Tennis Bracelet Size Guide: A 5 Carat Line Is 62 Stones of 2.8 mm
Length is only the first number. Carat weight sets the size of every stone, the size sets the price per carat, and the clasp decides whether it stays on. Here is each one, with the arithmetic.
The author is the founder of Draco Diamond, which sells lab grown diamond tennis bracelets. Fit and care guidance comes from Jewelers Mutual and GIA; stone sizes from Stuller's chart. Prices are Draco's own, in Canadian dollars. Read October 18, 2026.
Most tennis bracelets are 7 inches, but the right length is your wrist plus a little
A tennis bracelet should sit close without pinching. Seven inches is the standard length, but the right length is your wrist measurement plus a small allowance.
Jewelers Mutual puts that allowance at a quarter to half an inch for a snug fit, and three quarters of an inch to an inch for a comfortable one.1
A tennis bracelet should leave room for one finger. Women's bracelets average 6 to 8 inches, so 7 is a middle, not a rule.2
Too loose is the bigger risk. A long line slides over the hand, knocks against desks and puts strain on the clasp. A snug line turns less and wears longer.
The name has a story. Chris Evert dates it to the 1978 US Open, when her bracelet broke and play stopped while she found it. Others date the story to 1987, and GIA says the name spread in the 1980s.783
How do you measure your wrist for a tennis bracelet?
Measure the wrist where the bracelet will sit, at the wrist bone, then add an allowance for the fit you want. A soft tape or a strip of paper is enough.
Wrap it around the wrist at the wrist bone, the broadest point, where a bracelet will actually sit.
If you used paper, mark the overlap and lay it on a ruler. Read it in inches or millimetres.
Add a quarter to half an inch for a close fit that stays put. A tennis bracelet should not slide far down the hand.
Add three quarters of an inch to an inch for a looser drape. Check that one finger fits under the line.
Seven inches is the standard length. Draco lets you choose the length at checkout, so order the size your wrist calls for.
Measure at the broadest part of the wrist, not the narrowest. The bracelet has to pass over the bone to sit in place.1
Fit by feel as well as by number. On the wrist, a well sized line should move about one to two centimetres without sliding toward the knuckles.9
Between two lengths, choose the shorter only if the clasp sits comfortably closed. A tennis bracelet that is slightly snug is safer than one that is slightly long.
Carat weight decides the size of every stone
Total carat weight tells you how big each stone is. The length is fixed at about 7 inches, so more carats means fewer, larger stones across the same span.
| Total weight | Stones on 7 inches | Each stone | Diameter |
|---|---|---|---|
| 1 ct | 127 to 148 | about 0.0075 ct | about 1.2 mm |
| 2 ct | 94 to 105 | about 0.02 ct | 1.7 mm |
| 3 ct | 74 to 85 | 0.035 to 0.04 ct | 2.1 to 2.2 mm |
| 5 ct | 57 to 64 | 0.08 to 0.09 ct | 2.8 to 2.9 mm |
| 7 ct | 51 to 54 | 0.13 to 0.14 ct | about 3.3 mm |
| 10 ct | 43 to 47 | 0.21 to 0.23 ct | 3.8 to 3.9 mm |
Each stone grows as the carat weight climbs
Approximate diameter of each round stone on a 7 inch line, by total carat weight. Millimetres.
Sources: round diameters by carat from Stuller's millimetre to carat chart; stone counts from 177.8 mm of length. Arithmetic: Draco Diamond.
The arithmetic starts with the length. Seven inches is 177.8 mm. Divide by the diameter of each stone, edge to edge, and you have the stone count.4
Check it against a real bracelet. Draco's 5 carat round line lists 62 stones. Five carats over 62 stones is about 0.081 carats each, or 2.8 mm on Stuller's chart.104
Sixty two stones of 2.8 mm span 173.6 mm, close to the full 177.8 mm. The small gap is the metal between the stones.
Light lines behave differently. One and two carat bracelets often use spaced or illusion settings, so their real stone counts can be lower than the table shows.
"A 5 carat round line is about 62 stones of 2.8 millimetres. Carat weight is really a decision about the size of every stone."
Garrett McMartin, Founder, Draco Diamond
Price per carat falls as the line gets heavier
Larger tennis bracelets cost more in total but less per carat. Across Draco's lines, the price per carat drops from about CAD 734 to about CAD 246 as the weight climbs.
| Bracelet | Total weight | From | Per carat |
|---|---|---|---|
| 3 ctw round | 3 ct | CAD 2,201 | CAD 734 |
| 5ct round brilliant | 5 ct | CAD 2,920 | CAD 584 |
| 7ctw princess, bezel set | 7 ct | CAD 3,496 | CAD 499 |
| 9ct emerald cut | 9 ct | CAD 4,205 | CAD 467 |
| 12ct mixed shape | 12 ct | CAD 5,760 | CAD 480 |
| 31.87ct emerald cut | 31.87 ct | CAD 7,825 | CAD 246 |
Price per carat falls as the line gets heavier
Draco starting prices in 10K gold divided by total carat weight. Canadian dollars per carat, October 2026.
Source: Draco Diamond catalogue, listed starting prices read October 18, 2026. Arithmetic: Draco Diamond.
