In MetaTrader terminals, the minimum trade amount is determined by the margin required to open a trade. It depends on next factors:

For several instruments, the lowest margin requirement is just 1 USD. For example, to open a trade for such instruments as EURUSD, GBPUSD, AUDUSD, NZDUSD only 1 USD margin is required. You can read about how margin is calculated in this article.

You can also check the minimum trading amounts for each instrument on the Specifications page.

Please note: the company reserves the right to change trading conditions — including the minimum trade amount — at any time and at its sole discretion.