Faceting diagrams, reimagined

Plan, design &
render gemstones
in your browser.

The whole faceting workflow in one place. Built for gem cutters who see the gem before the first cut. From rough to remarkable.

  • Your designs come with youBackward compatible with GemCAD (.gem, .asc) and Gem Cut Studio (.gcs). Import your library, keep working.
  • Realistic renderingTrue brilliance and color, previewed live as you design.
  • Best-yield rough plannerFit the finished gem inside your rough before a single cut.
  • Guided creatorFrom blank to finished diagram, one tier at a time.
Try it free See gallery

Free tier, no credit card, nothing to install. Opens .gem · .asc · .gcs · PDF diagrams.

The toolkit

Everything a working cutter needs

Design, cut, and hand off a finished stone without leaving the browser.

See more features in Docs

FROSTED FACETS

Add a little spice to your design.

You can frost individual facets one at a time, or you can frost an entire pavilion or crown at once using the Add Frosted Facets dialog. Both approaches apply the exact same frosting geometry.

Explore this feature
Frosted Facets
Pricing Plans

Certainty, before the first facet

Gem Diagram makes it easy to plan the rough before it goes on the dop, cut from a sequence you can follow, and hand the client something they can actually look at.

Sure of the roughSee the yield and the best orientation while the stone is still whole.
Sure at the machineThe cutting sequence stays in front of you, so you don't lose your place mid-stone.
Sure with the clientBefore work begins, hand over a render, a video or a screenshot, not a promise.
Monthly Yearly

Pay for the year instead and it drops to $20 a month.

Everything included

Pro

Every feature, one price.

$29/month

Billed monthly. Cancel anytime.

  • Design from scratch — Guided and Manual creators, full symmetry and index-wheel control
  • Your files, editable — .gem, .asc, .gcs and .facet in, PDF diagrams in, .facet out
  • Plan the rough — yield, best orientation, tilt search, photo-traced irregular rough
  • Cut from the sequence — Cutting Assistant with auto-cut, at-the-machine layout
  • Full realism — 22 materials with real RI and dispersion, color, frosting, Ray Studio
  • Hand it off — faceting diagram and stone report PDFs, screenshots, video, Client Preview links
See everything in Pro

Design & create

  • Gem Designer — angle, index and distance, tier by tier
  • Guided Mode creator with a 3-step setup wizard and live preview
  • Facet angles & index data
  • Symmetry control — n-fold rotation and mirror
  • Index wheel at any gear
  • Cut templates and pre-loaded reference gems to start from

See it

  • Live 3D preview — Solid and Realistic (ray-traced)
  • Ray Studio — trace light paths through the stone
  • Full materials library — 22 profiles with real RI and dispersion
  • Custom RI entry
  • Color editing (non-transparent) and color depth
  • Pleochroism — color shifts with the direction light travels
  • Frosted edges & facets, or click a facet to frost it
  • Gem Showcase (raytraced multi-gem lineup)
  • Themes and viewport controls

Plan the rough

  • Rough Planner — best orientation and finished weight
  • Auto, Tilt-search and Manual search modes
  • Irregular rough — photograph three views and trace the outlines
  • Pack several stones out of one piece
  • Size / Yield calculator

Cut it

  • Cutting Assistant — sequence, facets marked done, progress kept
  • Auto-cut — the Cutting Assistant drives the sequence
  • At-the-machine layout for a phone or tablet

Files & handoff

  • Upload unlimited diagrams
  • Import .gem, .asc, .gcs and .facet files
  • Import diagrams from PDF, scanned ones included
  • Edit + save file locally
  • Autosave, with your work restored when you come back
  • Export design as PDF — faceting diagram and stone report
  • Screenshots of renders
  • Record videos of renders
  • Client Preview (shareable branded gem pages)

Everywhere

  • All Free Demo features
  • Runs in any modern browser, nothing to install
  • Works on tablet and phone
  • 50+ pages of documentation
  • Report a bug from inside the app
Compare Free and Pro feature by feature
Get Pro

Free Demo

$0 per month

A showroom, not a bench. Look at everything, change nothing.

  • Every tool open to look through — Gem Designer, Cutting Assistant, Rough Planner
  • Full pre-loaded gem library in live 3D (solid + realistic)
  • Ray Studio and yield calculator on pre-loaded gems
  • Open your own .gem / .asc / .gcs files to view
  • View only — no saving, editing or exporting
Try it free No credit card required.

Pro is a subscription that renews automatically until canceled. Cancel anytime from your dashboard.

Compare all features

See the full feature matrix with all plans side by side.

View comparison

Common questions

Quick answers about plans, browsers, and getting started.

Gem Diagram reads .gem, .asc, and .gcs files. Import one from the top bar and it renders in 3D straight away. The Free Demo will show you the file; editing it, saving it and exporting it are Pro.
Gem Diagram runs in any modern browser with WebGL2 support, no install required. Check system requirements
Yes, as a demo. Every tool is open to look through — the pre-loaded gem library in 3D, Ray Studio, the yield calculator — and it will render your own files too. It is view only: saving, editing and exporting need Pro.
$29 a month, or $240 for the year, which works out to less than $1 a day. Cancel anytime from your dashboard.
No. The Free Demo never asks for one. Pro needs an active subscription.
With Pro, yes — faceting diagram PDFs with the cutting specifications, screenshots, and video of your renders.
Gem Diagram has 22+ material profiles including sapphire, emerald, ruby and tourmaline, with accurate RI and dispersion values.
No caps. Pro lets you open, edit and save as many designs as you want.
💬

Still have questions?

Send us a note and we'll get back to you quickly.

Contact Support Team
22+ Materials Library
Gemstone materials with accurate RI & dispersion
3 Render Engines
Solid, Realistic, and Ray Studio modes
PDF Faceting Diagrams
Export facet sequences and specs, ready for the lap
100% Browser-Based
Zero setup, nothing to install
Gem Diagram on desktop, laptop, tablet, and phone

Ready to design your next gem?

Plan the stone, cut it with a live guide, and send clients the render. It all runs in your browser.

No credit card, nothing to install.

Get started free