How much does a 1.00 to 1.49ct I SI2 lab grown round diamond cost?

As of October 2026, 1.00 to 1.49ct I SI2 lab grown round diamonds typically cost $675 USD to $2,711 USD, with a median price of $1,605 USD. There are currently 45 diamonds matching this specification available across retailers.

Where can I find the best price on a I SI2 round diamond?

About 22% of these diamonds are available at multiple retailers, with an average price spread of 92%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.00 to 1.49ct I SI2 Lab Grown Round

Quick answer

As of October 2026, there are 45 lab grown round diamonds with I color and SI2 clarity in the 1.00 to 1.49ct range available across retailers worldwide. Prices typically run $675 USD to $2,711 USD, with a median of $1,605 USD. At least 28 retailers stock this exact specification, and 22% of the stones appear at more than one of them, with an average price spread of 92%. Half of all listings fall between $813 USD and $2,284 USD per carat. The same specification in natural form lists at a median of about $2,600 USD per carat. Over the last 30 days the median price moved -24.2% and the number of listings moved -14.0%.

Three of the best scored stones at this specification right now:

Caratlytics Diamond Price Index, September 2026: natural diamonds at 2,335 USD per carat and lab-grown at 443 USD per carat, a natural to lab ratio of 5.3 to 1. Round lab grown stones in the index: 414 USD per carat, -5.0% month on month. See the full index release

Figures come from current listings across more than 100 retailers and refresh daily. The index is a monthly release.

Last updated: October 2026

Available

Lowest Price

$225 USD

Highest Price

$5,829 USD

Average Price

$1,649 USD

Market Intelligence

Retailers Selling

Cross Retailer %

22.5%

Price Spread

92.0%

30-Day Price Trend

-24.2%

30-Day Supply Change

-14.0%

Volatility (30d)

0.06

Price Range

Price per carat distribution across retailers

$1,599/ct

10th Percentile

$527

Median

$1,599

90th Percentile

$3,800

Score Distribution

103 diamonds scored across 4 quality tiers

Excellent

34 (33.0%)

Very Good

5 (4.9%)

Good

17 (16.5%)

Average

47 (45.6%)

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Related Specifications

D IF D VVS1 D VVS2 D VS1 D VS2 D SI1 E IF E VVS1 E VVS2 E VS1 E VS2 E SI1 F IF F VVS1 F VVS2 F VS1 F VS2 F SI1 G IF G VVS1 G VVS2 G VS1 G VS2 G SI1 H IF H VVS1 H VVS2 H VS1 H VS2 H SI1 I IF I VVS1 I VVS2 I VS1 I VS2 I SI1