AltGems
Updated as of June 2026

Diamond Carat Guide

Carat is weight, not size. Cut and shape change how large a given carat weight looks.

Elongated shapes like oval and marquise look larger per carat. Buying just under a round number (0.9 vs 1.0 ct) saves money for a near-identical look.

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Frequently asked questions

Diamond Carat Guide?
Carat is weight, not size. Cut and shape change how large a given carat weight looks. Elongated shapes like oval and marquise look larger per carat. Buying just under a round number (0.9 vs 1.0 ct) saves money for a near-identical look.
What matters most?
Elongated shapes like oval and marquise look larger per carat. Buying just under a round number (0.9 vs 1.0 ct) saves money for a near-identical look.