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PricesCompare → GPT-5.3 Codex vs Claude Haiku 4.5

GPT-5.3 Codex vs Claude Haiku 4.5: API cost compared

GPT-5.3 Codex lists at $1.750 in / $14.00 out per 1M tokens. Claude Haiku 4.5 lists at $1.000 in / $5.000. Sticker price only tells you so much — below is what each actually costs across eight production workloads.

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Cheaper on more workloads
Claude Haiku 4.5
wins 8 of 8
Blended rate gap
2.4x
at 3:1 in:out

Side by side

GPT-5.3 CodexClaude Haiku 4.5
ProviderOpenAIAnthropic
Input per 1M$1.750$1.000
Output per 1M$14.00$5.000
Cached input per 1M$0.175$0.100
Context window400k200k
Blended per 1M (3:1)$4.812$2.000

Monthly cost by workload

Caching applied at each workload's typical hit rate. This is where the two models actually separate.

WorkloadGPT-5.3 CodexClaude Haiku 4.5CheaperDifference
Customer support chatbot$317.45$128.90Claude Haiku 4.5$188.55 (59%)
RAG document Q&A$385.00$184.00Claude Haiku 4.5$201.00 (52%)
Coding agent$224.88$92.50Claude Haiku 4.5$132.38 (59%)
Bulk summarization$2,566$1,346Claude Haiku 4.5$1,220 (48%)
Structured data extraction$3,710$1,745Claude Haiku 4.5$1,965 (53%)
Long-form content generation$585.55$214.60Claude Haiku 4.5$370.95 (63%)
Email triage agent$861.87$402.50Claude Haiku 4.5$459.37 (53%)
Translation pipeline$3,718$1,405Claude Haiku 4.5$2,314 (62%)
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How to read this

Claude Haiku 4.5 is cheaper on the majority of these workloads, but "majority" is not the decision. The output:input price ratio is 8.0 for GPT-5.3 Codex and 5.0 for Claude Haiku 4.5. If your traffic is output-heavy — long-form drafting, translation — the model with the lower output price wins regardless of what the input price suggests. If you are input-heavy — RAG, bulk summarization, agents re-reading a codebase — the cached input rate matters more than either headline number.

Cost is also not the only axis. This site does not benchmark quality, latency, or rate limits, and a model that is 3x cheaper but needs two attempts per task is not cheaper. Use these numbers to size a bill, then validate on your own evals.

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Cost calculator

Enter your own numbers, or start from a workload preset. Costs are monthly and update as you type.

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