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Diamond Price in 2026: How Much Does a Diamond Cost by Carat?
The price of a diamond in 2026 depends on four fundamental criteria — the 4Cs: Carat (weight), Cut, Clarity, and Color. Mastering these parameters will allow you to better understand the value of your stone and secure the best price when selling or buying.
The 4Cs that determine the price of a diamond
1. Carat (weight)
This is the most immediately visible factor. The price per carat increases exponentially with weight: a 2-carat diamond is not twice as expensive as a 1-carat diamond, but often 3 to 5 times more, because larger stones are rare.
2. Color
The GIA scale ranges from D (colorless, the rarest and most valuable) to Z (yellowish tint). Diamonds D to F are called “exceptional” and command a significant premium. G to J offer the best value for money.
3. Clarity
From IF (Internally Flawless — no visible defects) to I3 (very visible inclusions). Clarity VVS1 and VVS2 represent excellence. A VS1-VS2 diamond offers an excellent quality-to-price ratio, as inclusions are invisible to the naked eye.
4. Cut
The cut determines the stone’s brilliance. An “Excellent” or “Ideal cut” diamond can be worth 20% to 40% more than an identical diamond with a “Good” cut. The round brilliant cut remains the most valued on the resale market.
Diamond price by weight in 2026
| Weight | Entry-level | Mid-range | High-end |
|---|---|---|---|
| 0.30 ct | €500 | €1,000 | €2,000 |
| 0.50 ct | €1,200 | €2,500 | €5,000 |
| 1.00 ct | €3,500 | €7,000 | €18,000 |
| 2.00 ct | €10,000 | €22,000 | €60,000 |
| 3.00 ct | €22,000 | €45,000 | €120,000 |
| 5.00 ct | €50,000 | €100,000 | €300,000+ |
Diamond with or without a certificate: what price difference?
A GIA-certified diamond generally sells for 15% to 30% more than an uncertified stone with the same characteristics. The GIA certificate is the global reference; IGI is also recognized but with a slight discount.
Get a free appraisal for your diamond
Do you own a diamond and want to know its exact value in 2026? Diamantaires Paris OG offers you a free and non-binding appraisal. Our GIA-certified gemologists analyze your stone and provide you with an evaluation based on current market prices.
Schedule an appointment at our boutique in the heart of Paris or submit a request online. If you wish to sell, we guarantee to beat any competing offer.
Free, no-obligation estimate
Combien valent vos bijoux ?
In-person appraisal by a state-certified gemologist — firm offer, immediate payment, in complete confidentiality.