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Round Cut Lab Grown Diamonds: Prices by Carat, Cut and Grade

Rare Carat has 486,864 round cut lab grown diamonds in stock today, every carat weight, 386,897 of them with 360 HD video. They start at $120 with the current savings applied, and in the 0.90 to 1.10 carat band the median is $464, against $2,834 for a natural round of the same weight on the round cut diamonds page. The round brilliant is the one shape with a laboratory cut grade, and in lab grown it is also the shape where the grades run highest: most of the stones here are D to F color and VS clarity or better, so the decisions that cost thousands in a natural round cost tens of dollars in a lab one, and the money goes into size and cut instead. Each figure on this page is from inventory on October 17, 2026 and is refreshed regularly.

A lab round is a diamond, the same carbon crystal with the same hardness, fire and brilliance, grown in a reactor over a few weeks rather than in the earth over a billion years. It is graded on the same color, clarity and cut scales by the same laboratories, and its report number is laser inscribed on the girdle, usually with the letters LG. What differs is supply, and supply is why 486,864 of these stones are available at prices that a natural round has never reached.

Lab Grown Round Prices from Half a Carat to Five

The table below splits every lab round on this page into carat bands that add up to the headline count. The deepest band is 0.90 to 1.10 ct with 117,358 stones. Medians run $464 at one carat, $1,440 at two, $2,826 at three and $4,027 at four, which is to say that each extra carat in a lab round costs about what a natural round charges for an extra tenth. The jumps at the full carat marks that shape natural pricing are much smaller here, so there is little reason to buy 1.90 carats instead of 2.00 for the discount; buy the size you want. Above four carats, 34,824 stones from $2,125, the lab round reaches sizes that are rare in any natural inventory. Each band links to the matching lab carat page across all shapes.

Round cut lab grown diamonds by carat band, prices you pay today (486,864 stones, October 17, 2026)

Cut: The Grade That Still Separates Lab Rounds

Color and clarity are nearly solved in lab round brilliants, so cut is where the stones actually differ, and the supply has already sorted itself: 476,548 of the 486,864 rounds here are graded Ideal or Excellent, 9,465 Very Good and 851 Good. In the 0.90 to 1.10 carat band an Ideal or Excellent cut starts at $330 with a median of $464, against a median of $427 for Very Good and $403 for Good, so the top grade costs little or nothing extra. The cut grade measures how well the proportions return light; an Excellent round looks brighter and larger than a Good one of the same weight, and the difference is visible across a table, which is why our gemologists treat Excellent as the floor rather than an option. Rare Carat Ideal, our own tighter proportion band inside Excellent, is marked on the product page and in the filter.

Round cut lab grown diamonds by cut grade: stock on this page, and price in the 0.90 to 1.10 ct band (October 17, 2026)

Color and Clarity Ladders for a 1 Carat Lab Round

In the 0.90 to 1.10 carat band with clarity held at VS2 or better, 97 percent of the lab rounds on the color ladder are D to F, and D and G both start at $370 and H at $350. The colorless grades cost so little extra that there is no reason to go below F in a lab round unless a warmer stone is the point. Clarity is the same story from the other side: with color held at D to F, 67 percent of the stones on the clarity ladder are VVS2 or better, VS1 starts at $370, VVS2 at $380 and VVS1 at $465. Where a natural buyer saves by stepping down to SI1, a lab buyer saves almost nothing, so the sensible lab round is D to F, VS1 or better, Excellent cut, and the only remaining question is how large.

Round cut lab grown diamonds, 0.90 to 1.10 ct: starting price by color at VS2 or better (115,606 stones) and by clarity at D to F color (113,966 stones)

Lab Round Against Natural Round, Same Grade

Hold the grade fixed and the gap is plain. A one carat G color VS1 round starts at $370 lab grown and $1,475 natural (natural median $3,321); an E color VVS2 is $430 against $1,985. Across the whole one carat band the medians are $464 and $2,834, a ratio of about 6.1 to one, and at two carats $1,440 against $13,386. Both stones face up the same size, 6.4 to 6.5 mm at one carat and 8.1 mm at two, and both carry a report from GIA, IGI or GCAL. The natural round holds a scarcity that the lab round does not, which is the honest reason people still pay the difference; the lab round puts a larger, cleaner, better cut stone on the hand for the same money. Our lab grown diamonds guide and the article on what a 1 carat lab grown diamond costs go deeper.

Round cut, 0.90 to 1.10 ct, same grade

IGI, GIA or GCAL: Reports on Lab Grown Rounds

468,883 of the 486,864 lab round brilliants here carry IGI reports, 13,088 carry GIA reports and 4,893 carry GCAL reports. IGI graded the lab market first and still grades most of it; GIA now issues full lab grown reports with the same color, clarity and cut scales as its natural reports; GCAL adds an optical light performance analysis. All three state that the stone is laboratory grown and all three inscribe the report number on the girdle. Rare Carat does not grade diamonds, but every report is linked from the product page, the AI quality score out of 18 reads the grades on it, and after you order our New York staff put the stone under a microscope and match the inscription to the report before it ships.

Buying a Lab Grown Round at Rare Carat

Start from the size, since the grades take care of themselves. Set the filter to Excellent cut, D to F color and VS1 or better, then sort by price within the carat band you want and open the 360 HD video on the first few stones. Read the AI price score, which compares the stone with similar lab rounds in stock and flags one priced above its peers. Our gemologists will go through any shortlist with you by chat or phone, without commission, and will tell you when a stone two tenths lighter is the better buy.

Rare Carat is the merchant of record on each order and stocks more than 2 million natural and lab grown diamonds. Shipping is free and insured, returns are free for 30 days, resizing is free for the first year, and a lifetime manufacturing warranty covers every ring. Affirm, Klarna, Afterpay, PayPal Pay Later and Katapult are the payment plans offered at checkout. Rare Carat holds a 5 out of 5 rating on Google and Trustpilot, which ranks it the highest rated jewelry brand in America.

Counts and prices cover every round cut lab grown diamond in Rare Carat inventory on October 17, 2026 that the grid on this page shows, every carat weight: D to K color, FL to SI2 clarity, Good cut or better, GIA, IGI or GCAL graded, with or without video; 486,864 lab grown (386,897 with 360 HD video). Prices reflect the current savings, which apply automatically; regular prices are struck through on each stone. Starting prices are the lowest priced stone in the group, whatever its grade or weight. Color and clarity ladders are for the 0.90 to 1.10 carat band, so grade and not weight moves the price. Natural round comparisons use the same day and basis and come from the round cut diamonds page.