FREE COST TOOL • OPENAI API PRICING
OpenAI API Token
Cost Calculator
Estimate monthly OpenAI API text-token cost from requests, total input, the cached share of input, output, and retries. Compare GPT-5.6 Sol, Terra, and Luna using official public rates checked July 24, 2026.
OPENAI API WORKLOAD
Example estimate—not a charge. This free page has no API key or billing connection and cannot call the API, add credit, subscribe, or charge you.
Cached input is part of total input, not extra input. The calculator charges 0 cached and 1,200 uncached input tokens per request, so it never double-counts the same input.
$0.015 per effective request · 1,000 requests including retries
$3 uncached + $0 cached · 1.2M / 0 tokens
800K output tokens at $15 per 1M
Checked July 24, 2026: GPT-5.6 Terra uses $2.5 input, $0.25 cached input, and $15 output per 1M text tokens. Standard short-context text-token estimate only.
SAME WORKLOAD, THREE MODELS
Compare the current presets.
| Model | Input / cached / output | Monthly estimate | Per request |
|---|---|---|---|
| GPT-5.6 Luna | $1 / $0.1 / $6 per 1M | $6 | $0.006 |
| GPT-5.6 Terra | $2.5 / $0.25 / $15 per 1M | $15 | $0.015 |
| GPT-5.6 Sol | $5 / $0.5 / $30 per 1M | $30 | $0.03 |
How to estimate OpenAI API cost
Start with representative production logs or a small non-billable planning sample. Enter total input tokens per request, then identify how many of those input tokens actually qualify for cached-input billing. Add average output tokens, monthly requests, and a retry allowance. The calculator applies each token class once and keeps the result separate from ChatGPT subscription pricing.
READ BEFORE BUDGETING
What this estimate excludes.
- Cache writes, Batch, Flex, Priority processing, and long-context price bands.
- Web search and other tools, storage, containers, audio, images, and video.
- Taxes, currency conversion, credits, negotiated rates, and future price changes.
- ChatGPT Plus or other consumer subscriptions, which are billed separately from the API.
OPENAI API COST FAQ
Questions people ask before using the API.
How is OpenAI API token cost calculated?
Multiply monthly uncached input, cached input, and output tokens by their separate per-million-token rates, then add the three results. This calculator also lets you include expected retries in the monthly request volume.
What is cached input in OpenAI API pricing?
Cached input is the reusable part of a prompt that qualifies for the model's published cached-input rate. In this calculator it is a subset of total input tokens, not an additional token volume, so the same input is never charged twice.
Does ChatGPT Plus include OpenAI API usage?
No. ChatGPT subscriptions and OpenAI API billing are separate purchase routes. Use the linked ChatGPT Plus versus OpenAI API calculator if you are still deciding which route fits your work.
Can this calculator charge my OpenAI account?
No. It runs locally in your browser, does not use an API key, and cannot add credit, start a subscription, call the API, or charge an account. The displayed amount is an editable estimate only.
What OpenAI API charges are excluded?
This calculator covers standard short-context text-token processing only. Cache writes, Batch, Flex, Priority processing, long-context price bands, tools, storage, audio, images, taxes, negotiated rates, and other product charges are excluded.
Independent planning tool; not affiliated with OpenAI. Rates checked July 24, 2026. Standard short-context text-token estimate only. Cache writes, Batch, Flex, Priority processing, long-context pricing, tools, storage, audio, images, taxes, negotiated pricing, and other charges are excluded. Verify the linked official documentation before purchasing or launching a workload.