SUBLENS / METHODOLOGY

How we compare prices.

SubLens compares the same AI subscription and billing period across verified local offers. Each record keeps its original currency, source and verification date.

Regional coverage

We collect each published Google regional subscription page separately and check its selected country, plan, currency and billing period. Missing or malformed prices do not replace the last successful observation. Regions without a supported reference exchange rate still show their original price and are excluded from currency-converted rankings.

Website and iOS purchase channels

Website offers and Apple App Store listings are collected and shown separately. App Store evidence is bound to the country storefront, official app and developer, currency and exact plan label. Claude Pro and Max subscriptions include Claude Code. ChatGPT store listings lack item-level billing periods and sometimes show multiple prices under one name; all distinct prices remain visible with the period marked unspecified, outside monthly or yearly rankings. A published store listing does not guarantee eligibility or that new subscriptions are available.

What “cheapest” means

The lowest price is the lowest among the verified local quotes in our dataset, using unrounded reference exchange rates. It is not a claim about every country in the world. Taxes are not normalized. Tied markets are marked as joint lowest.

Local offers and reference prices

Only an explicitly regional official offer appears on the price map. Countryless official USD reference prices are shown separately and are never copied into local markets. A blank country means we have no verified local quote, not that the service is unavailable.

Billing, currencies and taxes

Monthly and yearly offers are separate. Annual offers show the actual upfront charge, with a monthly equivalent for context. We never invent annual offers from monthly prices. FX is an estimate, not a card settlement rate. Unknown taxes remain unknown. Trials and introductory promotions are excluded.

Verification and freshness

Official price and ECB exchange-rate checks run every four hours. Each quote keeps its last successful verification date. Failed requests, ambiguous tiers, unexpected currencies and large changes retain the previous quote and appear in the source status. This is a periodically checked reference, not a live checkout. Regional availability lists are reviewed separately and retain their own dates.

Official price sources

Map data: Natural Earth, public domain