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Diamond Price Calculator

Use our free diamond price calculator to estimate the current retail price for diamonds. Our price estimates are updated daily based on our massive database of online jeweler inventory sourced from top-rated jewelers. To see more diamond data and up-to-date price charts, visit our diamond price indexes page.

Updated: Wednesday September 27, 2023


Diamond Price Calculator Help


The StoneAlgo Diamond Price Calculator is based on the live prices of GIA certified diamonds. Be aware that different grading agencies have different grading standards.


Diamonds come in a variety of shapes including round and fancy shapes like cushion, oval, emerald, princess, pear, asscher, radiant, marquise, and heart shape.


The GIA grades diamonds on a scale from D to Z, where D represents a perfectly white diamond with no hue of color. Most jewelers recommend diamonds in the D - K color range.


Diamond clarity grades measure the inclusions and blemishes present in a diamond. Most jewelers recommend considering the FL - VS2 clarity range.


Carat weight is a measure of diamond size based on weight, where 1 carat is equal to 0.2 grams. The average carat weight for an engagement ring center stone is 1.10 carats in the US.


The GIA only assigns cut grades to round diamonds, but some online jewelers market their fancy shape diamonds as “excellent cut” (purely a marketing ploy). Cut quality can vary significantly even within the excellent cut grade, which is why we created our Cut Score.


Polish is graded on a scale of excellent to poor based on the presence of imperfections left on the exterior of the diamond by the polishing process.


Symmetry is graded based on how perfectly symmetrical a diamond’s dimensions and angles are when viewed under 10x magnification. We recommend excellent symmetry for round diamonds and at least very good for fancy shapes.


Some diamonds (roughly 33%) show some fluorescent glow when exposed to UV lights. The magnitude of this glow is measured by the fluorescence grade and we typically recommend considering None, Faint, or Medium. Read more in our Diamond Fluorescence Guide.


Our diamond price calculator assumes that your diamond is of average quality for whatever its specifications may be. For example, some SI1 clarity grade diamonds may be eye clean but most are not. If you are trying to price an eye-clean SI1 diamond you can expect that it should price higher than our calculators estimate.

Fair Price

We estimate the fair price of diamonds based on a massive database of live diamond prices shared by our top online jewelers. You can search this database using our diamond search engine to see the diamonds that are informing our pricing algorithm. Want an even more accurate price estimate? Try our Diamond Price & Quality Check to lookup any GIA diamond and get an algorithmic price estimate.

More ways to use our Diamond Price Calculator

Our diamond price calculator uses an advanced machine learning algorithm to provide you with the most accurate price estimate based on over 2,000,000 daily diamond prices from top online jewelers. Here are some other ways you can use our tool.

Diamond Price Per Carat Calculator

Our diamond price calculator provides you with the final price for a diamond but you can easily calculate the price per carat by dividing that final price by the carat weight of your diamond. Diamonds are priced in terms of price per carat because it is easier for diamond dealers to discuss pricing in these terms. Larger carat sizes are more rare, so price per carat grows. This leads to a compounding effect: larger diamonds cost more per carat and are larger in carat weight, both of which lead to a higher final price.

Diamond Worth Calculator For Selling A Diamond

If you are looking to sell your diamond you should know that you’ll take a “haircut” on the value of the diamond, and probably take a loss on what you paid originally (diamonds aren’t a great investment unless you are in the industry and have access to trading with other dealers - typically in large bulk volumes). The best way to avoid losing a lot of money when reselling your diamond? Make sure you got a good deal when you first purchased it. The second best way is to educate yourself on the fair market value for selling a stone. There are several websites that can help you sell your diamond including Worthy (our favorite), I Do Now I Don’t, Have You Seen The Ring, Ebay, & of course Craigslist.

Diamond Price Check For Diamond Appraisal

If you’re looking to get your diamond insured you’ll need an appraisal of your diamond jewelry. As you can see in our diamond price charts, diamond prices change over time and have risen historically, meaning it’s a smart idea to update your insurance policy every few years to reflect the present value of your possessions. If you know the price you paid for the jewelry setting itself, you can update your insurance policy to reflect the price changes for the diamond itself. Typically the larger loose diamonds are the most valuable part of your jewelry and will lead to the majority of the price change in the item.

Your Own Version of the Rapaport Price Calculator

Industry insiders like dealers and jewelers have access to a tool called RapNet that supplies them with pricing and inventory information. A RapNet account grants users access to a live diamond data feed as well as a weekly price list (the Rapaport Price List) that gives generic, high valuations for diamond prices which jewelers then manipulate to sell diamonds. The prices are intentionally high so jewelers can show consumers and act as if they’re providing the consumer with a great deal.

RapNet & the Rapaport Price List created information asymmetry where the average person has had far less information than the typical jeweler, and hence led us to create StoneAlgo so we could level the playing field. This same issue was a pain point in the real estate market as well until companies like Zillow, Trulia, and RedFin built databases of information to help home buyers find better deals on real estate. We hope to do the same for your diamond purchase or sale.

Comparing Diamonds of Different Color & Clarity Grades

It can be difficult to understand which diamond is a better deal when you’re comparing apples and oranges. Using our Diamond Price Calculator you can quickly see what the fair price of each diamond is and run a simple calculation to see which is the best deal. Make sure you also use our FREE diamond checker to get more details than just the price (like Cut Score and Visual Carat) to make the best comparisons.

Engagement Ring Budget Calculator

There is no right answer to how much you should spend on an engagement ring but the average engagement ring costs approximately $5,900 according to a 2019 study conducted by The Knot. At StoneAlgo, we’ve seen people spend anything from a few hundred dollars to hundreds of thousands of dollars on diamond engagement rings.

Our best advice is to have a conversation with your loved one to try to figure out what carat weight of diamond they’re expecting and what aspects of the diamond matter most: the color, clarity, or carat weight (we’d say cut but this always matters for round diamonds).

Based on your loved ones feedback and your current financial situation you should play around with the diamond price calculator to find a color and clarity grade that work best for you. Generally we advise color grades G - J and clarity grades VS2 or VS1. Any higher and you’re typically overpaying for quality that you’ll never be able to see with the naked eye. That said, our founder’s own engagement ring purchase was actually a VVS2 diamond that was wildly underpriced and this does happen due to certain supply and demand imbalances.

What Our Price Calculator Is Not

  • A Wholesale Diamond Price Calculator (we use diamond jeweler listings for pricing information, not wholesale listings)
  • A price or value guarantee that you can use to sell your diamond
  • An indication of an offer to purchase your diamond
  • An assessment of your particular diamond based on the unique inclusions or other specifications which are not completely standardized in the grading process.
  • A price estimate for IGI certified diamonds, EGL certified diamonds, AGS certified diamonds.
  • A lab grown diamond price calculator