Full Answer

Currency switcher plugins allow WooCommerce stores to show prices in the visitor's local currency. When a customer in Japan views a store with USD as its base currency, the plugin converts displayed prices to JPY. This improves the shopping experience but introduces a data integrity problem for analytics and conversion tracking.

The base currency is what WooCommerce uses internally for all calculations, inventory, and order records. It is the store's single source of truth for revenue. The display currency is the converted value shown in the storefront — calculated by the currency switcher using an exchange rate that may update daily, hourly, or not at all depending on configuration. The settlement currency is what the payment processor actually charges the customer and deposits into the merchant account, which may differ from both the base and display currencies depending on the gateway's multi-currency handling.

The tracking problem occurs because most WooCommerce analytics integrations — GA4 tags, Facebook Pixel events, Google Ads conversion tags — fire on the frontend and capture the display currency value. If a customer buys a $100 USD product while viewing the store in EUR at a 0.92 rate, the tracking event reports EUR 92 rather than USD 100. GA4 receives EUR 92, Google Ads receives EUR 92, and Facebook receives EUR 92 — while WooCommerce's order record shows USD 100.

The revenue discrepancy compounds across orders, currencies, and time as exchange rates fluctuate. Monthly revenue in GA4 may show a different total than WooCommerce's order export because each order was tracked at a different exchange rate on a different day. Server-side tracking implementations that read the order value from WooCommerce's base currency field rather than the frontend display value eliminate this corruption at the source.