USD/HKD is the exchange rate between the US dollar and the Hong Kong dollar, showing how many Hong Kong dollars one US dollar will buy. It is a minor pair, accounting for about 3.6% of the roughly $9.6 trillion that changes hands in the global forex market each day (BIS Triennial Survey, 2025), though its day-to-day movement is among the smallest of any traded pair.
The US dollar is the base currency and the Hong Kong dollar the quote currency, so a quote of 7.8000 means one US dollar is worth 7.8000 Hong Kong dollars. A rising price means the US dollar is strengthening against the Hong Kong dollar, a falling price the reverse. You trade USD/HKD as a forex CFD, taking a position on the price rather than holding Hong Kong dollars outright: go long or short depending on your view. Pips are at the fourth decimal place, and your profit or loss is the pips gained or lost times your position size, settled in Hong Kong dollars.
This pair barely moves, because the Hong Kong dollar is pegged to the US dollar inside a narrow 7.75 to 7.85 band under the Linked Exchange Rate System. The Hong Kong Monetary Authority defends that band by buying or selling dollars at the edges, so instead of trending the rate drifts between the two limits. The main thing that nudges it is the gap between US and Hong Kong interest rates, which can push the pair toward one side of the band before the peg pulls it back.
Say USD/HKD is trading at 7.8000 and you expect the US dollar to edge higher within the band, so you buy one standard lot (100,000 US dollars). Each pip is worth 10 Hong Kong dollars. Because the peg keeps moves small, a 20-pip rise to 7.8020 gives:
20 √ó HK$10 = HK$200 (about $26)
A 20-pip fall to 7.7980 would instead cost HK$200. The contract is worth $100,000, and at 30:1 leverage your margin is about $3,333, which magnifies both gain and loss.