Bid is the price at which buyers offer to buy currencies from the sellers. Bid is the price at which sellers offer to sell currencies to buyers. For example EURUSD is being quoted at 1.29752/1.29760. The bid is the left of first of the two quotes (1.29752). This is the conversion rate when you sell EUR and buy USD. The ask is the second of the two quotes. This is the conversion rate when you buy EUR and you sell USD.