How much does a 1.5-carat lab-grown diamond cost?
In our September 2026 comparison, a loose 1.5-carat lab-grown diamond cost $365 to $1,206. Ritani had the lowest benchmark and Blue Nile the highest. The seller-balanced typical price was $970.
We compared round diamonds from 1.45 to 1.55 carats, with E color, VVS2 clarity, and a high cut grade. Those grades make the seller comparison consistent, but most buyers can lower the color and clarity without seeing a difference. The prices do not include a ring setting.
Ritani was exceptionally inexpensive: the five lowest qualifying round stones all cost $365. That is why we use one result per seller rather than an inventory-wide average.
Read our Ritani review See 1.5-carat diamonds at Ritani
1.5-carat lab-grown diamond prices in 2026
“Typical” is the median of the seller benchmark prices above. Each seller counts once, so a jeweler with a much larger inventory cannot pull the figure down simply by listing more diamonds.
| Seller and sample | Price | Difference |
|---|---|---|
| RitaniMedian of five lowest results from the authorized API sample | $365 | Lowest in our test |
| With Clarity1.50 ct public sale price | $910 | 149.3% more |
| Brilliant EarthMedian of five lowest close feed results; grading lab not supplied | $970 | 165.8% more |
| Grown Brilliance1.50 ct current public price | $1,125 | 208.2% more |
| Blue Nile1.50 ct current IGI Ideal-cut result | $1,206 | 230.4% more |
The difference between sellers is large even though the target grades are close. A higher price may buy a better ring builder, showrooms, designs, service, or inspection experience, but it does not automatically mean the loose diamond is better.
Is 1.5 carats a good engagement-ring size?
A well-proportioned 1.5-carat round diamond is usually about 7.3 to 7.4 millimeters across. It looks substantially larger than one carat while remaining easy to wear in many settings. For many buyers, it is the sweet spot between visible size and a ring that does not dominate the hand.
Elongated shapes can appear larger still. An oval, pear, marquise, or radiant often gives more finger coverage than a round diamond of the same weight. Compare the actual length and width, because two 1.5-carat stones can face up very differently.
What changes the price?
Cut has the greatest effect on beauty. A weakly cut diamond can look dark, glassy, or smaller than its carat weight. Start with the grading report, but make the final decision from the actual video and measurements.
E/VVS2 is a high-grade benchmark, not our default recommendation. A well-cut G or H diamond with eye-clean VS1 or VS2 clarity often offers better value. At 1.5 carats, inclusions and tint are easier to see than in a half-carat stone, so inspect each candidate rather than relying only on the grade.
Search just below 1.50 too. A well-cut 1.45- to 1.49-carat diamond can be almost indistinguishable in size and may avoid the premium attached to the milestone.
1.5-carat round versus fancy-shaped diamonds
Fancy shapes can offer excellent value. Elongated ovals, pears, marquises, and emerald cuts often look larger than a 1.5-carat round diamond. Some shapes cost less, but the price changes with demand, proportions, and how efficiently each stone was cut.
To compare shapes without mixing in different seller markups, we used the five lowest qualifying Ritani API results for each of ten shapes. Every diamond was 1.45 to 1.55 carats, E color, VVS2 clarity, and IGI graded. Round diamonds had Ritani's Ideal label; the fancy shapes had Very Good or better cut labels. In total, 7,900 Ritani diamonds met those rules.
| Shape | Median price | Sample range | Cut used |
|---|---|---|---|
| Round | $365 | $365–$365 | Ideal |
| Oval | $384 | $382–$384 | Very Good |
| Emerald | $360 | $360–$362 | Very Good |
| Pear | $392 | $364–$394 | Very Good |
| Marquise | $391 | $391–$391 | Very Good |
| Radiant | $370 | $349–$381 | Very Good |
| Cushion | $383 | $382–$385 | Very Good |
| Princess | $387 | $379–$395 | Very Good |
| Asscher | $385 | $381–$385 | Very Good |
| Heart | $428 | $423–$428 | Very Good |
Emerald had the lowest five-listing median at $360. Heart was highest at $428. The spread was narrow: most shapes clustered within about $70. Inventory changes quickly, so choose a shape for its look rather than assuming one will always be cheapest.
Current 1.5-carat examples
round · IGI
$365
1.45 ct · E · VVS2 · Ideal
Lowest qualifying round result in the API capture.
Visit Ritani
oval · IGI
$382
1.48 ct · E · VVS2 · Very Good
Lowest qualifying oval result in the API capture.
Visit Ritani
emerald · IGI
$360
1.50 ct · E · VVS2 · Very Good
Lowest qualifying emerald result in the API capture.
Visit Ritani
pear · IGI
$364
1.47 ct · E · VVS2 · Very Good
Lowest qualifying pear result in the API capture.
Visit RitaniRitani's catalog images show each diamond shape, not the exact stones in our sample. Listings and prices can change after our check, so confirm the current diamond on the seller's site.
For fancy shapes, judge outline and symmetry carefully. Check ovals, pears, and marquises for a distracting bow tie; emerald and Asscher cuts for dead or see-through areas; and cushions and radiants for the pattern of sparkle you prefer.
Two 1.5-carat ring ideas
The original guide used ring examples because the setting changes how a 1.5-carat center looks. That remains more useful than viewing the loose diamond alone.
A slim solitaire makes the center stone look prominent and keeps the final price easy to compare.
