The Jewelry Box


The Jewelry Box Blog

Diamond Size Chart & 4 More Tools You Shouldn’t Shop Without

on Mar 15, 2016 6:10 PM

You know that feeling when you sit down to take a test and, even though you’re fully prepared, your mind goes blank?

Diamond shopping can feel similarly overwhelming. There’s so much to know about the details of a diamond – how to spot an imperfection, how a diamond’s shape affects its shine factor, whether carat or color is more important for maximum sparkle ... the list goes on.

Avoid flashbacks to high school test anxiety with these handy cheat sheets as your diamond shopping sidekicks. No memorization required.

Diamond Size Chart & 4 More Tools You Shouldn't Shop Without

Diamond Size Chart

One of the most helpful tools is a diamond size chart. While lots of jewelers and jewelry industry sources provide size charts for round diamonds, not as many allow you to compare carat weights across the most popular shapes.

Check out our Diamond Carat Size Chart, a visual comparison of diamonds in the 10 most popular shapes, ranging from 0.25 to 5 carats. It also lists the actual diameters of each diamond, as measured through the girdle.

Diamond Size Chart

Just make sure to set page scaling to “none” when you print so your chart displays accurately.

Ring Sizer

Especially important when gifting jewelry, a printable ring sizer is a simple way to determine your ring size. Print our Ring Sizer, grab a ring you (or your recipient) already own, and find the circle that matches in size. Easy as that!

Ring Size Chart

Like the diamond chart, make sure you set page scaling to “none,” as the ring measurements are very precise.

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Alternatively, most jewelers will provide a physical ring sizer free of charge. Great if you’re measuring your own finger, not so great if you’re trying to secretly get the ring size of your significant other. (Please take a video if you attempt this in their sleep. We’d love to see that.)

Pro Tips:

  • When considering a wide band, move up a size from your measurement, for comfort’s sake.
  • Your ring size will be about half a size larger on your primary hand (i.e. the hand you write with).


4Cs Quick Guide

There’s a lot you can learn about the 4Cs if you have the time and desire to dig deep. However, if you want a simple crash course in a printable format, Jewelers of America has just the thing.

They created a visual Guide to the Diamond 4Cs that shows the scales for carat, clarity, color and cut, as well as 12 of the most common diamond shapes.

Jewelers of America's Guide to the Diamond 4Cs

For a more comprehensive resource, you can read their Guide to Buying Diamond Jewelry or head to Ritani’s Diamond Education section for a fun, interactive way to learn all about the 4Cs (or is it 7?).

Diamond Grading Report

Important for appraisals, you’ll want to make sure to get a copy of the grading reports for each diamond you’re considering. While this isn’t something you can do ahead of time, you can learn a little bit about them beforehand.

Jewelers of America has an overview of diamond grading reports in general. You can also learn more about diamond reports and services from the Gemological Institute of America (GIA) and from American Gem Society (AGS), the institutions most commonly used for grading.

GIA Diamond eReport

Mobile Playbook

Last but not least, we couldn’t talk about portable tools without talking about apps.

GIA created a free 4Cs app, providing diamond knowledge on-the-go as well as access to their Retailer Lookup and Report Check services. (That way you’ll know right away if your jeweler has given you an official GIA diamond grading report or not.) Download it for iPad, iPhone or on Google Play.

GIA 4Cs Guide app

With all these resources, you’ll be a diamond expert in no time. Be gone, diamond shopping anxiety!

Bonus Fun: Want to try on some of your favorite styles before you get to the store?

Check out the apps from Blue Nile and Tiffany & Co. – both feature “Try It On” tools that allow you to snap a picture of your hand and pinch, rotate and drag different rings onto your finger.

Blue Nile app  Tiffany & Co. app

Go ahead, throw a 6 carat heart-shaped diamond on your finger and pretend you’re Lady Gaga. A girl can dream, right?


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Dear Sir / Madam
Pretty please where can I buy accessories for measuring diamonds?

Thanks in advance
Nenad Vrhovski

Nenad Vrhovski

I need some type f gauge to determine heart shaped diamond rings. Some have the ct. size engraved inside my rings and others do not. The .30-.48 and .60 and above. How can I get some chart to hold above the diamond head. I do not know where to find this. Can you help me out.


Debra Curry

In reply to by Anonymous (not verified)

Hi Debra - I'm not sure where to find something like this either. Even if you did, I don't think it would be particularly reliable. Your best bet is to take your rings to a local jeweler and have them help you. Sounds like you may want to consider getting them appraised. Thanks for reading; hope that helps.

Chelsea Drusch

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