AI chat guide
How We Grade AI Chat Sites: Criteria, Weights and Sources
Checked on Oct 28, 2026
This page explains how we grade AI chat sites: which five criteria feed the Grade, how much each one weighs and where the facts come from. The Grade is a number from 0 to 10 shown next to each service, and the site calculates it automatically from its registry of facts. The method applies since 28 Oct 2026.
Chat IA +18 runs under the domain ChatIA18.com and is for adults only. The Grade does not rest on personal use of any service, only on facts that the services publish themselves.
What the Grade measures
The Grade covers 10 services, and price comparisons are made among these 10 only. Each criterion uses one rule and one kind of source.
- Price (30%). We take the lowest monthly price of the web subscription in USD and divide the cheapest such price among the 10 services by the service's own price. The cheapest service gets 10, a service twice as expensive gets 5, and the values in between are proportional.
- Language (20%). If the service publishes a language list that includes a Portuguese interface, it gets 10. If not, it gets 0. If it publishes no list, the criterion is unknown. This says nothing about how good the chat replies are in Portuguese.
- Free plan (20%). No free plan means 0. A free plan gives 4, plus up to 4 more for free messages (full at 100 or more) and up to 2 more for free images (full at 10 or more), with a maximum of 10. If the free limits are not published, the free plan alone counts as 4.
- Payment options (15%). We count payment methods other than a card, such as PayPal, Pix, crypto, Apple Pay or Google Pay, bank transfer or the app store. None gives 0, one gives 3.3, two give 6.7, and three or more give 10.
- Cancelling (15%). We average what is known of two items. The first is whether you can cancel yourself on the website or through the app store (yes is 1, only via support or e-mail is 0). The second is the number of steps (up to 3 is 1, 4 is 0.5, 5 or more is 0). The possible results are 0, 2.5, 5, 7.5 and 10.
Some things are not part of the Grade: impressions of chat quality, user reviews, third-party ratings and commissions. Legal obligations, such as account deletion, company details, age checks or statutory refunds, are left out too, since we do not count them as advantages.
Weights, scale and the final number
The scale runs from 0 to 10 in steps of 0.1. Every criterion and the total are shown on this scale and rounded half up to the step. The five weights add up to 100%.
To get the final Grade, the site multiplies each known criterion's value by its weight, adds the results and divides by the total weight of the criteria that have data. A criterion without data is simply left out rather than scored as zero, so the other criteria carry a larger share. A service with fewer than 3 known criteria gets no Grade.
Commissions do not change the Grade. They can influence the order of lists on the site, as explained on how the site earns money.
The table below summarises the method, with the weight, source, step and treatment of missing data for each criterion.
0–10, step 0.1 · Minimum: 3 criteria
| Criterion | What counts | Weight | Source | Step | Missing data |
|---|---|---|---|---|---|
| Price | We divide the cheapest monthly price among this site's services by the service's own lowest monthly price: the cheapest gets full marks, pricier ones proportionally less. | 30% | Official price pages | 0.1 | Left out |
| Language | Whether the service offers its interface in Portuguese: yes earns the maximum, no earns zero. | 20% | Official website | 0 / 10 | Left out |
| Free plan | No free plan means zero. A free plan earns 40% of this part, plus up to 40% for free messages (100 or more) and up to 20% for free images (10 or more). | 20% | Official plan pages | 0.1 | Left out |
| Payment options | How many ways to pay besides a card the service accepts, such as Pix, digital wallets or crypto. Three or more earn the maximum. | 15% | Checkout page | 0 / 3.3 / 6.7 / 10 | Left out |
| Cancelling | Whether you can cancel on your own on the website or in the app store, and in how many steps: up to 3 earns full marks, 4 earns half, 5 or more earns nothing. We average whichever is known. | 15% | Help centre | 0 / 2.5 / 5 / 7.5 / 10 | Left out |
Where prices and facts come from
Prices come from each service's official pricing pages, and other facts come from its help centre, terms, privacy policy and app stores. Each fact is recorded in our registry with a check date. All facts were last checked on 22 Oct 2026, the same date for every service so far.
Prices are in US dollars. The local amounts marked with "≈" are our estimates: the USD amount multiplied by the ECB reference rate of 22 Oct 2026, without VAT for Brazil. Your bank may add IOF on a purchase in foreign currency, so the final charge can differ. Always check automatic renewal and taxes on the checkout page before paying.
Recalculation and updates
When a fact in the registry changes, the Grade is recalculated with it. We do not promise a fixed recheck schedule, but each service page shows its check date, so you can see how fresh the data is. If we add our own checks of the services later, this page will explain how they work.
On privacy: by default the site uses no analytics or tracking pixels. It sets a session cookie for the 18+ confirmation and a consent cookie kept for up to 365 days. More detail is on the privacy page. The age confirmation is self-declaration for now.
To report an error or content, or to ask about the method, use the form on the contact page. Reports are answered. The home page lists the services the Grade covers.