GPT-5.3 Codex vs Grok 4.5: Pricing Comparison

Compare pricing, capabilities, and costs for your LLM workloads.

OpenAI

GPT-5.3 Codex

Pricing (per 1M tokens)

Input$1.75
Output$14.00
Cached Input$0.1750

Context & Output

Context Window400K tokens
Max Output128K tokens

Capabilities

Categoryflagship
Multimodaltext + image
Fine-tuningNo
StreamingYes

xAI

Grok 4.5

Pricing (per 1M tokens)

Input$2.00
Output$6.00
Cached Input$0.3000

Context & Output

Context Window500K tokens
Max Output32.8K tokens

Capabilities

Categoryflagship
Multimodaltext + image
Fine-tuningNo
StreamingYes

Quick Verdict

Cheaper Input Price

GPT-5.3 Codex

12.5% cheaper

Cheaper Output Price

Grok 4.5

57.1% cheaper

Larger Context Window

Grok 4.5

+100K tokens

Cost Comparison

Sample workload: 1,000,000 input tokens + 1,000,000 output tokens

GPT-5.3 Codex

$15.75

$1.75/1M input + $14.00/1M output

Grok 4.5

$8.00

$2.00/1M input + $6.00/1M output

Grok 4.5 is 49.2% cheaper for this workload.

Frequently Asked Questions

Which is cheaper, GPT-5.3 Codex or Grok 4.5?
For input tokens, GPT-5.3 Codex is cheaper at $1.75 per 1M tokens. For output tokens, Grok 4.5 is cheaper at $6.00 per 1M tokens. The overall cost depends on your workload's input/output ratio.
What is the context window size of GPT-5.3 Codex vs Grok 4.5?
GPT-5.3 Codex has a context window of 400K tokens, while Grok 4.5 has 500K tokens. Grok 4.5 supports a larger context window of 500K tokens, which is beneficial for processing longer documents.

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