Data sources
We aggregate prices from four classes of sources, each weighted differently in our pipeline:
- Crowdsourced cost-of-living databases - primarily Numbeo, the largest open dataset of consumer-price submissions. We treat each submission as a single signal; outliers and items with insufficient sample size are excluded.
- Public retailer and chain menus - public price lists from supermarkets, restaurant chains and franchise menus (McDonald's, KFC, Burger King, Pizza Hut and similar). Where a chain operates in multiple countries, we capture per-country pricing because items, sizes and taxes differ.
- Public economic indicators - currency exchange rates from public FX feeds, VAT and sales-tax rates from national tax authorities, average wages from public statistical offices.
- Editorial corrections - manual price updates submitted by our editorial team after on-the-ground verification (typically when a country page changes substantially or when a chain re-prices its menu).
How a single price gets to your screen
- Ingestion. Raw values are pulled from each source on a regular schedule. Crowdsourced data is refreshed continuously; public menus and FX rates daily; statistical indicators monthly.
- Normalisation. Every value is converted into the local currency of the country it belongs to. We strip currency symbols, handle decimal-comma vs decimal-dot, and remove obvious data-entry errors (e.g. a beer at 0.001 EUR or 9 999 999 USD).
- Statistical filtering. For each country-product pair we compute the median of the last N submissions and drop everything outside roughly two standard deviations. Country-product pairs with fewer than five submissions are flagged as low-confidence and either hidden or shown with a notice.
- Cross-currency conversion. The local-currency median is converted to USD and EUR using current FX rates, so users browsing from any country can compare like with like.
- Editorial review. Country and city pages with substantial changes go through manual sanity checking before being re-published. Anything that looks suspicious (a sudden 5x change, a single outlier source pushing the median) is held for review.
- Publication. The final values appear on country, city, restaurant-chain and category pages. Each page carries a "last-updated" indicator showing when the data behind it was last regenerated.
What we don't do
- We don't accept paid inclusion. No retailer, restaurant or chain pays us to be listed, ranked higher or shown more favourably.
- We don't track prices in real time. Our values are aggregated medians refreshed on a schedule, not a live ticker. For real-time prices contact the retailer directly.
- We don't claim accuracy in the legal sense. Prices are signals, not commitments. Always verify before making a financial decision.
Data freshness
Each country and city page shows a "Prices last updated" date. That date refers to the last time the underlying dataset for that page was regenerated - not just the page render. Most country-level data is refreshed at least weekly; city-level data is refreshed continuously as new submissions arrive.
Reporting an issue
Spotted a price that looks wrong, a chain that recently re-priced its menu, or a city we got upside-down? Use the contact page and we will queue it for editorial review. Volume is high so we cannot reply individually, but every report is read.
Editorial standards
- All editorial content (country overviews, city descriptions, FAQ answers) is written or reviewed by the Wereld-Prijzen Editorial Team.
- Translations into 25 languages are produced by a mix of professional translators and machine translation with human post-edit. Languages with low traffic are reviewed less frequently than core languages.
- Affiliate or third-party content (where it exists) is clearly disclosed on the page where it appears.