4.2 Carat Round Lab Grown Diamond Prices Comparison
As of February 2026, 4.2 carat round lab grown diamonds usually range from $639 to $37,300, with an average price of $3,269.In the last month, prices for these diamonds are down 3.6%.Compare 546 verified listings across 9 retailers tracked by CaratRadar.
4.2 Carat Round Lab Grown Diamond Market Overview
CaratRadar currently tracks 546 verified 4.2-carat round lab grown diamonds listed across 9 online retailers. Prices in this segment range from $639 to $37,300, with an average asking price of $3,269 and a median of $1,626.
The price spread of $36,661 (98.3% from highest to lowest) highlights why comparing identical certified diamonds across multiple retailers matters. Two identical certified diamonds can differ by hundreds or even thousands of dollars depending on the retailer.
These figures are based on our latest daily market data, matched by certification lab and certificate number across retailers, so you are comparing the exact same diamond.
546 diamonds tracked in this segment
Price range: $639 to $37,300
Average price: $3,269
Median price: $1,626
Available across 9 retailers
Savings potential: up to 98.3%
Price Range Overview
As of Feb 28, 2026Real market range for this carat, shape, and diamond type.
546
$639
$3,269
$1,626
$37,300
Price History
Price Comparison Matrix
Live Listings
See all listingsCompare current retailer offers for this exact segment and open any listing for full details.
IGISave 92.9%4.16ct | Round | H | VS1 | Ideal
From $1,719
Compare at $24,064
IGISave 80.9%4.16ct | Round | D | VVS2 | Excellent
From $1,715
Compare at $8,980
IGISave 88.5%4.16ct | Round | F | SI1 | Ideal
From $665
Compare at $5,770
IGISave 80.3%4.16ct | Round | H | VS1 | Ideal
From $671
Compare at $3,410
GIASave 72%4.16ct | Round | D | FL | Excellent
From $28,728
Compare at $102,520
GIASave 70.6%4.16ct | Round | E | VS2 | Excellent
From $2,759
Compare at $9,390
IGISave 82.7%4.16ct | Round | G | VS1 | Ideal
From $1,031
Compare at $5,960
IGISave 83.7%4.16ct | Round | G | VS1 | Ideal
From $1,031
Compare at $6,340
GCALSave 63.8%4.16ct | Round | E | VS2 | Excellent
From $3,787
Compare at $10,460
GIASave 69%4.16ct | Round | E | VVS2 | Excellent
From $4,944
Compare at $15,970
GIASave 73%4.16ct | Round | D | VVS1 | Excellent
From $5,750
Compare at $21,310
GIASave 61.5%4.16ct | Round | D | VVS2 | Ideal
From $4,594
Compare at $11,920
GIASave 75.7%4.16ct | Round | D | VVS1 | Excellent
From $5,619
Compare at $23,139
GIASave 81.8%4.16ct | Round | D | VVS1 | Excellent
From $4,205
Compare at $23,104
GIASave 81.2%4.16ct | Round | D | VVS1 | Excellent
From $4,529
Compare at $24,080
GIASave 82.7%4.16ct | Round | D | VVS1 | Excellent
From $3,987
Compare at $23,104
IGISave 56.3%4.16ct | Round | G | SI1 | Ideal
From $1,144
Compare at $2,616
IGISave 84.8%4.16ct | Round | F | VVS2 | Ideal
From $1,670
Compare at $11,020
IGISave 80.2%4.16ct | Round | H | VS1 | Ideal
From $665
Compare at $3,360
IGISave 42.6%4.16ct | Round | H | VS1 | Ideal
From $1,955
Compare at $3,405
IGI4.16ct | Round | G | VS1 | Excellent
From $1,238
Compare at $1,368
IGISave 82.8%4.16ct | Round | D | IF | Ideal
From $5,276
Compare at $30,760
IGISave 72.3%4.16ct | Round | E | VS1 | Ideal
From $989
Compare at $3,575
IGISave 81.7%4.16ct | Round | D | VVS1 | Ideal
From $2,815
Compare at $15,420
IGISave 68.4%4.16ct | Round | F | VS1 | Excellent
From $1,039
Compare at $3,285
GIASave 62.6%4.16ct | Round | F | VVS1 | Ideal
From $7,076
Compare at $18,920
GIASave 77.8%4.16ct | Round | D | IF | Excellent
From $12,212
Compare at $55,100
GIASave 60.4%4.16ct | Round | D | VVS2 | Ideal
From $4,594
Compare at $11,610
GIASave 61.6%4.16ct | Round | F | SI1 | Ideal
From $3,702
Compare at $9,640
GIASave 59.3%4.16ct | Round | D | VVS2 | Ideal
From $4,594
Compare at $11,290
GIASave 82.2%4.16ct | Round | D | VVS1 | Excellent
From $4,296
Compare at $24,080
IGISave 68.9%4.16ct | Round | G | VS1 | Excellent
From $2,069
Compare at $6,650
IGISave 73%4.16ct | Round | E | VVS1 | Ideal
From $3,692
Compare at $13,680
IGISave 79.9%4.16ct | Round | F | SI1 | Ideal
From $685
Compare at $3,410
IGISave 88.5%4.16ct | Round | F | SI1 | Ideal
From $665
Compare at $5,770
IGISave 90.1%4.16ct | Round | G | VVS2 | Ideal
From $738
Compare at $7,460
IGISave 87.8%4.16ct | Round | G | VS1 | Ideal
From $748
Compare at $6,140
IGISave 85.8%4.16ct | Round | E | VS1 | Ideal
From $1,083
Compare at $7,640
