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.
Worked example: OpenAI API at production volume
Take 50M input and 10M output tokens a month — a modest production workload, and a round number we picked — on GPT-5.5 at the published rates above.
- Monthly
- $550
- Annual
- $6,600
- On GPT-5.4 mini
- $83
Same volume, $5,610 a year apart. Most workloads are a mix — some of it genuinely needs the frontier model and some of it does not — so the real question is what share of your calls is the routine kind, and that is a measurement, not a guess.
Arithmetic on the published prices above. Your mix will differ — run your own numbers.
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.
How much can routing cut a OpenAI API bill?
On 50M input and 10M output tokens a month, GPT-5.5 costs $550 at published rates and GPT-5.4 mini costs $83 — $5,610 a year apart for the same volume. What you can actually move depends on how much of your traffic is routine, which is a measurement rather than a guess.
Are these OpenAI API prices current?
They were last checked against OpenAI API pricing (official) on 2026-07-22. Every price on this page carries that date and a link to its source, and a scheduled check fails our build when any figure goes more than 30 days unverified. Vendors do change pricing between checks — the source link is there so you can confirm before you sign.
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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