Tea grading is one of the most confusing and misunderstood subjects. To begin with, the grades of tea are not standardized worldwide and may vary according to origin. Also, a tea's grade does not necessarily indicate flavor or quality. Rather, tea flavor and quality are determined by many different factors including: the country of origin, the variety of the tea (usually named after the district where grown), the garden or estate, the elevation, the particular flush (picking) and the manufacturing after harvesting.

Black tea grading
Black tea is classified into four different categories: WHOLE LEAF, BROKEN LEAF, FANNINGS and DUST.

These prized leaves get graded as follows during the manufacturing process:

Whole leaf
FLOWERY ORANGE PEKOE (FOP)
Consists of fine, tender, young leaves rolled with a certain proportion of "tips".
These tips, being the very ends of the bud's leaves, constitute a guarantee of quality.

GOLDEN FLOWERY ORANGE PEKOE (GFOP)
FOP with "golden tips"(fine tips of the golden yellow bud's leaves)
TIPPY GOLDEN FLOWERY ORANGE PEKOE (TGFOP)
FOP with lots of "golden tips"
FINEST TIPPY GOLDEN FLOWERY ORANGE PEKOE (FTGFOP)
Exceptional quality FOP
SPECIAL FINEST TIPPY GOLDEN FLOWERY ORANGE PEKOE (SFTGFOP)
The very best FOP with a large proportion of leaves having golden "tips" of new leaf buds---a guarantee of very, very high quality
ORANGE PEKOE (OP)
Long, pointed leaves (larger than FOP) rolled lengthwise. Harvested when the terminal buds open into leaf. Orange Pekoe rarely contains "tips".”
PEKOE (P)
Shorter, less fine leaves without tips
FLOWERY PEKOE (FP)
Leaves specially rolled into ball shape.
PEKOE SOUCHONG (PS)
Shorter, coarser leaves.
SOUCHONG (S)
Large leaves rolled lengthwise. Often used for China smoked teas.
Experts also add 1 to denote top quality after a leaf designation;
For example:F.T.G.F.O.P.1, O.P.1, S 1 etc

Broken leaf
BROKEN ORANGE PEKOE (BOP)
GOLDEN BROKEN ORANGE PEKOE (GBOP)
FLOWERY BROKEN ORANGE PEKOE (FBOP)
TIPPY GOLDEN BROKEN ORANGE PEKOE (TGBOP)
GOLDEN FLOWERY BROKEN ORANGE PEKOE (GFBOP)
TIPPY GOLDEN FLOWERY BROKEN ORANGE PEKOE (TGFBOP)

Fannings
Made from smaller, flat pieces of broken orange pekoe and used to make quick-brewing, strongly flavored, robust teas with good color.
BROKEN ORANGE PEKOE FANNINGS (BOPF)

Dust
Tiny bits of broken leaf used to brew strong tea quickly, popular for tea bags.
BROKEN ORANGE PEKOE DUST (BOPD)
PEKOE DUST (PD)
RED DUST (RD)
SUPER RED DUST (SRD)
FINE DUST (FD)
SUPER FINE DUST (SFD)
GOLDEN DUST (GD)

Green Tea Grades
Each country grades their green teas differently and has their own set of complicated terminology. China greens are graded according to the age of the leaf and the finished style or shape of the leaf. China greens are produced in Gunpowder, Imperial, Young Hyson, Hyson, Twankay, Hyson Skin or Dust styles. Each of these style or shape categories possess several grades. For instance, Gunpowder is graded from Pinhead to Pea Leaf and further subdivided into extra, first, second, third, fourth, fifth, sixth, seventh, and Common Gunpowder.

Oolong Tea Grading
Grading for oolongs changes from Fanciest or Extra Fancy (best) to Common (worst). Unlike other grading systems, this one actually rates the quality of the drink you can get from the leaves. The top grades are Fanciest or Extra Fancy, Fancy, and Extra Choice (or Extra Fine).

Green and oolong teas are priced according to the variety of the tea, the province and estate where grown, and the flush or picking.