IGISave 61.4%4.16ct | Round | E | VS1 | Very Good
From $1,241
Compare at $3,211
IGISave 17.1%4.16ct | Round | E | VVS2 | Excellent
From $1,319
Compare at $1,591
IGISave 66.2%4.16ct | Round | E | VS1 | Ideal
From $1,209
Compare at $3,575
IGISave 72.3%4.16ct | Round | E | VS1 | Ideal
From $989
Compare at $3,575
IGISave 72.3%4.16ct | Round | E | VS1 | Ideal
From $989
Compare at $3,575
IGISave 70.9%4.16ct | Round | E | VS1 | Ideal
From $1,040
Compare at $3,575
IGISave 89.5%4.16ct | Round | E | VVS1 | Ideal
From $1,642
Compare at $15,610
IGISave 63.2%4.16ct | Round | F | VS1 | Excellent
From $1,209
Compare at $3,285
GCALSave 77.2%4.16ct | Round | D | IF | Ideal
From $8,171
Compare at $35,820
GIASave 50.2%4.16ct | Round | E | VS1 | Ideal
From $5,040
Compare at $10,130
GIASave 80.8%4.16ct | Round | D | IF | Excellent
From $10,565
Compare at $55,100
IGISave 81.5%4.16ct | Round | F | VS2 | Ideal
From $1,338
Compare at $7,220
Entry pricing in this category starts around $639.
What to Know When Shopping for 4.2 Carat Round Lab Grown Diamonds
- Always compare identical certified diamonds across retailers. Identical certificate numbers can have price differences of $36,661 or more.
- Focus on the 4Cs that matter most to you. Color and clarity grades drive price more than cut in many segments, but cut affects sparkle the most.
- The median price of $1,626 is a useful benchmark. If you see a deal significantly below this, verify the retailer's reputation and return policy.
- Consider eye-clean alternatives. Moving one clarity grade down (e.g., VS2 to SI1) can save 10-15% with no visible difference to the naked eye.
- Lab-grown diamonds offer excellent value. Ensure the stone comes with a GIA or IGI certificate confirming it is laboratory-grown.
- Check shipping, insurance, and return policies. The lowest sticker price is not always the best deal once you factor in total cost of purchase.
- Round brilliants command a premium due to higher rough waste during cutting. If budget matters, consider oval or cushion shapes for similar visual size.
Frequently Asked Questions
We currently track 546 comparable stones in this segment. Prices start around $639 and go up to $37,300.
Based on the latest market data, the average asking price is about $3,269 with a median around $1,626.
The observed spread is roughly $36,661 across tracked listings, which is about 98.3% from highest to lowest offer in this bucket.
We refresh pricing data daily so these pages stay current with market changes.
Based on our data, the median price is $1,626, which represents the midpoint of the market. Anything below this figure from a reputable retailer is a solid deal.
We currently track this stone category across 9 online retailers, giving you a broad view of the competitive landscape.
For most buyers, color differences below G are hard to detect once set in a ring. Clarity grades of VS2 and above are typically eye-clean. Prioritize cut quality for maximum brilliance, then balance color and clarity based on your budget.
Retailer pricing strategies, overhead costs, and margin targets all contribute. The exact certified diamond can differ by $36,661 across sellers, which is why direct certified-diamond comparison is essential.
We match diamonds across retailers by their certification lab and certificate number. This means the prices you see are for the exact same physical diamond, not just stones with similar specs. It is a true apples-to-apples comparison.
Diamond prices fluctuate based on supply and demand. Our data refreshes regularly so you can track trends over time. Use the price range on this page as a benchmark and compare it to historical averages when available.
Diamond Terminology
- Carat
- A unit of weight for diamonds equal to 200 milligrams. Larger carat weights are exponentially rarer, which is why prices increase non-linearly with size.
- Cut
- Refers to how well a diamond's facets interact with light. Cut quality ranges from Ideal to Poor and is the single biggest factor affecting a diamond's brilliance.
- Color
- Grades a diamond's lack of color on a scale from D (colorless) to Z (light yellow). Grades D-F are considered colorless; G-J are near-colorless and offer good value.
- Clarity
- Measures the presence of internal inclusions or surface blemishes. Grades range from Flawless (FL) to Included (I3). Most inclusions in VS2 and above are invisible to the naked eye.
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