For a richly aromatic black tea, use 2.5 g of tea (loose-leaf or powder) per 150 ml of hot water. This ratio also applies to spiced tea blends, as long as tea makes up at least 50% of the mixture.
Measuring black tea: finding your balance between flavour and bitterness
By the traditional method, tea is prepared as an infusion. Place your tea leaves in a strainer inside a warmed teapot, then pour hot water over them. For black tea, the recommended ratio is 2.5 grams per 150 ml of water, which is roughly half a teaspoon of tea.
Those who prefer convenience often reach for tea bags, which are pre-measured for a standard cup. Water temperature still matters, however. Allow the tea to steep for 2 to 7 minutes to achieve a full, aromatic infusion.
How steeping time shapes the flavour of your tea
The amount of tea you use affects both the strength of the brew and its caffeine content. A longer steep will also deepen the bitterness of the cup. That said, the colour and aroma of a black tea are shaped more by its origin and quality than by the quantity used.