The lines a necklace creates can be used to visually, highlight, alter, or mask body features. In other words, your body's structure will determine which necklace looks best on you. Below are considerations you should take into account when selecting a necklace.
Choosing a necklace that fits your body and facial features
Your face

Face shapes can be categorized as oval, long (rectangular), round, or heart-shaped.
Heart-shaped
Shorter 12”-16” necklace lengths work best with a heart-shaped face. Chokers and collars are especially effective since they create an illusion of a broader chin.
Round
Longer 26”-36” necklace lengths help elongate the look of a round face. V-shaped and Y-shaped necklaces work especially well. Avoid chokers, collar necklaces, bib necklaces, and other short-length necklaces that will make an already-round face appear even rounder.
Long (rectangular)
A shorter 12”-16” necklace can help broaden and soften the appearance of a long, narrow face.
Oval
Oval faces can wear any necklace length with no impact to appearance.
Your figure
Mid-size
20”-22” necklaces help accentuate the bust line. Women with smaller bust may opt for a long, thin chain or layered chain necklaces.
Full-figured body
Full-figured body types should lean toward necklaces that sit higher (i.e. shorter necklace lengths).
Wide necks/broad shoulders
Women with wide necks or broad shoulders should avoid chokers and other extremely short necklaces. Such necklaces will make the neck look even wider.
Long and short necks
Women with long necks look best with choker type necklaces. Conversely, chokers can make a short neck look stubby.
Your height
Short

Women under 5’5” should work with necklaces 16”-20” in length. These help elongate the neckline which adds the appearance of taller height. In contrast, a long necklace overwhelms a shorter frame.
Tall
Those over 5’7” can wear any necklace length well but of course, longer lengths will better fit a taller frame.
Other considerations
If you have wrinkly neck, avoid tight fitting necklaces which draw attention to the area. Instead, opt for a longer necklace, preferably one with a pendant to direct the viewer’s eye away from the neck area.
How to match necklace lengths and styles with clothing necklines
In addition to body features, your dress or blouse's neckline should influence the style of necklace you wear.
14-inch necklaces
Worn tight around the neck, this necklace length works best with open-neck clothing such as
scoop necks, v-necks, and off-the-shoulder necklines.
16-inch necklaces
Choker style necklaces work with any neckline except of course
turtlenecks or other necklines that would hide the necklace.
18-inch necklaces
Princess style necklaces that sit on the collarbone look best with crew necklines and plunging necklines.
20-24-inch necklaces
The Matinee style necklace, which sits between the collarbone and the bust, look good with both business and
casual wear.
28–36-inch necklaces
Opera style necklaces are worn best with high-neckline clothing and evening wear.
36-52 inch necklaces
Long rope necklaces that are wrapped or fall just below the bust, work well with business and evening wear.