> ## Documentation Index
> Fetch the complete documentation index at: https://algolia.com/llms.txt
> Use this file to discover all available pages before exploring further.

# What is InstantSearch.js?

> What is the InstantSearch.js UI library and what are the available customization APIs.

export const Index = () => <Tooltip tip="An Algolia index is a searchable dataset that consists of records and configuration settings. These settings define how the records are searched and ranked.">
    index
  </Tooltip>;

export const FlavorSwitcher = ({current, baseHref = "", options = [], label = "InstantSearch framework"}) => {
  if (options.length === 0) {
    return <div className="not-prose" role="alert" style={{
      margin: "0.25rem 0 1.5rem",
      padding: "0.75rem",
      border: "1px solid #f59e0b",
      borderRadius: "0.625rem",
      color: "inherit",
      fontSize: "0.875rem"
    }}>
        FlavorSwitcher requires at least one option.
      </div>;
  }
  const selected = options.find(option => option.value === current) ?? options[0];
  return <div className="not-prose mint-flavor-switcher">
      <style>{`
        .mint-flavor-switcher {
          --mfs-bg: #ffffff;
          --mfs-bg-hover: #f4f4f5;
          --mfs-bg-current: #eef2ff;
          --mfs-border: #d4d4d8;
          --mfs-fg: #18181b;
          --mfs-muted: #71717a;
          --mfs-accent: #4f46e5;
          position: relative;
          width: min(100%, 19rem);
          margin: 0.25rem 0 1.5rem;
          color: var(--mfs-fg);
          font-size: 0.875rem;
          line-height: 1.25rem;
        }

        .dark .mint-flavor-switcher {
          --mfs-bg: #18181b;
          --mfs-bg-hover: #27272a;
          --mfs-bg-current: #272747;
          --mfs-border: #3f3f46;
          --mfs-fg: #fafafa;
          --mfs-muted: #a1a1aa;
          --mfs-accent: #a5b4fc;
        }

        .mint-flavor-switcher details {
          position: relative;
        }

        .mint-flavor-switcher summary {
          display: flex;
          min-height: 2.75rem;
          box-sizing: border-box;
          align-items: center;
          justify-content: space-between;
          gap: 0.75rem;
          padding: 0.625rem 0.75rem;
          border: 1px solid var(--mfs-border);
          border-radius: 0.625rem;
          background: var(--mfs-bg);
          color: var(--mfs-fg);
          cursor: pointer;
          font-weight: 600;
          list-style: none;
          transition: border-color 150ms ease, box-shadow 150ms ease;
        }

        .mint-flavor-switcher summary::-webkit-details-marker {
          display: none;
        }

        .mint-flavor-switcher summary:hover {
          border-color: var(--mfs-accent);
        }

        .mint-flavor-switcher summary:focus-visible {
          outline: 2px solid var(--mfs-accent);
          outline-offset: 2px;
        }

        .mint-flavor-switcher__label {
          overflow: hidden;
          text-overflow: ellipsis;
          white-space: nowrap;
        }

        .mint-flavor-switcher__chevron {
          flex: none;
          transition: transform 150ms ease;
        }

        .mint-flavor-switcher details[open] .mint-flavor-switcher__chevron {
          transform: rotate(180deg);
        }

        .mint-flavor-switcher__menu {
          position: absolute;
          z-index: 50;
          top: calc(100% + 0.375rem);
          left: 0;
          width: 100%;
          box-sizing: border-box;
          margin: 0;
          padding: 0.375rem;
          border: 1px solid var(--mfs-border);
          border-radius: 0.625rem;
          background: var(--mfs-bg);
          box-shadow: 0 12px 30px rgb(0 0 0 / 16%);
          list-style: none;
        }

        .mint-flavor-switcher__menu li {
          margin: 0;
          padding: 0;
        }

        .mint-flavor-switcher__option {
          display: grid;
          gap: 0.125rem;
          padding: 0.625rem 0.75rem;
          border-radius: 0.4rem;
          color: var(--mfs-fg);
          text-decoration: none;
        }

        .mint-flavor-switcher__option:hover {
          background: var(--mfs-bg-hover);
        }

        .mint-flavor-switcher__option:focus-visible {
          outline: 2px solid var(--mfs-accent);
          outline-offset: -2px;
        }

        .mint-flavor-switcher__option[aria-current="page"] {
          background: var(--mfs-bg-current);
          color: var(--mfs-accent);
        }

        .mint-flavor-switcher__name {
          font-weight: 600;
        }

        .mint-flavor-switcher__description {
          color: var(--mfs-muted);
          font-size: 0.8125rem;
        }

        @media (prefers-reduced-motion: reduce) {
          .mint-flavor-switcher summary,
          .mint-flavor-switcher__chevron {
            transition: none;
          }
        }
      `}</style>

      <details>
        <summary aria-label={`${label}: ${selected.label}`}>
          <span className="mint-flavor-switcher__label">{selected.label}</span>
          <svg className="mint-flavor-switcher__chevron" width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true">
            <path d="m6 9 6 6 6-6" />
          </svg>
        </summary>

        <ul className="mint-flavor-switcher__menu" aria-label={label}>
          {options.map(option => {
    const isCurrent = option.value === selected.value;
    const href = option.href ?? `${baseHref.replace(/\/$/, "")}/${encodeURIComponent(option.value)}`;
    return <li key={option.value}>
                <a className="mint-flavor-switcher__option" href={href} aria-current={isCurrent ? "page" : undefined}>
                  <span className="mint-flavor-switcher__name">
                    {option.label}
                  </span>
                  {option.description ? <span className="mint-flavor-switcher__description">
                      {option.description}
                    </span> : null}
                </a>
              </li>;
  })}
        </ul>
      </details>
    </div>;
};

<div className="mint-flavor-switcher-slot not-prose">
  <FlavorSwitcher
    current="js"
    baseHref="/doc/guides/building-search-ui/what-is-instantsearch"
    options={[
{ value: "js", label: "JavaScript", description: "InstantSearch.js" },
{ value: "react", label: "React", description: "React InstantSearch" },
{ value: "vue", label: "Vue", description: "Vue InstantSearch" },
{ value: "ios", label: "iOS", description: "InstantSearch iOS" },
{ value: "android", label: "Android", description: "InstantSearch Android" },
{ value: "flutter", label: "Flutter", description: "Algolia for Flutter" },
]}
  />
</div>

{/* vale Google.WordList = NO */}

InstantSearch.js is an open source UI library for vanilla JS that lets you build a search interface in your frontend app.

