--- title: "How Big Is a Pearl? See Pearl Sizes at True Size" description: "See pearls drawn at true size, from 1 to 20 mm across, next to a US quarter and the typical sizes of Akoya, freshwater, South Sea, Tahitian and keshi pearls." canonical_url: "https://learnaboutpearls.com/tools/pearl-size-visualizer/" last_updated: "2026-11-04" last_reviewed: "2026-10-26" reviewed_by: "Simon" publisher: "Unique Pearl" publisher_disclosure: "Learn About Pearls is published by Unique Pearl, a pearl jeweler." --- # How Big Is a Pearl? See Pearl Sizes at True Size A pearl’s size is its diameter in millimeters. [1] Choose a size below to see a pearl drawn at that size, next to the outline of a US quarter, which is 24.26 mm across, and to see which pearl types typically come in it. [2] - 2 mm - 4 mm - 6 mm - 8 mm - 10 mm - 12 mm - 14 mm - 16 mm - 18 mm - 20 mm Pearls from 2 to 20 mm across, drawn for Learn About Pearls. Without a scale setting they show at your screen's nominal size, which can differ from life size. | Pearl type | Typical size | Size range | | ------------------------- | ----------------------- | ------------------------------------------------------- | | Akoya cultured pearl | 6–8 mm [3, 4, 5, 6, 7] | 2–11 mm [3, 4, 5, 6, 7] | | Freshwater cultured pearl | 3–15 mm [6, 7] | 3–25 mm [6, 7] | | Keshi cultured pearl | Not recorded | under 1 mm to 16 mm (larger ones are very rare) [6, 8] | | South Sea cultured pearl | 9–16 mm [5, 6, 7] | 8–18 mm [5, 6, 7] | | Tahitian cultured pearl | 8–14 mm [5, 6, 7, 9] | 8–20 mm [5, 6, 7, 9] | ## Seeing true size on your screen Screens differ in how large they draw a millimeter, so the drawings may be larger or smaller than life until you set the scale. Open “Set the scale to life size” and move the slider until the bar measures 50 mm on a ruler, or until a US quarter laid on the circle just covers it. With JavaScript off you can still check: measure the 20 mm pearl with a ruler, and every drawing is off from life size by the same proportion. ## How pearls are measured CIBJO’s standards give a pearl’s measurements in millimeters, rounded down rather than up. A round pearl is measured across its widest diameter and, once [drilled](https://learnaboutpearls.com/glossary/#drilled), across the widest diameter at right angles to the drill hole. [1] The page [pearl size guide](https://learnaboutpearls.com/buying/pearl-size-guide/) explains how strands are measured and how to choose a size. ## Where the sizes come from The typical sizes and size ranges come from the Learn About Pearls dataset, and the numbers in the table point to each figure’s own sources. GIA cautions that pearls of every type can occur outside their typical ranges. [7] ## References 1. CIBJO, The World Jewellery Confederation, Pearl Commission (2026). The CIBJO Pearl Book (Pearl Blue Book) 2026. [Source](https://cibjo.org/wp-content/uploads/2026/10/Pearl-Blue-Book-2026-.pdf) · [Archived copy](https://web.archive.org/web/20261025235254/https://cibjo.org/wp-content/uploads/2026/10/Pearl-Blue-Book-2026-.pdf) 2. United States Mint. Coin Specifications. [Source](https://www.usmint.gov/learn/coins-and-medals/circulating-coins/coin-specifications) · [Archived copy](https://web.archive.org/web/20260927173844/https://www.usmint.gov/learn/coins-and-medals/circulating-coins/coin-specifications) 3. Areeya Manustrong (2018). Very Small Akoya Cultured Pearls. [Source](https://www.gia.edu/gems-gemology/spring-2018-gemnews-very-small-akoya-cultured-pearls) · [Archived copy](https://web.archive.org/web/20260508145843/https://www.gia.edu/gems-gemology/spring-2018-gemnews-very-small-akoya-cultured-pearls) 4. Artitaya Homkrajae (2024). Remarkably Large Akoya Bead Cultured Pearls. [Source](https://www.gia.edu/gems-gemology/summer-2024-gemnews-large-akoya-bead-cultured-pearls) · [Archived copy](https://web.archive.org/web/20261025235607/https://www.gia.edu/gems-gemology/summer-2024-gemnews-large-akoya-bead-cultured-pearls) 5. Fisheries Agency of Japan (水産庁) (2026). 