch API support.
Which model offers better prompt caching?
Neither GPT-5.5 nor Nano Banana Pro (Gemini 3 Pro Image) currently supports prompt caching. For prompt-caching capable alternatives, consider Claude models from Anthropic or GPT-4o from OpenAI.
What are the best use cases for GPT-5.5 vs Nano Banana Pro (Gemini 3 Pro Image)?
Both models are well-suited for General chatbot. GPT-5.5 is particularly strong for overlapping tasks. Nano Banana Pro (Gemini 3 Pro Image) is favored for similar workflows. At the same quality level, the lower-cost model is usually preferable; use this page's calculator to compare total monthly spend at your volume.
What is the cost per request for GPT-5.5 vs Nano Banana Pro (Gemini 3 Pro Image)?
At 1,000 input tokens and 500 output tokens per request — a typical conversational workload — GPT-5.5 costs $0.020000 per request and Nano Banana Pro (Gemini 3 Pro Image) costs $0.008000 per request. At 100,000 requests/month, that translates to $2,000.00 and $800.00 respectively. Use the interactive calculator to adjust these parameters for your actual workload.
GPT-5.5 vs Nano Banana Pro (Gemini 3 Pro Image): Summary
When comparing GPT-5.5 and Nano Banana Pro (Gemini 3 Pro Image) for API cost, the right choice depends on your workload's token profile, required features, and tolerance for latency. Nano Banana Pro (Gemini 3 Pro Image) offers lower total cost at standard usage volumes (1,000 input + 500 output tokens per request at 100,000 requests/month) at $800.00/month, compared to $2,000.00/month for GPT-5.5.
Both models are priced in USD per million tokens, the standard unit across all major AI API providers. GPT-5.5 charges $5.00/M for input tokens and $30.00/M for output tokens. Nano Banana Pro (Gemini 3 Pro Image) charges $2.00/M input and $12.00/M output. If your workload is output-heavy (more tokens generated than consumed as input), the model with the lower output price compounds cost savings significantly at scale.
Context window capacity differs between the two: GPT-5.5 supports up to 1,050,000 tokens in a single request, versus 65,536 tokens for Nano Banana Pro (Gemini 3 Pro Image). A larger context window is essential for document summarization, large codebase analysis, and multi-document retrieval-augmented generation (RAG) applications.
Use the interactive calculator at the top of this page to enter your actual token usage and monthly request volume for a precise cost comparison tailored to your workload. Adjust for batch API discounts and prompt caching to find the most cost-effective option for your specific deployment.
Related Comparisons
Explore other model comparisons from the same providers or performance tiers.
Related Provider Pages
View complete pricing tables and model lineups for the providers behind these models.
Relevant Use Cases
See cost recommendations for workloads where GPT-5.5 or Nano Banana Pro (Gemini 3 Pro Image) is recommended.