API cost decision in 10 seconds

GPT-5.4 Pro vs GPT-5.3-Codex

Pick GPT-5.3-Codex for lower cost; pick GPT-5.4 Pro only if the larger context window matters more.

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

Budget verdict

Pick GPT-5.3-Codex for lower cost; pick GPT-5.4 Pro only if the larger context window matters more.

On the standard 1M input plus 500K output workload, GPT-5.3-Codex is estimated at $8.75 vs $120 for GPT-5.4 Pro, saving $111.25 (92.7% lower).

Cost-first pickGPT-5.3-Codex
Context-first pickGPT-5.4 Pro
Sample savings$111.2592.7%
10x traffic gap$1112.5

GPT-5.4 Pro has more context, but GPT-5.3-Codex saves $111.25 on the standard workload. At 10x that traffic, the same price gap is about $1112.5. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

GPT-5.3-Codex stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shapeToken mixBetter pickGPT-5.4 ProGPT-5.3-Codex
Input-heavy / RAG5M input + 500K outputGPT-5.3-Codex$240$15.75
Balanced workload1M input + 1M outputGPT-5.3-Codex$210$15.75
Output-heavy chatbot1M input + 5M outputGPT-5.3-Codex$930$71.75
Cheaper input GPT-5.3-Codex $30 vs $1.75 / 1M

GPT-5.3-Codex is $28.25 cheaper per 1M input tokens (94.2% lower; 17.1x difference).

Cheaper output GPT-5.3-Codex $180 vs $14 / 1M

GPT-5.3-Codex is $166 cheaper per 1M output tokens (92.2% lower; 12.9x difference).

Larger context GPT-5.4 Pro 1.05M vs 400K

GPT-5.4 Pro has 650K more context (2.62x larger).

Sample workload GPT-5.3-Codex $120 vs $8.75

GPT-5.3-Codex is $111.25 cheaper on the standard workload (92.7% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.
GPT-5.4 Pro Calculating… Estimated API cost
GPT-5.3-Codex 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-5.3-Codex has the lower input price; GPT-5.3-Codex has the lower output price; GPT-5.4 Pro offers the larger context window. For the 1M input plus 500K output sample, GPT-5.3-Codex is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $120 for GPT-5.4 Pro and $8.75 for GPT-5.3-Codex.

Best Fit

Choose GPT-5.4 Pro when you care most about larger context window.

Choose GPT-5.3-Codex when you care most about lower input-token price, and lower output-token price.

Decision Notes
  • On the standard 1M input plus 500K output workload, GPT-5.3-Codex is estimated at $8.75 vs $120 for GPT-5.4 Pro, saving $111.25 (92.7% lower).
  • GPT-5.3-Codex is $111.25 cheaper on the standard workload (92.7% lower).
  • GPT-5.3-Codex is $28.25 cheaper per 1M input tokens (94.2% lower; 17.1x difference).
  • GPT-5.3-Codex is $166 cheaper per 1M output tokens (92.2% lower; 12.9x difference).
  • GPT-5.4 Pro has 650K more context (2.62x larger).
Head-to-Head Specs
FeatureGPT-5.4 Pro
(OpenAI)
GPT-5.3-Codex
(OpenAI)
Input Price
prompt tokens per 1M
$30$1.75
Completion Price
per 1M tokens
$180$14
Sample Workload Cost
1M input + 500K output
$120$8.75
Context Window1.05M400K
Release Date

Use-Case Decision Matrix

Use caseBetter pickWhy
Budget-constrained productionGPT-5.3-CodexOn the standard 1M input plus 500K output workload, GPT-5.3-Codex is estimated at $8.75 vs $120 for GPT-5.4 Pro, saving $111.25 (92.7% lower).
High-volume input processingGPT-5.3-CodexLower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbotsGPT-5.3-CodexLower output-token price matters most when assistants generate many completion tokens.
RAG or long-document workGPT-5.4 ProA 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 Pro when lower sample workload cost matters most: $0.
  • gpt-oss-20b (free) can replace GPT-5.4 Pro when lower sample workload cost matters most: $0.
  • gpt-oss-20b can replace GPT-5.4 Pro when lower sample workload cost matters most: $0.1.
  • gpt-oss-120b can replace GPT-5.4 Pro when lower sample workload cost matters most: $0.13.
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OpenAI catalog

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