The pattern is not a straight line. Shape and setting move the price: a three row pear line or a pear cluster costs differently from a single row of rounds.
The reason is labour. A light line has more, smaller stones to set per carat, and each stone takes the same care to set as a larger one.
So decide on the look first, then the budget. A 5 carat round line, at about CAD 584 a carat, is where many buyers land between presence and price.
Which tennis bracelet clasp is the most secure?
A box clasp with a safety catch. The box clasp holds the line closed, and a figure eight or side latch catches it if the box ever opens.
Box clasps are among the most durable and are used on heavy pieces. A figure eight safety works as an added seatbelt over the main clasp.5
Most tennis bracelets come with secure clasps, often with a safety latch.3
Draco ranks the options from most to least secure: a box clasp with a double safety, a box clasp with a figure eight, a lobster clasp with a safety chain, a lobster clasp alone, and a spring ring.9
Every Draco tennis bracelet uses a box clasp with a safety catch. Close both every time you put it on; the safety only works when it is fastened.
Prong, bezel or channel: the setting decides daily durability
How the stones are held matters as much as the clasp. Prongs show the most diamond, bezels protect it most, and channels sit flush with nothing to catch.
GIA describes the trade: prongs hold each stone with small claws, a bezel gives maximum protection for an active life, and a channel sits flush and snag free.3
Inspection keeps a line intact. Jewelers Mutual recommends a professional inspection twice a year, and every three to four months for fine pieces worn daily.6
Many owners never do it. In Jewelers Mutual's research, 39 percent of people who buy their own jewellery have never had it inspected.6
A jeweller checks the prongs, the links and the clasp. White gold may also need rhodium replating every few years to keep its colour.3
Draco makes tennis bracelets from 3 to 31.87 carats
Draco's tennis bracelets run from a 3 carat round line to a 31.87 carat emerald cut. Every one is lab grown, IGI certified and made in the length you choose.
Each line is offered in sterling silver, 10K to 18K gold and platinum. Every diamond is IGI certified, E to F colour and VS2 or better.
Every Draco piece carries 30 day returns, the Lifetime Authenticity Guarantee, free resizing, and free insured worldwide shipping to 25 markets, delivered duty paid with nothing collected at the door, and signature on delivery. Each piece ships with its IGI report, which you can verify free at IGI.org.
Returns run for 30 days from delivery, refunded to the original payment method. The buyer covers return shipping, and there is no restocking fee.
Browse the full range of lab grown diamond tennis bracelets, or see pieces under CAD 2,000.
Tennis bracelets, answered
What tennis bracelet size should I get?
Measure your wrist at its broadest point, then add a quarter to half an inch for a snug fit or three quarters of an inch to an inch for a relaxed fit. Seven inches is the standard length.
How many stones are in a 5 carat tennis bracelet?
About 57 to 64 round stones on a 7 inch line, each about 0.08 to 0.09 carats and 2.8 to 2.9 mm. Draco's 5 carat round bracelet lists 62.
What carat weight looks best for everyday wear?
It depends on the look you want. A 3 carat line has stones of about 2.1 mm and reads delicate; a 5 carat line, about 2.8 mm, reads clearly from across a room; 10 carats, about 3.8 mm, is a statement.
What is the most secure tennis bracelet clasp?
A box clasp with a safety catch, such as a figure eight or a double side latch. Box clasps are among the most durable, and the safety catch holds the line if the box opens.
How often should a tennis bracelet be checked?
Twice a year is the usual recommendation, and every three to four months for a fine bracelet worn every day. A jeweller checks the prongs, the links and the clasp.
Why is it called a tennis bracelet?
Chris Evert dates the name to the 1978 US Open, when her diamond line broke and play paused while she found it. Some accounts place it in 1987; GIA says the name spread in the 1980s.
References
- Jewelers Mutual, How to Measure Bracelet Size, September 29, 2025.
- Jewelers Mutual, How Should a Bracelet Fit?, April 20, 2026.
- GIA 4Cs, Tennis Bracelet Buying Guide, September 12, 2025.
- Stuller, Millimeter to Diamond Carat Weight Conversion Chart, 2025.
- Jewelers Mutual, Types of Jewelry Clasps, September 30, 2025.
- Jewelers Mutual, Professional jewelry inspections: what you need to know, September 29, 2025.
- JCK, Chris Evert and Monica Rich Kosann, August 18, 2022.
- Mental Floss, Why Is It Called a Tennis Bracelet?, June 28, 2024.
- Draco Diamond, Will a Tennis Bracelet Fall Off or Break? Safety Guide, July 15, 2026.
- Draco Diamond, 5ct Lab Grown Diamond Tennis Bracelet, Round Brilliant, accessed October 18, 2026.
Send us a comparable band and we will beat it almost every time
Same IGI certified specification, direct pricing, about half the listed price of Blue Nile and Brilliant Earth on bridal sets (55 percent below at the median, October 2026). Founder reviewed, no obligation, a quote back in one to three business days. Every Draco band is IGI certified, E to F colour, VS2 and better, with 30 day returns, a Lifetime Authenticity Guarantee, free resizing, free insured worldwide shipping to 25 markets, and signature on delivery.
