AI cost · OpenAI
OpenAI API cost: what you actually pay
Pure usage-based: the bill is tokens × model. The trap is running everything on the flagship, verbose prompts, and skipping caching and the Batch discount.
Public pricing
Token rates (USD per 1M tokens)
| Model | Input | Output | Cache read |
|---|---|---|---|
| GPT-5.5Flagship; standard rates for context < 270K tokens. | $5 | $30 | — |
| GPT-5.4 | $2.5 | $15 | — |
| GPT-5.4 miniLowest-cost tier for most workloads. | $0.75 | $4.5 | — |
Batch API is ~50% cheaper; data-residency processing carries a ~10% markup; rates shown are standard processing for context under 270K tokens.
Last updated: 2026-07-22. Sourced from OpenAI API pricing (official) ↗.
Where the real OpenAI API cost hides
The sticker is the smallest part of the story. For OpenAI API, these are the line items that quietly inflate the bill:
- Running flagship (GPT-5.5) where a mini/mid model suffices
- No prompt caching and no Batch discount on eligible jobs
- Runaway agent loops and untracked/leaked API keys
What an audit finds on OpenAI API
A few services pinned to the flagship model that could run on 5.4 or mini, no batching on bulk jobs, and usage with no per-team attribution.
OpenAI API pricing FAQ
How is the OpenAI API priced?
Per token, by model — e.g., GPT-5.5 at $5 in / $30 out per million tokens, down to GPT-5.4 mini at $0.75 / $4.50.
What is the cheapest way to cut OpenAI API cost?
Right-size the model, cache repeated context, and use the Batch API (~50% off) for non-interactive jobs.
What is OpenAI API really costing you?
Spendassay connects your OpenAI API spend to actual usage and engineering output — a proof-level AI cost report with the wasted dollars named. Neutral across every AI vendor.
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Other api platforms pricing
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