API cost decision in 10 seconds

GPT-5.1-Codex-Max vs Nano Banana Pro (Gemini 3 Pro Image Preview)

Pick GPT-5.1-Codex-Max when budget and context both matter.

Page updated:  Data confirmed:  Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick GPT-5.1-Codex-Max when budget and context both matter.

On the standard 1M input plus 500K output workload, GPT-5.1-Codex-Max is estimated at $6.25 vs $8 for Nano Banana Pro (Gemini 3 Pro Image Preview), saving $1.75 (21.9% lower).

Cost-first pickGPT-5.1-Codex-Max
Context-first pickGPT-5.1-Codex-Max
Sample savings$1.7521.9%
10x traffic gap$17.5

GPT-5.1-Codex-Max is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $17.5. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

GPT-5.1-Codex-Max stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shapeToken mixBetter pickGPT-5.1-Codex-MaxNano Banana Pro (Gemini 3 Pro Image Preview)
Input-heavy / RAG5M input + 500K outputGPT-5.1-Codex-Max$11.25$16
Balanced workload1M input + 1M outputGPT-5.1-Codex-Max$11.25$14
Output-heavy chatbot1M input + 5M outputGPT-5.1-Codex-Max$51.25$62
Cheaper input GPT-5.1-Codex-Max $1.25 vs $2 / 1M

GPT-5.1-Codex-Max is $0.75 cheaper per 1M input tokens (37.5% lower; 1.6x difference).

Cheaper output GPT-5.1-Codex-Max $10 vs $12 / 1M

GPT-5.1-Codex-Max is $2 cheaper per 1M output tokens (16.7% lower; 1.2x difference).

Larger context GPT-5.1-Codex-Max 400K vs 65.54K

GPT-5.1-Codex-Max has 334.46K more context (6.1x larger).

Sample workload GPT-5.1-Codex-Max $6.25 vs $8

GPT-5.1-Codex-Max is $1.75 cheaper on the standard workload (21.9% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.
GPT-5.1-Codex-Max Calculating… Estimated API cost
Nano Banana Pro (Gemini 3 Pro Image Preview) Calculating… Estimated API cost
Cheaper for this workload Calculating… Difference: calculating…

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

Verdict

GPT-5.1-Codex-Max has the lower input price; GPT-5.1-Codex-Max has the lower output price; GPT-5.1-Codex-Max offers the larger context window. For the 1M input plus 500K output sample, GPT-5.1-Codex-Max is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $6.25 for GPT-5.1-Codex-Max and $8 for Nano Banana Pro (Gemini 3 Pro Image Preview).

Best Fit

Choose GPT-5.1-Codex-Max when you care most about lower input-token price, lower output-token price, and larger context window.

Choose Nano Banana Pro (Gemini 3 Pro Image Preview) when its provider, model quality, latency, or availability is more important than the numeric price/context winner.

Decision Notes
  • On the standard 1M input plus 500K output workload, GPT-5.1-Codex-Max is estimated at $6.25 vs $8 for Nano Banana Pro (Gemini 3 Pro Image Preview), saving $1.75 (21.9% lower).
  • GPT-5.1-Codex-Max is $1.75 cheaper on the standard workload (21.9% lower).
  • GPT-5.1-Codex-Max is $0.75 cheaper per 1M input tokens (37.5% lower; 1.6x difference).
  • GPT-5.1-Codex-Max is $2 cheaper per 1M output tokens (16.7% lower; 1.2x difference).
  • GPT-5.1-Codex-Max has 334.46K more context (6.1x larger).
Head-to-Head Specs
FeatureGPT-5.1-Codex-Max
(OpenAI)
Nano Banana Pro (Gemini 3 Pro Image Preview)
(Google)
Input Price
prompt tokens per 1M
$1.25$2
Completion Price
per 1M tokens
$10$12
Sample Workload Cost
1M input + 500K output
$6.25$8
Context Window400K65.54K
Release Date

Use-Case Decision Matrix

Use caseBetter pickWhy
Budget-constrained productionGPT-5.1-Codex-MaxOn the standard 1M input plus 500K output workload, GPT-5.1-Codex-Max is estimated at $6.25 vs $8 for Nano Banana Pro (Gemini 3 Pro Image Preview), saving $1.75 (21.9% lower).
High-volume input processingGPT-5.1-Codex-MaxLower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbotsGPT-5.1-Codex-MaxLower output-token price matters most when assistants generate many completion tokens.
RAG or long-document workGPT-5.1-Codex-MaxA larger context window leaves more room for retrieved passages, conversation history, or source files.

Related Alternatives

Same-provider lower-cost swaps
  • gpt-oss-120b (free) can replace GPT-5.1-Codex-Max when lower sample workload cost matters most: $0.
  • gpt-oss-20b (free) can replace GPT-5.1-Codex-Max when lower sample workload cost matters most: $0.
  • gpt-oss-20b can replace GPT-5.1-Codex-Max when lower sample workload cost matters most: $0.1.
  • gpt-oss-120b can replace GPT-5.1-Codex-Max when lower sample workload cost matters most: $0.13.
Larger context near this budget
  • 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.

Cheaper alternatives

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Larger context alternatives

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Provider catalogs

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OpenAI catalog

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Google catalog

Check other Google models with comparable pricing, context, or release timing.

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GPT-5.1-Codex-Max

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