Gem Carat Weight Calculator™

The business grade gemstone & mineral weight calculation tool.
Includes weight calculation tools, crystal/gemstone and facet data, in an intuitive and browsable format.


A look at the features


Browse gemstones with ease

Extensive A-Z of gemstone and mineralogical data.

We have an extensive, hand-curated, database of gemstones, crystals and minerals laid out in a clear A-Z list.  For speed of access, our complete A-Z list is split across three tabs. 

Every gemstone in our app has it's own bespoke information profile, which includes an image and an array of data including geological and mineralogical properties.

Perform weight calculations

Fast and accurate, three stage calculation.

By combining industry accepted formulae with our comprehensive, proprietary gemstone and facet / cut databases, we are able to bring you an app that performs accurate calculations efficiently, right from your pocket!

Gem Carat Weight Calculator allows fast, accurate weight calculations to be performed by taking a few simple measurements for diamonds, sapphires, emeralds and 300+ other crystals.


Keep track of your calculations

Retain historical calculations for rapid reference

Great for those who perform regular or routine calculations ready to generate quotes against current market values.

Calculations include a number of tolerance values, allowing for quick, bulk appraisals.

A breakdown of the features

✪  Calculates gemstone carat weight, gram weight and tolerance value ranges.
✪  Contains 300+ gemstones and over 60 facet/cut types.
✪  Browsable A-Z list of crystals, gemstones and minerals, each with its own image and complete geological profile.
✪  Glossary of mineralogical terms and definitions.
✪  Reference charts.
✪  Directly compare gemstone profiles.
✪  Unit conversion tool.
✪  Full history of calculations for fast consults.
✪  Free database updates.

◼️  Language is English only.

Our licensing policy can be found at
Our refunds policy can be found at

We support our apps. If you run in to a problem, please drop us an email rather than a Play Store comment, and we can work with you directly to resolve the issue. Alternatively, visit our website at where we have support articles and FAQ's.


Frequently Asked Questions

Where can I purchase the apps?

Our apps are available for purchase exclusively on the Google Play Store.  Please click here to visit our store page.

Do you have Apple iOS or Amazon Fire apps?

Our apps are currently exclusive to the Android platform.  We do not have any iOS or FireOS versions at this time.

Do you support phones & tablets?

Yes. We support both phones and tablets running Android 4.4 (KitKat) and above.

View more FAQ & Support articles...

Click above to find a selection of our commonly asked questions and support articles. If you have a question that isn't covered, please feel free to drop us an email.


What Our Users Say


Available now for Android™ phones and tablets*.  Exclusive to the Google Play Store.

*Works on Android Kitkat (4.4) and above.


Get in touch with our team by email
or via our community forum

Community Discussion Forum