A pavé or detailed band adds sparkle, but it also increases the finished-ring price. Compare the setting and diamond separately before comparing totals.
Compare lab-grown engagement-ring prices
Where should you buy a 1.5-carat diamond?
Ritani: best for loose-diamond value
Ritani had the lowest price by a wide margin, along with a huge inventory and clear cost information. It is the first seller we would check.
Read our Ritani review Visit Ritani
With Clarity: good balance of service, settings, and price
With Clarity's current benchmark was $910, and we have worked with the company since the site's early years. Its home-preview approach and engagement-ring experience can make it a good middle-ground choice.
Read our With Clarity review Visit With Clarity
Blue Nile: best all-round shopping experience
Blue Nile cost more in this test, but its diamond videos, ring builder, support, showrooms, and James Allen collection make it a polished alternative.
Read our Blue Nile review Visit Blue Nile
Grown Brilliance and Brilliant Earth
Grown Brilliance is particularly strong for distinctive settings and finished jewelry. Brilliant Earth is worth considering for its showrooms, designs, and specifically labeled sustainability collections.
Read our Grown Brilliance review Visit Grown Brilliance
Is a 1.5-carat lab-grown diamond worth it?
It can be an excellent value if you want a clearly visible center stone without the cost of a comparable mined diamond. Lab-grown diamonds are real diamonds with the same crystal structure and optical properties as mined diamonds.
The trade-off is resale. Values are weak and may fall as production becomes cheaper, so buy the ring to wear rather than as an investment. Sustainability is also not automatic; look for specific evidence about energy, carbon, metal, and manufacturing when it matters to you.
How 1.5-carat prices have changed
Our October 2024 comparison found round 1.5-carat prices from $588 to $2,350 across six sellers. Those figures used I–J color and VS1–VS2 clarity and were seller ranges. The current E/VVS2 benchmark is narrower, so the table below preserves history without pretending the methods are identical.
October 2024 archive
$588–$2,350
6 sellers · Round diamonds near 1.5 carats, I–J color, VS1–VS2 clarity, and Excellent or Ideal cut; seller ranges rather than one shared aggregation.
September 2026 test
$365–$1,206
5 sellers · Round diamonds from 1.45 to 1.55 carats, E color, VVS2 clarity, and a high cut grade; IGI grading where the source exposed it.
The older and current ranges show how dramatically prices have moved, but they are not a like-for-like index: our earlier study used lower color and clarity grades and reported seller ranges.
See our october 2024 fancy-shape archive
Starting prices near 1.5 carats, I–J color, VS1–VS2 clarity, and Very Good or better seller-reported cut. Individual listings are no longer current.
| Seller | oval | emerald | pear | princess | radiant | cushion | heart |
|---|---|---|---|---|---|---|---|
| Ritani | $584 | $474 | $545 | $600 | $456 | $507 | $617 |
| Grown Brilliance | $995 | $690 | $1,015 | $685 | $675 | $995 | $2,000 |
| Clean Origin | $884 | $674 | $660 | $851 | $694 | $855 | $1,110 |
| With Clarity | $905 | $925 | — | $1,083 | $992 | $990 | — |
| Brilliant Earth | $1,560 | $1,470 | $1,540 | $1,630 | $1,540 | $1,620 | $1,850 |
| James Allen (historical) | $1,650 | $1,670 | $1,940 | $2,260 | $1,660 | $1,700 | $2,650 |
Our verdict
Close 1.5-carat lab-grown diamonds cost $365 to $1,206 in our September 2026 test, with a seller-balanced typical price of $970. Ritani is the first place we would compare. With Clarity offers a useful middle ground; Blue Nile is the strongest all-round alternative.
Prioritize cut, inspect the actual stone, and compare measurements just below 1.50 carats before paying for the exact milestone.
How we researched 1.5-carat prices
We checked US listings on September 3, 2026. The target was 1.45–1.55 carats, E color, VVS2 clarity, and a high cut grade. Ritani's complete filtered API capture produced 7,900 qualifying offers across ten shapes. Brilliant Earth's feed supplied 212 close high-cut round results but does not expose the grading lab. With Clarity, Grown Brilliance, and Blue Nile contributed current public matches.
The current shape table compares shapes within Ritani, so different seller markups do not distort the result. Each seller contributes one benchmark to the seller-balanced typical price.
For the seller-balanced typical price, we take the median of the seller benchmark prices. Each seller contributes one benchmark, regardless of inventory size.
Ritani's complete filtered API capture produced 7,900 qualifying diamonds across ten shapes. Brilliant Earth's feed supplied 212 close high-cut round results but does not expose the grading lab. With Clarity, Grown Brilliance, and Blue Nile use close current public listings checked on September 3, 2026.
We kept the October 2024 seller and shape research as a dated archive. The current seller table and current shape table are separate on purpose: the former compares places to buy, while the latter holds the seller steady to compare shapes.
Compare other carat weights
- 0.5-carat lab-grown diamond prices
- 0.75-carat lab-grown diamond prices
- 1-carat lab-grown diamond prices
- 2-carat lab-grown diamond prices
- 3-carat lab-grown diamond prices
- 4-carat lab-grown diamond prices
- 5-carat lab-grown diamond prices
- 6-carat lab-grown diamond prices
Update history
This guide was first published in March 2024 and updated as the market changed. The September 2026 edition adds a five-seller benchmark, like-for-like ten-shape API comparison, current examples, and restored ring imagery while preserving the original buying advice and historical research.