4 Carat Lab Grown Diamond Rings: Prices by Shape

A 4 carat lab grown diamond ring starts at $5,999 at Liori, and the shape you pick moves both the price and how big the stone actually looks. Radiant, emerald, oval, cushion and pear all open at $5,999; round is the one shape that starts a tier higher, at $6,999. If you want the widest look on the finger, start with oval or emerald. If you want maximum sparkle, pay the round premium.

What a 4 carat lab grown diamond ring costs

Below is what each shape actually costs at Liori right now, in a complete ring: a 4 carat lab grown centre stone already set in white gold, not a loose stone plus a setting to budget for separately. Prices were pulled from live inventory on 20 August 2026. The range for each shape reflects how much accent work sits on the band, from a plain wire solitaire up to a vintage halo. Every one of these designs sits in our lab grown engagement ring collection.

Two things stand out. First, five of the six shapes share the same floor, so shape is a style decision at this weight rather than a budget decision. Second, round is the exception, and the gap is real money. If you have settled on a number rather than a shape, our lab grown diamond cost per carat ladder shows how the price behaves as weight climbs.

Radiant at 4 carats

Radiant is the shape people come to us for at this weight, and it is the one we keep the deepest bench of: six different 4 carat radiant designs are live today, from $5,999 for the petite wire basket solitaire to $7,999 for the vintage halo. It works because it borrows from both sides of the family. The outline is a rectangle with trimmed corners, like an emerald cut, so it covers a lot of finger. The faceting underneath is brilliant, like a round, so it throws light rather than sitting still.

That combination is forgiving in a way step cuts are not. Brilliant faceting breaks light up, which hides small inclusions and a touch of warmth that an emerald cut would put on display. At 4 carats that forgiveness is worth money, because it lets you buy a slightly lower clarity grade without seeing anything. Radiants do vary in how square or elongated they are cut, and that changes the look completely, so check the length-to-width ratio on the report before you commit. If you are torn between the two rectangular options, we compared them directly in radiant cut versus emerald cut, and you can see the live stones in the radiant cut collection.

Emerald at 4 carats

An emerald cut is a step cut. Instead of many small facets scattering light, it has long parallel planes that flash like a hall of mirrors. It reads calm and architectural, and it is the shape that most rewards restraint in the setting. At 4 carats it also reads long, which is why it suits people who want presence without a stone that shouts.

The trade-off is honesty. Those open planes show everything, so an inclusion that would vanish in a radiant sits there in plain sight, and any warmth in the body colour is easier to spot. This is the one shape where we tell people to buy the cleaner grade rather than the bigger accent stones. Our clarity scale explained from FL to I3 covers where the visible line falls. Emerald pricing matches the others, running $5,999 to $7,999 across the six designs in the emerald cut collection.

Oval at 4 carats

Oval is the shape to pick when covering the finger is the point. It is an elongated brilliant, so it keeps the sparkle of a round while stretching the outline, and at this weight that stretch is obvious rather than subtle. Five designs run from $5,999 to $7,999.

The thing to check is the bow-tie: a darker band across the middle of the stone caused by the way light behaves in an elongated brilliant. Every oval has one to some degree, and the question is only whether it is faint enough to ignore. Photographs flatten it, so look at video or see the stone in person before deciding. We go deeper on ratios and settings in our oval lab grown engagement ring guide, and the current stones sit in the oval cut collection.

Round at 4 carats

Round brilliants return more light than any other shape, and that is not marketing: it is what the facet pattern was designed to do, and every other cut is measured against it. If sparkle is the thing you care about, this is the shape.

You pay for it twice. Round is the only shape in our 4 carat range that starts at $6,999 rather than $5,999, and it also gives you the most compact outline of the six, so the same weight covers less finger. Buyers who want the classic accept both. Buyers who want scale usually move to radiant or oval once they see the two side by side. Cut grade matters more here than anywhere else, because a round with weak proportions loses the exact quality you paid extra for. Our guide to how cut quality affects sparkle explains what to look for on the report.

Cushion, pear and the shapes at the edges

Cushion is a pillow outline with softly rounded corners and a warm, romantic character. Four designs run $5,999 to $8,999. It is worth knowing that cushions carry more of their weight below the surface than a round does, so a 4 carat cushion reads a little smaller than the number suggests. That is a fair trade if you want the vintage look, and it is the reason we would not pick it for someone whose whole goal is scale. The stones are in the cushion cut collection.

Pear splits the difference: a brilliant lobe tapering to a single point, long on the finger and distinctly less common. Five designs start at $5,999. Marquise is the one shape we should be straight about: we stock it up to 3 carats, not at 4, so if your heart is set on a 4 carat marquise the answer today is a custom order rather than something you can add to a cart. For how all the outlines behave against each other, see every diamond shape compared.

How big 4 carats actually looks

Carat measures weight, not size. That distinction does real work at 4 carats. Two stones can weigh the same and still cover different amounts of finger, because the weight can sit deep in the stone or spread across its face. IGI puts it plainly: diamonds of the same carat weight can appear to be different sizes when viewed from above. The number that predicts what you will see is spread: the average of length and width, not the weight on the report.

