Methodology and Limitations

When a location is searched for the first time, its name is matched to a real place using the OpenStreetMap place directory. The cost figures themselves are then written by a large language model (currently Google Gemini) from its general training knowledge, following fixed instructions: monthly ranges in USD for one adult, in six categories.

Category estimates are not fetched from price sources. The site does not query government statistics, rental listings or price indices, and generated figures are not checked by a person. Treat them as model estimates that can be wrong, sometimes by a wide margin.

The site shows four kinds of numbers, and labels them separately:

• Model estimates: every category range and the comfortable-living figure. Dated by when they were generated.
• Published tariff benchmarks: for a few cities (currently Lisbon, Barcelona and London) the official price of specific monthly transit passes, with publisher, link, scope, native currency and the date the page was checked by hand. They cover only that product; they do not make the city's rent, food or other categories verified.
• Your own amounts: anything typed into the budget tool, or a pass applied with "Use this pass in my budget" (which replaces the transport amount). Kept only in your browser tab.
• Exchange rates: ECB reference rates, dated by the ECB reference date (see below).

Location identity (name, country, region) comes from OpenStreetMap; cost figures do not.

• Categories: rent (1-bedroom), food, transport, utilities, healthcare, and entertainment/leisure, each as a low–high monthly range.
• Total excluding rent = sum of the low ends of every non-rent category, to the sum of the high ends.
• Total including rent = the above plus the rent range.
• Adding all low ends (or all high ends) together gives the widest plausible span; most real budgets land in between.
• Comparisons use the same excluding-rent totals and range midpoints. "X% cheaper" is measured against the more expensive place ($100 vs $200 is 50% cheaper).
• Dining out: estimates generated before this was clarified may count some restaurant spending in both food and entertainment, which can overstate totals slightly.
• Find by Budget uses the same totals (with or without rent, your choice) and lists places whose range overlaps your budget range.
• Comfortable living is a separate model estimate of monthly spending (including rent). It excludes income tax and savings, and is not derived from the category sums.
• Summaries, FAQs and comparison "Why?" notes are model-generated text. FAQ answers quoting dollar figures are replaced by one calculated from the displayed totals.

Model estimates are stored in USD. Conversions use a snapshot of the European Central Bank euro reference rates dated 2026-09-29, refreshed when the site is rebuilt (if the ECB feed is unreachable the previous snapshot and its date are kept). ECB publishes rates against the euro, so each per-dollar rate is the euro rate for that currency divided by the euro rate for USD. These are reference rates, not live or bank/card transaction rates: 1 USD = 0.8807 EUR, 1 USD = 0.7549 GBP, 1 USD = 1.4180 CAD, 1 USD = 1.4277 AUD, 1 USD = 157.12 JPY, 1 USD = 95.99 INR. Converted amounts are rounded to whole units.

Each location page shows when its estimate was generated. That is the date the text was produced, not the date of any underlying prices; the model's knowledge may be older than that date.

Published tariff benchmarks show the date they were checked, and an effective date when the publisher gives one. Exchange rates show the ECB reference date. None of these dates is the date a page was built.

Stored estimates are reused for roughly two months. After that, a new estimate is generated the next time someone opens the page. There is no scheduled refresh.