Title: Branching Software Chemical Structure Search for WooCommerce Author: Branching Software Published: October 5, 2026 Last modified: October 5, 2026 --- Search plugins ![](https://ps.w.org/branching-software-chemical-search/assets/banner-772x250.png? rev=3728061) ![](https://ps.w.org/branching-software-chemical-search/assets/icon-256x256.png? rev=3728061) # Branching Software Chemical Structure Search for WooCommerce By [Branching Software](https://profiles.wordpress.org/branchingsoftware/) [Download](https://downloads.wordpress.org/plugin/branching-software-chemical-search.1.0.0.zip) * [Details](https://wordpress.org/plugins/branching-software-chemical-search/#description) * [Reviews](https://wordpress.org/plugins/branching-software-chemical-search/#reviews) * [Installation](https://wordpress.org/plugins/branching-software-chemical-search/#installation) * [Development](https://wordpress.org/plugins/branching-software-chemical-search/#developers) [Support](https://wordpress.org/support/plugin/branching-software-chemical-search/) ## Description Your catalog is searchable by name and CAS number, which works right up until the buyer knows neither. They know the structure. This lets them draw it. A shopper clicks a button, draws a molecule, and gets back the products in your catalog that match — either the same substance, or every product containing what they drew. Draw a benzene ring and you get everything with a benzene ring in it. Results are rendered with **your theme’s own product template**, so they look like the rest of your shop: your prices, your badges, your add-to-cart buttons. #### Who it is for Any WooCommerce store that sells by structure: chemical suppliers and distributors, reagent and laboratory supply shops, building-block and screening-compound vendors, custom synthesis and research chemical sellers, fine chemical and pharmaceutical intermediate catalogs. If your buyers think in molecules, SMILES strings and CAS numbers, this gives them a search box that speaks their language: chemical structure search, substructure search, SMILES search, CAS number lookup and plain product name search, all in one drawer on your product pages. #### What it does * **Exact structure search.** Finds the same molecule however it was drawn or written. Caffeine drawn three different ways finds caffeine all three times — and does not find theobromine, which is one methyl group away. * **Substructure search.** Finds every product containing the drawn fragment. * **Similarity search.** A checkbox that also returns the products closest to what was drawn, each scored, so a buyer who cannot find the exact compound is shown the nearest thing you do stock. * **A drawing editor** built into your storefront (JSME, by Peter Ertl and Bruno Bienfait). * **Chemistry fields on every product:** SMILES, CAS number, molecular formula, molecular weight — shown on the product page in your theme’s own styling. * **Structure images** drawn automatically and saved as files. * **CSV import** that accepts the column names your supplier already uses. * **A block and a shortcode**, so search goes wherever you want it. #### It does not slow your site down The chemistry toolkit is large — around 10 MB between the structure editor and the chemistry engine — and none of it is downloaded until a shopper actually clicks to open the drawing editor. A page with the search widget on it costs about 11 KB of JavaScript. A page without one costs nothing at all: no scripts, no styles, no requests. Searching happens in the shopper’s browser against a small index file, so it puts no load on your database however many people are searching at once. #### Accurate chemistry Matching is done by [RDKit](https://www.rdkit.org/), the standard open-source cheminformatics toolkit, compiled to WebAssembly. The same code canonicalises your catalog when you build the index and canonicalises what the shopper draws, so the two are always comparable. Aromaticity, tautomers, salts, stereochemistry and isotopes are handled by RDKit rather than by string matching — deuterated solvents stay distinct from their ordinary counterparts. #### Pro version Everything described on this page is in this plugin and stays free. A separate Pro add-on, sold by Branching Software, adds tools for keeping a catalog’s structures complete and for seeing what shoppers want: * **CAS to structure enrichment** — products with a CAS number and no structure are looked up on PubChem in the background, and you approve each suggestion before it is saved. * **SDF import** — upload a supplier’s SDF, map its fields to SKU or CAS, preview exactly what will change, then import. * **Search demand report** — the full report over the searches this plugin already records: every structure and query, filters, a daily trend, CSV export and a retention setting. The add-on installs as a second plugin and adds its tabs to this plugin’s screen. See https://branchingsoftware.com/chemical-structure-search/. ### Third-party libraries This plugin bundles two open-source libraries, both redistributed under their own terms with their licence files included: * **RDKit** (`assets/vendor/rdkit`), the cheminformatics toolkit that performs all structure matching, compiled to WebAssembly. BSD 3-Clause. https://www.rdkit. org/ — source: https://github.com/rdkit/rdkit-js * **JSME Molecule Editor** (`assets/vendor/jsme`), the structure drawing editor, by Peter Ertl and Bruno Bienfait. BSD 3-Clause. https://jsme-editor.github.io/— source: https://github.com/jsme-editor/jsme-editor.github.io Neither library contacts any external service. Both run entirely in the visitor’s browser, and this plugin makes no outbound requests of its own. ## Screenshots [⌊Storefront – the search drawer: draw a structure, or type a SMILES, InChI, CAS number, catalog number or product name.⌉⌊Storefront – the search drawer: draw a structure, or type a SMILES, InChI, CAS number, catalog number or product name.