The pattern follows the geometry. IGI notes that shallow shapes such as emerald cuts and marquise can appear larger from the top compared to the round, . Deeper shapes such as cushions carry more weight in the body, so they look smaller face-up. That is why an oval and a cushion of the same weight sit so differently on one hand.

One caution before you chase spread for its own sake. A very shallow stone does look larger under bright showroom lights. But IGI warns it is not necessarily the best choice for anyone who wants the diamond to look brightest and largest across many lighting environments. You want the stone that still looks big in a restaurant, not only under a spotlight. For a millimetre-level comparison at a smaller weight, see our shape-by-shape size breakdown.

What to insist on at 4 carats

A 4 carat stone is not a 1 carat stone scaled up. Everything is larger, including the flaws, so the grades you can comfortably compromise on shift. This is the floor we would hold to, and our current 4 carat designs all meet it:

• Cut first, always. At this size a weak cut is visible from across a room. Do not trade cut quality for weight or for a better colour letter.
• Clarity that is clean to the eye. In a brilliant shape such as radiant, oval or round you have room to move. In an emerald or asscher, buy the cleaner grade, because a step cut hides nothing.
• Colour judged in the setting. Warmth shows more in a big stone than a small one, but it also reads differently against white gold than against yellow. Our diamond colour chart from D through Z shows where the visible steps are.
• A report from GIA or IGI, and nothing else. Every Liori centre stone is certified by one of the two, with a report number you can check against the laboratory database.
• Prongs that match the stone. A 4 carat centre needs enough metal to hold it and a basket set low enough to live with. Pointed shapes such as pear and marquise need their tips protected.
• See the video, not the photograph. Bow-ties in ovals and windowing in step cuts both disappear in a still image and both show up in motion.

Why 4 carats is realistic in lab grown

Four carats is a size most people file under one day when they are shopping natural stones, and the reason it lands in reach here is the centre stone, not the workmanship around it. The clearest way to show that is to hold everything else constant. Below is one ring from our range, the 4 Carat Radiant Cut Under Halo Petite Micropave, in the identical setting with the identical accent diamonds, offered two ways.

Same design, same 4 carat weight, same white gold: $5,999 with a lab grown centre and $55,450 with a natural one. Both figures are our own live prices, and the comparison holds across the range rather than being one flattering pair. A lab grown diamond is chemically and optically a diamond, so what you are choosing between is origin and price, not quality. If you want the science, our explainer on HPHT versus CVD growth methods covers how these stones are made.

The fair objection is resale, and it deserves a straight answer rather than a dodge: lab grown stones do not hold value the way natural ones do, and anyone telling you otherwise is selling something. We wrote the honest version in our piece on lab grown diamond value and resale. If you are weighing the natural route at this weight, what a 4 carat ring is worth covers that side, and 10 carat ring prices show where the ladder goes next.

Frequently Asked Questions (FAQ)

Short answers to what buyers ask us most about 4 carat rings. If your question is not here, our diamond consultants are reachable around the clock.

How much is a 4 carat lab grown diamond ring?

At Liori a complete 4 carat lab grown ring starts at $5,999 in radiant, emerald, oval, cushion and pear, and at $6,999 in round. Designs with more accent work run to $7,999 and above. That price includes the certified centre stone already set in white gold. Browse the current selection in the lab grown engagement ring range.

Is a 4 carat ring considered big?

Yes. Four carats is well above the size most engagement rings are built around, and it reads as a statement stone on almost any hand. It covers a substantial part of the finger and it is immediately noticeable. If it feels like a step too far, the tier just below gives you most of the presence: our 3.5 carat lab grown rings start at $4,999. You can compare outlines in our guide to diamond shapes.

Which 4 carat shape looks biggest?

Elongated shapes cover the most finger. IGI notes that shallow shapes such as emerald cuts and marquise can appear larger from the top compared to the round, and oval behaves the same way. Round has the most compact outline of the six shapes we stock at this weight, and cushion reads slightly smaller than its weight suggests. For sheer coverage, oval and emerald lead, with radiant just behind them while keeping brilliant sparkle. Our oval range is the place to start if size is the priority.

Do lab grown diamonds hold their value?

Not the way natural diamonds do, and it is better to know that before you buy than after. A lab grown diamond is a real diamond by every physical and optical measure, but the resale market treats the two differently. The upside is that you are risking far less money in the first place. We set out the full picture, without the sales gloss, in our article on resale value and what to expect.

Is a 4 carat ring too big for everyday wear?

It depends far more on the setting than on the stone. A 4 carat centre set low in a sturdy basket with enough prongs wears comfortably day to day. A high cathedral setting on the same stone catches on clothing and knocks against things. If you work with your hands, ask for a lower profile and skip pointed shapes, whose tips are the most vulnerable part of the stone. A home try-on box answers this question faster than any photograph.

Are 4 carat studs the same as a 4 carat ring?

No, and the difference catches people out. In a pair of studs the four carats are split across two stones, so each ear holds roughly two carats. In a ring the full four carats sit in a single centre stone, which is why a 4 carat ring looks dramatically larger than 4 carat total weight studs and costs more per piece. If it is the pair you are after, we list those separately in our 4 carat stud collection.