真珠養殖をめぐる情勢について (On the situation of pearl culture). [Source](https://www.jfa.maff.go.jp/j/saibai/attach/pdf/shinju-60.pdf) · [Archived copy](https://web.archive.org/web/20261026000052/https://www.jfa.maff.go.jp/j/saibai/attach/pdf/shinju-60.pdf) 6. CIBJO Pearl Commission (2025). CIBJO Guides Describing and Classifying Natural and Cultured Pearls, the Producing Molluscs & Responsible Pearling. [Source](https://cibjo.org/wp-content/uploads/2025/12/Final-Guide-October-2025-v2-COMPRESSED.pdf) · [Archived copy](https://web.archive.org/web/20260212155210/https://cibjo.org/wp-content/uploads/2025/12/Final-Guide-October-2025-v2-COMPRESSED.pdf) 7. Gemological Institute of America (GIA), FAQ. What are the main types of cultured pearls and what are their distinctive characteristics?. [Source](https://www.gia.edu/FAQ/gia-faq-about-gemstones-cultured-pearl-types-characteristics) · [Archived copy](https://web.archive.org/web/20260510233833/https://www.gia.edu/FAQ/gia-faq-about-gemstones-cultured-pearl-types-characteristics) 8. H. A. Hänni (2006). A short review of the use of "keshi" as a term to describe pearls. [Source](https://www.ssef.ch/wp-content/uploads/2018/03/2006_Haenni_A_short_review_of_the_use_of_Keshi_as_a_term_to_describe_pearls.pdf) · DOI [10.15506/JoG.2006.30.1.51](https://doi.org/10.15506/JoG.2006.30.1.51) · [Archived copy](https://web.archive.org/web/20260416052623/https://www.ssef.ch/wp-content/uploads/2018/03/2006_Haenni_A_short_review_of_the_use_of_Keshi_as_a_term_to_describe_pearls.pdf) 9. Oïhana Latchere and others (2018). Influence of water temperature and food on the last stages of cultured pearl mineralization from the black-lip pearl oyster Pinctada margaritifera. [Source](https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0193863) · DOI [10.1371/journal.pone.0193863](https://doi.org/10.1371/journal.pone.0193863) · [Archived copy](https://web.archive.org/web/20260905233729/https://journals.plos.org/plosone/article?id=10.1371%2Fjournal.pone.0193863) **Written by:** Learn About Pearls editors **Fact-checked:** Learn About Pearls editors, October 26, 2026 **Reviewed by:** Simon, October 26, 2026 **First published:** November 4, 2026 **Publisher:** [Unique Pearl](https://learnaboutpearls.com/about/), a pearl jeweler **Revision history** 1. November 4, 2026: First published. First published **How to cite this page** **APA:** Learn About Pearls editors. (2026). _How Big Is a Pearl? See Pearl Sizes at True Size_. Learn About Pearls. https://learnaboutpearls.com/tools/pearl-size-visualizer/ **MLA:** “How Big Is a Pearl? See Pearl Sizes at True Size.” _Learn About Pearls_, Unique Pearl, November 4, 2026, learnaboutpearls.com/tools/pearl-size-visualizer/. **Chicago:** Learn About Pearls editors. “How Big Is a Pearl? See Pearl Sizes at True Size.” Learn About Pearls. Unique Pearl. Last modified November 4, 2026. https://learnaboutpearls.com/tools/pearl-size-visualizer/. **BibTeX:** `@misc{lap-tools-pearl-size-visualizer, title = {How Big Is a Pearl? See Pearl Sizes at True Size}, author = {{Learn About Pearls editors}}, year = {2026}, howpublished = {\url{https://learnaboutpearls.com/tools/pearl-size-visualizer/}}, note = {Learn About Pearls, published by Unique Pearl}}` Quoting with attribution and a link is welcome. See [how to cite and reuse](https://learnaboutpearls.com/cite/). **Suggest a correction** ## Related pages - [Pearl size guide](https://learnaboutpearls.com/buying/pearl-size-guide/): How pearls are measured, the usual sizes of each type, and how size affects value. - [Necklace length guide](https://learnaboutpearls.com/tools/necklace-length-guide/): Enter a length and see its standard name, from collar to rope. - [Pearl types](https://learnaboutpearls.com/types/): Akoya, freshwater, South Sea, Tahitian and keshi pearls, and where each one comes from.