⌉[ Storefront – the search drawer: draw a structure, or type a SMILES, InChI, CAS number, catalog number or product name. [⌊Storefront – results: matching products rendered by the store's own theme, exact matches first, then everything containing the drawn structure.⌉⌊Storefront – results: matching products rendered by the store's own theme, exact matches first, then everything containing the drawn structure.⌉[ Storefront – results: matching products rendered by the store’s own theme, exact matches first, then everything containing the drawn structure. [⌊WooCommerce → Structure Search – Index tab: build the structure index in the browser and see the last 30 days of search activity.⌉⌊WooCommerce → Structure Search – Index tab: build the structure index in the browser and see the last 30 days of search activity.⌉[ WooCommerce Structure Search – Index tab: build the structure index in the browser and see the last 30 days of search activity. [⌊WooCommerce → Structure Search – Import tab: CSV import that accepts the column names suppliers already use.⌉⌊WooCommerce → Structure Search – Import tab: CSV import that accepts the column names suppliers already use.⌉[ WooCommerce Structure Search – Import tab: CSV import that accepts the column names suppliers already use. [⌊Product edit screen – Chemistry tab: SMILES, CAS number, molecular formula and molecular weight on every product.⌉⌊Product edit screen – Chemistry tab: SMILES, CAS number, molecular formula and molecular weight on every product.⌉[ Product edit screen – Chemistry tab: SMILES, CAS number, molecular formula and molecular weight on every product. [⌊Product page – the structure drawing and identifiers, shown in the theme's own styling.⌉⌊Product page – the structure drawing and identifiers, shown in the theme's own styling.⌉[ Product page – the structure drawing and identifiers, shown in the theme’s own styling. ## Blocks This plugin provides 1 block. * Chemical Structure Search Let shoppers draw a chemical structure and find the products that match it. ## Installation 1. Install and activate the plugin. WooCommerce 9.0 or newer must be active. 2. Add SMILES structures to your products — on each product’s **Chemistry** tab, or in bulk under **WooCommerce Structure Search Import**. 3. Go to **WooCommerce Structure Search** and click **Build index**. Leave the tab open while it runs; the chemistry runs in your browser. 4. Add the **Chemical Structure Search** block to a page, or use the shortcode [chemical_structure_search]. Rebuild the index after changing product structures. The admin screen tells you when it has drifted. #### Starting open By default the page shows a button and the drawing editor opens when a shopper clicks it, so nothing chemistry-sized downloads until they do. For a page that exists for structure search, turn on the block’s **Start open** toggle, or use [chemical_structure_search open=”yes”]: the editor is shown immediately with no button. The button and heading text are the block’s **Button text** and **Heading** fields, or `button="..."` and` heading="..."` on the shortcode. #### Typing instead of drawing The drawer also has one typed box. A SMILES or InChI is matched by chemistry, exactly as a drawing would be, and appears in the editor so it can be adjusted. A CAS number, a catalog number or a product name is looked up in the store’s own product data, which means it also finds products that have a CAS number but no structure yet, and works before the index has been built. #### Sizing and layout The drawing editor fills whatever width it is given. In the block editor, use the block’s alignment control to make it wide or full width; the shortcode takes `width ="wide"` or `width="full"` for the same thing. With room to spare, the search controls move into a column beside the editor. Results are laid out in a grid of your theme’s product cards. The block’s **Results layout** panel, or these shortcode attributes, control it: * `columns="3"` — a fixed number of columns, 1 to 6. The default, `0`, fits as many as the space allows. Small screens always get fewer. * `layout="list"` — one product per row, thumbnail on the left. * `limit="200"` — the most substructure matches one search will find. Exact matches are always found. Results arrive forty at a time behind a “Load more” button however high this is set, so raising it costs the store nothing per request. For example: `[chemical_structure_search width="wide" columns="4"]`. #### Colours **WooCommerce Structure Search Appearance** sets the accent colour, panel background, text colour and corner radius, with a live preview and your theme’s palette in the picker. Button text switches between white and dark on its own so a pale accent stays legible. The block has its own accent setting for one search that should differ, and the shortcode takes accent=”#b4532a”. Beyond that, every colour and size in the drawer is a CSS custom property a theme can override on `.chemsearch`. ## FAQ ### What is SMILES? A line notation for chemical structures — `CN1C=NC2=C1C(=O)N(C(=O)N2C)C` is caffeine. Most catalog systems and suppliers can export it, and PubChem lists it for any compound. It is the one field structure search actually needs. ### Do I have to get the SMILES exactly right? No. Any valid way of writing a structure works, because RDKit converts every one to a single canonical form before comparing. You do not have to match how anyone else wrote it. ### Why do I have to build an index? So that searching is instant and costs your server nothing. The index is one file, built once, that shoppers download and search against in their own browser. ### Why does the index build happen in my browser? The chemistry toolkit is WebAssembly. Running it needs a browser or a Node process, and a WordPress host has neither. Building it in your browser also means your catalog is canonicalised by exactly the same code that will later match against it — which is what makes exact search reliable. ### How big a catalog does this handle? Comfortably into the low thousands of products. Beyond about 10 000 the index file becomes large enough