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Periodic Table of the Elements

Interactive periodic table with detailed information for all 118 chemical elements. Available in English, Swedish, Danish and Spanish. Each element page covers physical properties (atomic mass, density, melting/boiling point), atomic structure (electron configuration, shells, orbital diagram), classification (category, period, block, group), discovery history (who, when, naming origin), and external identifiers (CAS Number, ChemSpider ID, EC number, PubChem CID). The site also hosts six free int

For agents: Interactive periodic table with data on all 118 elements in four languages, plus a free JSON API, search API and machine-readable data.

periodic tablechemical elementselement datajson apiatomic properties

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The beginning of the file, from our validated copy saved 2026-10-23T16:54:32.974Z. Cached copy · Source on periodictable.one

# Periodic Table of the Elements

> Interactive periodic table with detailed information for all 118 chemical elements. Available in English, Swedish, Danish and Spanish. Each element page covers physical properties (atomic mass, density, melting/boiling point), atomic structure (electron configuration, shells, orbital diagram), classification (category, period, block, group), discovery history (who, when, naming origin), and external identifiers (CAS Number, ChemSpider ID, EC number, PubChem CID). The site also hosts six free interactive quizzes for memorising symbols, atomic numbers, categories and table layout.

Data is sourced from Wikipedia with attribution on each element page. Structured data is exposed via JSON-LD in every page's `<head>` for direct machine consumption.

## Machine-readable data

- [JSON API](https://www.periodictable.one/api/elements.json): all 118 elements with full data (physical properties, atomic structure, identifiers, discovery history, translations in all active languages). One single endpoint, no pagination, ~80 KB. Cached 1 hour. CORS-enabled.
- [Search API](https://www.periodictable.one/api/search.json?q=gold): typeahead lookup by name or symbol, JSON response.

## Sitemap

- [XML sitemap](https://www.periodictable.one/sitemap.xml): all URLs with `hreflang` alternates per language. Covers element pages, comparison pages, properties, history and the full quiz section.

## Core pages (English)

- [Home / Periodic table](https://www.periodictable.one/): interactive grid of all 118 elements
- [Chemical elements](https://www.periodictable.one/elements): all 118 elements with a stats banner, four view modes (Cards default, Compact mini-cards, sortable Table, alphabetical 3-column List), chip-style category filters, and a "Browse by" section linking the other filter dimensions. 41 filter sub-pages in total: nine categories (`/elements/nonmetals`, `/noble-gases`, `/alkali-metals`, `/alkaline-earth-metals`, `/metalloids`, `/post-transition-metals`, `/transition-metals`, `/lanthanides`, `/actinides`), three phases (`/elements/solid`, `/liquid`, `/gas`), seven periods (`/elements/period/1` … `/period/7`), eighteen groups (`/elements/group/1` … `/group/18`), and four blocks (`/elements/block/s`, `/p`, `/d`, `/f`). Each sub-page is its own indexable list with a heading, intro paragraph and the same four view modes.
- [Element detail](https://www.periodictable.one/element/1): full data for one element (replace `1` with any atomic number 1-118)
- [Compare elements](https://www.periodictable.one/compare): side-by-side comparison of two elements (URL pattern: `/compare/{element1}-vs-{element2}`)
- [Periodic table history](https://www.periodictable.one/history): timeline of discoveries, discoverers list, era-coloured periodic table and the name-origins explorer
- [Element name origins](https://www.periodictable.one/history/name-origins): visual periodic table coloured by name source (place, properties, person, mythology, astrono
…

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