Read the checkout currency
Confirm the currency the retailer actually uses for the destination and do not rely only on a header selector.
DEEP DIVE · CURRENCY
A converted number needs a source and a time.
Retailer display currency, settlement currency and the shopper's card statement can differ. Currency conversion should make those layers visible rather than suggesting a guaranteed final exchange rate.
Store the original amount
Keep the retailer amount and ISO currency code before any conversion is calculated.
Name the rate source
Record the rate source, currency pair, observation time and rounding method instead of showing an unexplained conversion.
Label the estimate
A converted display is indicative unless the retailer guarantees settlement in that exact local amount.
WHERE DIFFERENCES APPEAR
The same basket can create several currency amounts.
A retailer may show SGD, MYR or PHP but settle the transaction in another currency. A payment provider may then apply its own rate or foreign-transaction fee.
Those card or wallet terms belong to the shopper's payment relationship and may not be available to a public comparison service. Unknown payment-provider charges should remain outside the retailer-observed checkout total.
Exchange rates can change between the comparison, checkout and card posting dates. Keep the price and rate timestamps together so the estimate is not presented as a guaranteed settlement amount.
Original amount
Always retain the retailer amount and currency alongside any local estimate.
Rate source
Record provider, rate pair, timestamp and rounding instead of an unexplained conversion.
Checkout currency
Distinguish a display selector from the currency actually charged.
Issuer fees
Do not assume the shopper's bank or wallet adds no fee.
DISPLAY RULE
Show certainty at the level the evidence supports.
When a retailer provides an exact checkout price in SGD, MYR or PHP, show that retailer amount directly. When conversion is necessary, clearly mark the converted value as an estimate with its source time.
A comparison should never mix currencies in a ranking or hide the conversion basis in fine print.