An open standard for diamond market intelligence

The diamond market, measured.

Caratlytics publishes the methodology, the grade scale and the price index behind the Caratlytics Score: a single 0 to 100 measure of a diamond's quality, value, certification and market position, computed for every certified stone we observe across more than one hundred retailers.

The evidence base
115+
retailers monitored
31.6M+
active listings
13.3M+
certified diamonds
5.5M+
diamonds matched across retailers

Figures refresh with each monthly index release. Counts are live platform totals at generation time.

The grade scale

Scores map to six consumer grades. The bands are fixed, published and identical everywhere the score appears.

A+
90 to 100
Exceptional
A
80 to 89
Excellent
B+
70 to 79
Very Good
B
60 to 69
Good
C
50 to 59
Average
D
0 to 49
Below Average

What the grades mean

Caratlytics Diamond Price Index

A monthly, openly licensed index of retail diamond prices: median USD per carat for natural and lab-grown diamonds, computed from a systematic sample of millions of listings.

0 900 1,800 2,700 3,600 4,500 Dec ’25Jan ’26Feb ’26Mar ’26Apr ’26May ’26
Natural Lab-grown

Explore the index

Why a standards site

Diamond grading tells you what a stone is. It does not tell you whether the price is fair, whether the same certificate is listed cheaper elsewhere, or whether a retailer's data can be trusted. The Caratlytics Score adds that market layer, and this site is its public record.

Caratlytics is developed by the team behind Carat Hunter, the diamond search engine where the score is applied to live inventory. We publish the full methodology here so that anyone can inspect it, challenge it and hold us to it.

Read our governance and disclosure

Have a certificate in hand? Compute an indicative quality grade in your browser. Try the score widget