Pricing model used by this calculator
This page is designed for people searching for a GPT-5.5 API pricing calculator because they already have a rough workload in mind: coding agents, document analysis, customer support routing, batch enrichment, or long-context repository work. The calculator does not guess your usage from a plan name. It asks for the variables that actually drive token billing: request count, input size, cached input share, output size, model, and processing mode.
Prices were checked on May 20, 2026 against OpenAI's API pricing and model documentation. GPT-5.5 is listed with a 1,050,000 token context window and 128,000 max output tokens. GPT-5.5 Pro uses the same published context and max output limits but costs more because it spends more compute on difficult requests. The calculator keeps both choices visible because many real workloads should route only a small fraction of traffic to the Pro model.
| Model |
Input / 1M |
Cached input / 1M |
Output / 1M |
Best fit |
| GPT-5.5 |
$5.00 |
$0.50 |
$30.00 |
Hard coding, agent workflows, long professional tasks. |
| GPT-5.5 Pro |
$30.00 |
No cached discount |
$180.00 |
Small volume of the hardest tasks where accuracy matters more than latency or cost. |
| GPT-5.4 |
$2.50 |
$0.25 |
$15.00 |
Cost-controlled coding and professional work. |
| GPT-5.4 mini |
$0.75 |
$0.075 |
$4.50 |
High-volume simpler tasks, classification, extraction, and routing. |
How to estimate your token inputs
For a coding agent, input tokens are usually the dominant cost driver because the same repository context is sent repeatedly. A small bug fix may only need a few thousand tokens. A multi-file feature that includes instructions, file excerpts, test output, and a review loop can easily reach tens of thousands of input tokens per turn. If the agent keeps a long conversation open, later turns carry earlier messages too, so the average input size rises during the session.
Use conservative assumptions before production launch. For a first estimate, separate your workload into three groups: simple requests that can use GPT-5.4 mini, regular requests that need GPT-5.4 or GPT-5.5, and rare hard requests that justify GPT-5.5 Pro. Then run the calculator for each group and add the totals. This is more accurate than pricing every request as if it used the most expensive model.
Batch, Flex, Priority, and regional processing
Standard processing is the baseline. Batch is for asynchronous work with a 24-hour completion window and lower cost. Flex also targets lower-priority work and may be slower or temporarily unavailable, while Priority is for user-facing latency-sensitive traffic. The calculator models Batch and Flex at half the standard token rate and Priority at a 2.5x multiplier. Regional processing is modeled as a 10% uplift for the supported GPT-5.5 family models.
Long-context surcharge and cache behavior
OpenAI's GPT-5.5 model documentation states that prompts above 272K input tokens are priced with a 2x input and 1.5x output surcharge for the full session for standard, batch, and flex. The calculator applies that threshold when the average input tokens per request cross 272,000. If you are close to the threshold, test whether summarizing old context, using file search, or splitting the job into smaller requests keeps quality high enough without crossing into long-context pricing.
Prompt caching matters most when a stable system prompt, schema, project guide, or reference document repeats across many requests. A higher cache share can reduce input cost sharply for GPT-5.5 and GPT-5.4. It does not help the output side, and the calculator disables cached input for GPT-5.5 Pro because the model page does not list a cached input discount for Pro.
FAQ
Why is my GPT-5.5 estimate much higher than a simple request count?
Request count alone is not enough. A workload with 10,000 short prompts and a workload with 10,000 repository-sized prompts have completely different costs. Input tokens, output tokens, cache share, and long-context thresholds drive the final number.
Should I use GPT-5.5 Pro for every coding-agent request?
Usually no. GPT-5.5 Pro is useful for a small set of hard planning, debugging, and architecture tasks. Routine edits, extraction, and review loops should be routed to cheaper models first, then escalated when the result fails.
Is the estimate a guaranteed bill?
No. It is a planning estimate based on public token prices and your assumptions. Actual billing can differ because of tool calls, retries, image inputs, provider-side changes, and differences between measured and assumed tokens.