What to know first
A subscription price is not comparable by number alone. Identify the purchase channel, plan, and billing period first, then check whether the quote is tax-inclusive, tax-exclusive, or unknown. A converted amount is a reference; the checkout total decides what you pay.
Start by defining the quote you are comparing
A web subscription, an App Store purchase, and API or enterprise usage are different purchase arrangements. They can use different currencies, tax treatment, billing periods, and available plans, so their displayed amounts should not be placed in one ranking without qualification.
AISub filters by purchase channel, plan, and billing period before calculating a reference price. The result compares recorded quotes; it does not establish that every account can buy the displayed plan.
| Your question | Confirm first |
|---|---|
| Comparing web subscriptions by region | The same plan, billing period, and tax basis |
| Comparing an App Store purchase | Storefront, in-app product name, and checkout amount |
| Estimating API or enterprise cost | The API rate card or enterprise agreement, not web subscription pricing |
Sources: AISub: Data sources and calculation notesOpenAI: ChatGPT pricing and plans
Align the plan and billing period before comparing amounts
Free, Go, Plus, Pro, Business, and Enterprise plans serve different users and include different features. Official pricing pages also separate individual, Business, and Enterprise offerings, so start with the plan name and purchase path.
A monthly amount and an annual amount are not directly comparable. When the annual period and total are confirmed, AISub shows a monthly reference equivalent. When the period or total cannot be confirmed, the original quote remains visible and is excluded from monthly rankings.
For Business and Business 5x, the monthly amount is shown as a per-seat monthly price. An annual amount is shown as the per-seat monthly equivalent when paid yearly. The annual reference amount is that monthly equivalent multiplied by 12; it does not mean the user is charged monthly.
| Page label | Meaning for comparison |
|---|---|
| Monthly | The amount charged each month; individual plans are generally per account |
| Annual | A yearly payment; the page may show a monthly reference equivalent |
| Per seat | The amount for one seat; the total depends on the number of seats |
| Period unconfirmed | Keep the original quote; do not infer a monthly or yearly total |
Sources: AISub: Data sources and calculation notesOpenAI: ChatGPT pricing and plans
Understand tax-inclusive, tax-exclusive, and unknown tax treatment
A useful price comparison states its tax basis. A tax-inclusive quote includes taxes explicitly shown by the source. A tax-exclusive quote excludes taxes; it does not mean the user is automatically entitled to tax exemption. Unknown means the source does not provide enough information to classify the quote.
When a region has both a tax-inclusive and a lower tax-exclusive quote, AISub uses the tax-exclusive amount as the lower reference and keeps the tax-inclusive amount as a comparison. When one amount is missing, AISub does not reverse-calculate it from a tax rate.
The checkout result determines the tax and final amount. The billing region, account eligibility, payment channel, and product tax rules can affect what is charged.
| Label | What it supports | What it does not support |
|---|---|---|
| Tax-inclusive | The quote includes taxes explicitly provided by the source | It does not guarantee the same checkout total for every account |
| Tax-exclusive | The quote excludes taxes and supports a pre-tax comparison | It does not prove that the user qualifies for tax exemption |
| Tax unknown | The source is not sufficient to classify the tax basis | It should not be treated as inclusive or exclusive |
Use exchange-rate conversions as references
Regional quotes often use different currencies. AISub uses one reference-rate snapshot to show amounts in the selected display currency and records the quote update time separately from the exchange-rate update time. The original amount stays visible for checkout verification.
A converted amount is not the final charge from a bank or payment platform. Card exchange rates, fees, payment-channel rules, and the checkout time can produce a different amount.
Reference amount = original amount ÷ source-currency rate × display-currency rate
Example: if USD 1 = CNY 7.20, a USD 20 quote has a CNY 144 reference amount
Why missing or stale data is not filled with an estimate
A region may not have a quote for a plan, billing period, or purchase channel. A conversion may also be unavailable because the required exchange rate is missing. AISub labels these cases as not provided or unavailable instead of filling the gap with a nearby region, a tax rate, or an assumed exchange rate.
If a regional refresh fails, the page may keep the last successful quote and show its update time. This preserves a traceable last record without presenting old data as a new collection.
- Missing quote: this does not prove that the plan is unavailable in the region; it means there is no usable record at the moment.
- Missing exchange rate: the reference amount cannot be calculated, but the original quote can still be reviewed.
- Older data: check both the quote update time and the exchange-rate update time before verifying the checkout page.
How rankings, monthly equivalents, and annual references work
Rankings use the reference amount adopted by the page and compare values before rounding. Quotes with different tax bases are not silently treated as the same kind of price; use the tax filter to inspect one basis at a time.
An annual plan's monthly reference equivalent helps display it beside a monthly plan. The annual reference amount equals the monthly equivalent multiplied by 12. It is a budgeting reference and does not change the actual annual billing period.
Annual monthly equivalent = annual total ÷ 12
Annual reference amount = annual monthly equivalent × 12
Use this checklist when a quote looks cheaper
The purpose of a comparison is to reduce misreading, not to promise that a region will be eligible or cheapest. Use the comparison result alongside the official checkout page for the final purchase decision.
- Confirm that the quote uses the same purchase channel, plan, and billing period as the comparison.
- Check whether it is tax-inclusive, tax-exclusive, or tax unknown.
- Read the original currency, reference rate, and both update times.
- For annual or per-seat plans, confirm the yearly total and seat count.
- Finally, confirm availability and the actual amount on the signed-in official checkout page.
Frequently asked questions
Is the price on the page the amount I will pay?
Not necessarily. The page provides regional comparison quotes. Your final amount depends on the purchase channel, billing region, account eligibility, taxes, payment method, and the official checkout result.
Does a tax-exclusive quote mean that I am tax-exempt?
No. It only means that the quote excludes taxes. Whether tax is due and how much applies depends on the billing region, product rules, and the checkout result.
Why can the same plan cost differently on the website and in the App Store?
They are different purchase channels and can use different local prices, tax treatment, and billing rules. Compare within one channel first, then verify the checkout amount for that channel.
How is an annual price converted to a monthly equivalent?
When the annual period and total are confirmed, the annual monthly reference equivalent equals the annual total divided by 12. It is for comparison display; the actual charge remains annual.
Why is a price or converted amount missing for a region?
The plan or billing period may not have a usable quote, or the exchange rate needed for conversion may be unavailable. The page does not fill the gap with a tax-based or guessed amount.
Can an exchange-rate change alter the original plan price?
No. It changes the reference amount in the selected display currency. The original quote and official checkout amount remain the source for payment, and a payment provider may apply its own rate or fee.
Official sources and review notes
Sources checked on October 18, 2026. Rates and eligibility rules can change; confirm the latest official guidance and your own agreement.
AISub prepared this guide from public OpenAI documentation, with an independent worked example and purchasing advice. AISub is an independent price index and is not affiliated with OpenAI.