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The Instruments

Diamond Price Calculator

An indicative range, read from carat weight and the four Cs.

The short answer

In September 2026 a 1 carat natural round diamond graded G–H VS2 with an excellent cut and a GIA report sells for about $4,000–6,000, and a 2 carat for about $22,000–28,000. Better grades raise that quickly — a 1 carat G VS1 reads about $5,000–7,100 here. Sold privately, natural diamond jewelry brings 30–50% of retail; lab-grown stones cost 75–90% less new and resell for little.

Figures reviewed September 2026

Carat
Shape
Cut
Color
Clarity

Tap the i beside any factor to see what it means.

Indicative value

$5,000$7,100

1.00 ct · Round · Excellent cut · G · VS1

Approximate retail, USD

An indicative range, not a formal appraisal.

What moves the figure

Weight is only the beginning

LOWHIGH
01Cut
02Colour
03Clarity
04Carat
Field notes

How to price a diamond, and what this calculator is doing

Every diamond price starts from a price per carat, not a price. A dealer looks up the going rate for the weight, shape and grade combination in front of them, multiplies it by the carat weight, then adjusts for the things a report cannot show: how the stone actually performs in light, whether the certificate comes from a laboratory the trade respects, and how quickly the seller wants their money.

This calculator does the same arithmetic in the open. It anchors to a one-carat round brilliant, G color, VS1 clarity, excellent cut, then scales that anchor by weight, shape and the four Cs. The result is a range, because a single figure would be a lie: two stones with identical grading reports routinely trade ten to twenty percent apart.

Why price per carat jumps at the round numbers

Diamond prices do not rise smoothly with weight. They step. A 0.99 carat stone and a 1.01 carat stone are indistinguishable on a hand, but the 1.01 can cost twenty to thirty percent more per carat, because the whole market shops at 1.00, 1.50 and 2.00. The same cliff appears at every magic weight.

That is also where the value is. A stone just under a threshold — 0.90, 1.40, 1.90 — is the cheapest way to buy size, and nobody looking at your hand will ever know.

What moves the number most

In rough order of effect on a US retail price:

  • Carat weight, which drives price faster than linearly because large rough is rare.
  • Cut quality, the only C that decides how bright the stone looks. A poorly cut D flawless can look duller than a well cut H VS2.
  • Color and clarity, which matter to the price sheet far more than they matter to the eye once you are inside the near-colorless and eye-clean ranges.
  • The laboratory on the report. GIA and AGS grading is treated as the benchmark; other labs are commonly discounted because their grades run softer.
  • Where you are buying. Mall retail, independent jeweler, online inventory and estate sale can be three different prices for the same stone.

Retail, market and resale are three different numbers

The figure here is an approximate retail range: what a comparable stone would be offered at today. It is not what you would be paid if you sold. Expect a private sale to bring roughly thirty to fifty percent of retail, and a dealer's cash offer twenty to thirty-five percent. The insurance instrument works those numbers out in detail.

The arithmetic, in the open

The calculator starts from a price per carat for a one-carat round, G color, VS1 clarity, then multiplies by a factor for the weight band, one for each graded C and one for the shape, and finally by the carat weight itself. The range either side of the result is plus or minus eighteen percent, because identical reports trade that far apart in practice.

Both tables below are computed from the calculator's own figures at build time, so they always agree with the reading above.

Indicative retail by carat weight — round, G, VS1, excellent cut
Carat weightIndicative retail rangePrice per carat at the mid figure
0.50 ct$1,300 – $1,900$3,300
0.75 ct$2,200 – $3,200$3,600
1.00 ct$5,000 – $7,100$6,100
1.50 ct$11,900 – $17,100$9,700
2.00 ct$23,800 – $34,300$14,500
3.00 ct$62,500 – $90,000$25,400

From the calculator above, calibrated in September 2026 to published prices for GIA-graded natural rounds. A private sale brings roughly 30–50% of these figures.

How the calculator builds a diamond price
InputFactor appliedWhy it moves
Anchor$5,500 per caratA 1.00ct round, G color, VS1 clarity, before the cut adjustment
Weight band (price per carat)Under 0.50 ct ×0.42 · 0.50 – 0.69 ct ×0.54 · 0.70 – 0.89 ct ×0.59 · 0.90 – 0.99 ct ×0.78 · 1.00 – 1.49 ct ×1.00 · 1.50 – 1.99 ct ×1.60 · 2.00 – 2.99 ct ×2.40 · 3.00 – 3.99 ct ×4.20 · 4.00 ct and above ×5.30Large rough is rarer, so price per carat steps up at the round weights
ColorD ×1.35 · E ×1.28 · F ×1.20 · G ×1.00 · H ×0.88 · I ×0.78 · J ×0.66 · K ×0.52Each step toward colorless is scarcer
ClarityFL ×1.60 · IF ×1.40 · VVS1 ×1.28 · VVS2 ×1.20 · VS1 ×1.00 · VS2 ×0.92 · SI1 ×0.78 · SI2 ×0.62 · I1 ×0.40Priced on the report far more than it is seen by eye
CutExcellent ×1.10 · Very Good ×1.00 · Good ×0.86 · Fair ×0.70The only C that decides how bright the stone looks
ShapeRound ×1.00 · Oval ×0.86 · Cushion ×0.84 · Princess ×0.82 · Emerald ×0.80 · Pear ×0.84Rounds waste the most rough in cutting
Range×0.82 to ×1.18 around the resultIdentical reports routinely trade 10–20% apart

Indicative US retail. Price = anchor × weight band × color × clarity × cut × shape × carat weight.

Questions we are asked

What is my diamond worth?
Enter the carat weight, shape and the three graded Cs above for an indicative retail range. If you are asking because you want to sell, the honest answer is lower: private buyers typically pay 30 to 50 percent of retail and dealers 20 to 35 percent, whatever the appraisal says.
How much does a 1 carat diamond cost?
In September 2026 a 1 carat round with a GIA report spans roughly $2,500 to $13,000 depending on its grades, and about $4,000–6,000 for G–H color, VS2 clarity and an excellent cut. A lab-grown equivalent costs about $800–1,500.
Is a diamond appraisal the same as its value?
No. Most appraisals are written as retail replacement value for insurance purposes, and are often above what the piece would sell for. They exist to settle a claim, not to price a sale.
Does a GIA certificate increase a diamond's price?
It does, in practice. A report from GIA or AGS gives a buyer confidence in the grades, so certified stones command more than uncertified ones and more than stones graded by softer laboratories.
The Lovenhall RegistryBeyond the Estimate

Read the stone itself

This calculator works from what you type. The instrument works from a photograph — the four Cs estimated, and a range with them.

Free on iPhone, iPad & Android. An estimate, never an appraisal.
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