API cost decision in 10 seconds

GPT-5.4 Nano vs GPT-5.1-Codex-Max

Pick GPT-5.4 Nano when budget is the priority.

Page updated: 2026-05-26T10:03:26Z Data confirmed: 2026-05-26T13:08:02Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick GPT-5.4 Nano when budget is the priority.

On the standard 1M input plus 500K output workload, GPT-5.4 Nano is estimated at $0.82 vs $6.25 for GPT-5.1-Codex-Max, saving $5.42 (86.8% lower).

Cost-first pickGPT-5.4 Nano

Context-first pickBoth models

Sample savings$5.4286.8%

10x traffic gap$54.25

The reported context window is tied, so cost and provider fit carry more weight. At 10x that traffic, the same price gap is about $54.25. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

GPT-5.4 Nano stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shape	Token mix	Better pick	GPT-5.4 Nano	GPT-5.1-Codex-Max
Input-heavy / RAG	5M input + 500K output	GPT-5.4 Nano	$1.62	$11.25
Balanced workload	1M input + 1M output	GPT-5.4 Nano	$1.45	$11.25
Output-heavy chatbot	1M input + 5M output	GPT-5.4 Nano	$6.45	$51.25

Cheaper input GPT-5.4 Nano $0.2 vs $1.25 / 1M

GPT-5.4 Nano is $1.05 cheaper per 1M input tokens (84% lower; 6.25x difference).

Cheaper output GPT-5.4 Nano $1.25 vs $10 / 1M

GPT-5.4 Nano is $8.75 cheaper per 1M output tokens (87.5% lower; 8x difference).

Larger context Tie 400K vs 400K

Both models report the same context window at 400K tokens.

Sample workload GPT-5.4 Nano $0.82 vs $6.25

GPT-5.4 Nano is $5.42 cheaper on the standard workload (86.8% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.

Monthly input tokens Monthly output tokens

GPT-5.4 Nano Calculating… Estimated API cost

GPT-5.1-Codex-Max 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-5.4 Nano has the lower input price; GPT-5.4 Nano has the lower output price; both models report the same context window. For the 1M input plus 500K output sample, GPT-5.4 Nano is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $0.82 for GPT-5.4 Nano and $6.25 for GPT-5.1-Codex-Max.

Best Fit

Choose GPT-5.4 Nano when you care most about lower input-token price, and lower output-token price.

Choose GPT-5.1-Codex-Max 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-5.4 Nano is estimated at $0.82 vs $6.25 for GPT-5.1-Codex-Max, saving $5.42 (86.8% lower).
GPT-5.4 Nano is $5.42 cheaper on the standard workload (86.8% lower).
GPT-5.4 Nano is $1.05 cheaper per 1M input tokens (84% lower; 6.25x difference).
GPT-5.4 Nano is $8.75 cheaper per 1M output tokens (87.5% lower; 8x difference).
Both models report the same context window at 400K tokens.

Head-to-Head Specs

Feature	GPT-5.4 Nano (OpenAI)	GPT-5.1-Codex-Max (OpenAI)
Input Price prompt tokens per 1M	$0.2	$1.25
Completion Price per 1M tokens	$1.25	$10
Sample Workload Cost 1M input + 500K output	$0.82	$6.25
Context Window	400K	400K
Release Date	2026-03-17	2025-12-04

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	GPT-5.4 Nano	On the standard 1M input plus 500K output workload, GPT-5.4 Nano is estimated at $0.82 vs $6.25 for GPT-5.1-Codex-Max, saving $5.42 (86.8% lower).
High-volume input processing	GPT-5.4 Nano	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	GPT-5.4 Nano	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	Tie	A 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-5.4 Nano when lower sample workload cost matters most: $0.
gpt-oss-20b (free) can replace GPT-5.4 Nano when lower sample workload cost matters most: $0.
gpt-oss-20b can replace GPT-5.4 Nano when lower sample workload cost matters most: $0.1.
gpt-oss-120b can replace GPT-5.4 Nano 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.
Owl Alpha offers 1.05M context with $0 sample workload cost.

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Provider catalogs

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OpenAI catalog

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GPT-5.4 Nano

GPT-5.4 nano is the most lightweight and cost-efficient variant of the GPT-5.4 family, optimized for speed-critical and high-volume tasks. It supports text and image inputs and is designed for low-latency...

GPT-5.1-Codex-Max

GPT-5.1-Codex-Max is OpenAI’s latest agentic coding model, designed for long-running, high-context software development tasks. It is based on an updated version of the 5.1 reasoning stack and trained on agentic...