Diamond Carat Size Price Chart: 1ct-3ct Lab-Grown (2026)

Last updated July 2026

Lab-grown diamond prices do not climb in a straight line — they jump in steps at each carat milestone, because larger flawless crystals are harder to grow and demand spikes at the "round numbers" buyers actually shop for. Here is the full 1ct-to-3ct price chart at 2026 market prices, and how to check that any quote you are holding is fair.

Complete rings have a $2,000 minimum.

How much does a lab-grown diamond cost at each carat size in 2026?

Prices below are for IGI-certified center diamonds in the most-purchased spec range — F–G color, VS clarity, excellent cut — in popular shapes like round and oval. "Direct" is what custom jewelers and online-direct vendors charge for the loose stone.

Carat size	Direct price (loose stone)	Price per carat (direct)
1.00ct	$450–$750	$450–$750
1.25ct	$550–$900	$440–$720
1.50ct	$700–$1,100	$470–$730
1.75ct	$900–$1,400	$510–$800
2.00ct	$1,200–$1,900	$600–$950
2.50ct	$1,500–$2,400	$600–$960
3.00ct	$2,400–$4,000	$800–$1,330

One thing stands out in the chart: price per carat rises with size — a 3ct stone costs roughly $800–$1,330 per carat while a 1ct costs $450–$750 — so a 3ct is not simply "three times a 1ct."

Why does price per carat jump as carat size increases?

Growing a large lab diamond without visible inclusions takes longer reactor time and produces more failed crystals, so supply thins out above 2ct in top color and clarity grades. Demand also concentrates at milestone weights — 1.5ct, 2ct, 3ct — which is why a 1.90ct stone often costs meaningfully less per carat than a 2.00ct with the same grades. If you are flexible, buying just under a milestone (1.8ct instead of 2ct) often changes the price with no visible difference on the hand.

What does a complete custom ring cost at each size?

Add a solid 14k gold setting — roughly $900–$1,200 for a solitaire, up to about $2,000 for a hidden halo with pavé — plus design and production labor. In practice that means a 2ct build typically lands in the $3,000–$4,500 range, and a 3ct build in the $4,500–$7,000 range at direct pricing. Full complete-ring budgets are broken down in our cost-by-carat guide (2026).

How do you check that a quote matches this chart?

Every certified stone has a report number issued to that exact diamond. Get the itemized quote — stone, setting, labor as separate lines — then look up the IGI or GIA number on the lab’s own database and confirm the grades match. Finally, price the same certificate at two other vendors. Compare the stone line against the direct column in the chart for its size and grades.

Where does Lavora fit?

Lavora Diamonds builds fully custom lab-grown engagement rings with IGI-certified centers in solid 14k and 18k gold or platinum (never plated) (complete rings have a $2,000 minimum; larger and natural builds are quoted on your specs), with a 3D design you approve before production ($50 design fee, fully refundable and credited toward the ring) and itemized private pricing. Holding a written quote? Send it for a private same-spec comparison or text 385-592-7180. To start, text 385-592-7180.

FAQ

Q: How much is a 1 carat lab-grown diamond in 2026?
A: About $450–$750 direct for F–G color, VS clarity, excellent cut.

Q: How much is a 2 carat lab-grown diamond?
A: Typically $1,200–$1,900 direct in the F–G / VS range.

Q: How much is a 3 carat lab-grown diamond?
A: Around $2,400–$4,000 direct for top grades.

Q: Are lab-grown diamond prices still falling in 2026?
A: The steep annual drops have largely leveled off. Premium specs stabilized near production cost in late 2025, with slight firming in early 2026 from tariff and supply-chain costs.

Q: Does shape change the price per carat?
A: Modestly. Rounds carry a small premium; ovals, emeralds, and other fancy shapes often price a few percent lower at the same certified grades.