that it should be split into parts, which this version does not do yet. ### Will it work with my theme? Results are rendered by your theme’s own product template, so if your shop page looks right, results will too. ### Does it send my catalog anywhere? No. Everything runs on your site and in your shoppers’ browsers. The plugin makes no outbound requests at all. ### Which products end up in the public index? Only products a shopper could reach by browsing: published, not password-protected, and with catalog visibility “Shop and search results”. Hidden, draft, private and password-protected products are left out of the index file and are never rendered by the results endpoint, whatever a request asks for. Changing a product’s visibility marks the index as needing a rebuild. ### What does the search log store? Each search stores what was asked — the drawn or typed structure as canonical SMILES, or the CAS number, catalog number or name that was typed — and how many products matched, to the hour, and nothing about who searched: no IP address, account, cookie or browser details. The same visitor repeating the same search within an hour is recorded once. Rows are deleted after the retention period (default 90 days), the table is capped in size, and a suggested privacy-policy paragraph is added under Settings Privacy Policy Guide. The Index tab shows the last 30 days: how many searches, by structure or by name, how many found nothing, and the five most-wanted things the catalog does not have. ### Can someone overload the search endpoint? Each client gets a budget of thirty searches at once and thirty a minute after that, and one request renders at most forty product cards. A search that matches more sends the rest a page at a time behind a “Load more” button, so no single request can ask the store to build more than forty cards however many products matched. Both are filterable (`bscs_results_rate_limit`, bscs_max_results) for stores that need more. ### What happens when I uninstall? Deleting the plugin removes its settings, the search log table, its scheduled tasks and the index files it wrote to the uploads folder. The chemistry fields on your products (SMILES, CAS number, formula, weight) are left in place, because they are your catalog data and you may install the plugin again or export them. ### How does the CSV import work? Each row is matched to a product by SKU. A matching product is updated; a row with a new SKU creates a simple product. The file only changes the columns it carries: a SKU and SMILES file refreshes structures and leaves CAS numbers, formulas, weights, names and prices as they were. The column names your supplier uses are accepted ( CAS No, Catalog Number, Mol Weight and so on). After an import the admin screen asks for an index rebuild, since searching reads the index, not the products. ### What about variable products? Structures are set on the parent product, and the parent is what search returns. Per-variation structures are not supported. ## Reviews There are no reviews for this plugin. ## Contributors & Developers “Branching Software Chemical Structure Search for WooCommerce” is open source software. The following people have contributed to this plugin. Contributors * [ Branching Software ](https://profiles.wordpress.org/branchingsoftware/) [Translate “Branching Software Chemical Structure Search for WooCommerce” into your language.](https://translate.wordpress.org/projects/wp-plugins/branching-software-chemical-search) ### Interested in development? [Browse the code](https://plugins.trac.wordpress.org/browser/branching-software-chemical-search/), check out the [SVN repository](https://plugins.svn.wordpress.org/branching-software-chemical-search/), or subscribe to the [development log](https://plugins.trac.wordpress.org/log/branching-software-chemical-search/) by [RSS](https://plugins.trac.wordpress.org/log/branching-software-chemical-search/?limit=100&mode=stop_on_copy&format=rss). ## Changelog #### 1.0.0 * First public release on wordpress.org. * Exact, substructure and similarity search, matched by RDKit in the shopper’s browser against an index built in the admin. Nothing is sent anywhere. * A drawing editor (JSME) in a drawer that opens on click or, with the block’s** Start open** toggle or `open="yes"`, is shown immediately. * One typed box: SMILES and InChI go to the chemistry engine; CAS numbers, catalog numbers and product names are looked up in your own product data. * Results rendered through your theme’s product loop, in a grid or list, 1 to 6 columns, wide or full width. * Chemistry fields on every product (SMILES, CAS, formula, weight), a Chemistry tab on the product page, and a structure image per product. * CSV import that accepts supplier column names. * Appearance tab: accent, panel and text colours and corner radius, with your theme’s palette in the picker. The block and shortcode take an `accent`. * Search activity for the last 30 days on the admin screen, recorded with no personal data and purged after the retention period. * Rate-limited public endpoints that only ever return products a shopper could reach by browsing. ## Meta * Version **1.0.0** * Last updated **21 hours ago** * Active installations **Fewer than 10** * WordPress version ** 6.5 or higher ** * Tested up to **7.1.2** * PHP version ** 7.4 or higher ** * Tags * [chemistry](https://wordpress.org/plugins/tags/chemistry/)[smiles](https://wordpress.org/plugins/tags/smiles/) * [Advanced View](https://wordpress.org/plugins/branching-software-chemical-search/advanced/) ## Ratings No reviews have been submitted yet. [Your review](https://wordpress.org/support/plugin/branching-software-chemical-search/reviews/#new-post) [See all reviews](https://wordpress.org/support/plugin/branching-software-chemical-search/reviews/) ## Contributors * [ Branching Software ](https://profiles.wordpress.org/branchingsoftware/) ## Support Got something to say? Need help? [View support forum](https://wordpress.org/support/plugin/branching-software-chemical-search/)