Length and fit: where each inch sits, and what your skin has to say about it

Almost every returned necklace is the right chain in the wrong length. It is the one decision a photograph cannot help with, and it takes a minute and a piece of string to get right.

The skin section below is general information from a public health page, read on the date shown. It is not medical advice, and a rash that persists is a question for a clinician rather than for a jewellery site.

A necklace is one number you cannot fix later

Width can be judged from a photograph if the page prints millimetres. Metal is written on the page. Length is the only measurement that depends on the person wearing it, and the same 18 inch chain sits in three different places on three different necks.

So the table below counts our own catalogue rather than repeating a chart copied between jewellery sites.

The ladder, inch by inch

Working from the throat down on most adults: 14 to 16 inches closes at the base of the neck. Eighteen rests on the collarbone and 20 falls just below it. Twenty-two sits at the top of the sternum, and 24 and longer hang over a shirt rather than under it.

For a pendant, add two inches to the length you would choose for a plain chain. The pendant hangs from the lowest point of the chain, not from the clasp.

What this range actually holds

Length is not evenly stocked across the families, and the honest version of that is a count rather than a promise.

Where a family exists in several lengths, the product page lists them all and links straight across, so choosing a longer one takes a click rather than a search.

1mm Rose Gold over Sterling Silver Cable Chain 16 in

One body, several lengths: the page carries the whole ladder

$18.994.5 out of 5

The string trick, in one minute

• Take a shoelace or a piece of string and hold it at the back of your neck
• Let it fall where you want the chain to sit, with the collar you would actually wear
• Pinch the point at the front, take it off, and measure the loop flat against a ruler
• That number is your length. If it lands between two, buy the longer and add an extender

The extender is the reason this is a low-risk decision. Two inches of chain and a second clasp cost a few dollars and turn a 16 into an 18, and that is why they sit in the same department as the sets.

Width changes the answer

A fine chain and a heavy one at the same length look like different lengths on the body, because a heavier chain hangs deeper under its own weight and a fine one follows the neck.

As a rule of thumb, above about 3mm choose the length you measured. Below about 1.5mm consider going one step longer if you want the chain to sit away from the throat. The widths in this range run from 0.8 to 10 millimetres, and every page prints its own.

Hoops are measured across, not around

Hoop sizes are outer diameter, so a 15mm hoop is about the width of a fingernail and a 50mm hoop reaches the jaw on most faces. The number is not the circumference, which is where the surprise usually comes from.

Small hoops and huggies stay out of hair, scarves and phone screens. Large hoops move, catch light and get caught. Both are legitimate, and every page prints the diameter so you choose before the parcel arrives.

Hoops and huggies by diameter

Every pair states its outer diameter in millimetres on the page.

15mm Rose Gold over Sterling Silver Huggie Earrings, Style JP-RC31C

15mm · rose gold plated over sterling

$9.994.6 out of 5

5mm Rose Gold over Sterling Silver Hoop Earrings

5mm · rose gold plated over sterling

$14.994.6 out of 5

4mm Rose Gold over Sterling Silver Hoop Earrings

4mm · rose gold plated over sterling

$15.994.6 out of 5

15mm Gold over Sterling Silver Huggie Earrings

15mm · gold plated over sterling

$9.994.5 out of 5

All Jewlpire earrings

The sensitive-skin question, honestly

Reactions to jewellery are usually contact dermatitis, and the metal most often behind them is named plainly by the public health encyclopedia.

Two practical things follow. Nickel is common in alloys and in the layers beneath plating, so a piece can be gold on the surface and still meet skin with something else once the plating wears at a rub point. And because the reaction usually appears a day or two after wearing, the piece that caused it is rarely the one you have on when you notice.

Where a maker states nickel-free we print that as their statement rather than as ours, and the metal guide explains why hypoallergenic has no legal definition here. If a piece marks your skin, stop wearing it. That is the only advice this site is qualified to give.

Layering without tangling

Layered chains tangle when they are the same length and the same weight. Two inches of difference is the minimum that reads as deliberate, and four is easier to live with.

Mixing link types helps as much as mixing lengths: a flat snake chain and a round cable chain slide past each other, where two ropes of the same width will braid themselves together by lunchtime.

Where our table is empty

Of the 345 entries on this site, 321 publish a width, 277 publish a length and 254 name the clasp. The rest do not, and we leave those rows empty rather than filling them with a plausible number.

If a measurement matters to your decision and the page has none, write to us. We would rather answer one message than publish a number we cannot stand behind.