InstantSearch focuses on enhancing your frontend with widgets that you can combine to create unique search interfaces.

<Card title="Open CodeSandbox" icon="box" href="https://codesandbox.io/embed/github/algolia/instantsearch/tree/master/examples/js/getting-started">
  Run and edit the What is InstantSearch.js? example in CodeSandbox.
</Card>

<Frame>
  <iframe width="644" height="362" className="video-embed" src="https://www.youtube.com/embed/ki4CyaTUoPo?start=1355" title="Integrate a search experience into a vanilla JavaScript storefront with Algolia - Dhaya Benmessaoud" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" referrerpolicy="strict-origin-when-cross-origin" allowfullscreen />
</Frame>

InstantSearch offers three levels of increasing control over your UI:

1. Start with a **predefined widget** that you can configure and style with CSS.
2. To change its render output (DOM or Native), **customize a predefined widget** to render what you want.
3. To implement something that doesn't exist, create a **custom widget**.

## Predefined widgets

The recommended way to use InstantSearch is with its predefined widgets such as [`searchBox`](/doc/api-reference/widgets/search-box/js).
InstantSearch includes a [set of widgets](/doc/guides/building-search-ui/widgets/showcase/js) that are most often used in search experiences.
Widgets provide features and a rendered output.
You can place them anywhere on your UI, configure them, and style them with CSS.

For example, add the [`refinementList`](/doc/api-reference/widgets/refinement-list/js)\` widget and ask it to show a list of brands,
so your users can refine their search using those brands.

```js JavaScript icon=code theme={"system"}
instantsearch.widgets.refinementList({
  container: document.querySelector("#brand"),
  attribute: "brand",
});
```

### The InstantSearch wrapper

The [`instantsearch`](/doc/api-reference/widgets/instantsearch/js) wrapper communicates between your app and Algolia.
This is where you add all the widgets.
It accepts a search client and an <Index /> name.

```js JavaScript icon=code theme={"system"}
const searchClient = algoliasearch(
  "latency",
  "6be0576ff61c053d5f9a3225e2a90f76",
);

const search = instantsearch({
  indexName: "INDEX_NAME",
  searchClient,
});

search.addWidgets([
  instantsearch.widgets.refinementList({
    container: document.querySelector("#brand"),
    attribute: "brand",
  }),
]);
```

Once you've added all the desired widgets to the wrapper, call the `start` method to begin searching:

```js JavaScript icon=code theme={"system"}
search.start();
```

### CSS theme

The predefined widgets in InstantSearch.js are compatible with the default CSS theme:

<img src="https://mintcdn.com/algolia/PPYT_t3uPKSP6jma/images/instantsearch/common/what-is-instantsearch/theme-preview.png?fit=max&auto=format&n=PPYT_t3uPKSP6jma&q=85&s=ab062f696477da133dcdf6a482afddf5" alt="Screenshot of a search results page with product cards, a 'Category: Movies and TV Shows' filter, and a pagination bar." width="930" height="560" data-path="images/instantsearch/common/what-is-instantsearch/theme-preview.png" />

For more information, see [Style your widgets](/doc/guides/building-search-ui/widgets/customize-an-existing-widget/js#style-your-widgets).

## Customize widgets

Algolia's predefined widgets, with their fixed behavior and output, may not fully meet your requirements.
For example, you might want to customize the rendering of the [`menu`](/doc/api-reference/widgets/menu/js) widget to display as a [`select`](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/select) element instead of a list of links. You may also want to render it as a keyboard-controlled slideshow of images.

To address these limitations, InstantSearch.js uses *connectors* to redefine widget behavior and DOM output.

For more information, see [Customize an InstantSearch.js widget](/doc/guides/building-search-ui/widgets/customize-an-existing-widget/js).

## Custom widgets

If none of the previous solutions work for you and you want to create a new widget from scratch,
InstantSearch provides a third API layer of API for this: **creating custom widgets**.
This requires two APIs: the first one lets you create a new connector, and the second one lets you create a new widget.
Both solutions give you full control of the render and behavior.

When building a new widget, be prepared to dive deep into the Algolia semantics to achieve what you want.

For more information, see [Create your own InstantSearch.js widgets](/doc/guides/building-search-ui/widgets/create-your-own-widgets/js).

## Resources

Use the following links and resources to learn more.

### See also

* [Install InstantSearch.js](/doc/guides/building-search-ui/installation/js)
* [Get started](/doc/guides/building-search-ui/getting-started/js)
* [API reference](/doc/api-reference/widgets/js)
* [Code Exchange](https://www.algolia.com/developers/code-exchange/?category=frontend-tools)
* [Support knowledge base](https://support.algolia.com/hc/en-us/sections/4406469041041-InstantSearch-InstantSearch-js)

### Join the community

Ask questions and find answers on the following platforms:

* [Algolia Community Discord](https://alg.li/discord)
* [Stack Overflow](https://stackoverflow.com/questions/tagged/instantsearch)
* [GitHub issues](https://github.com/algolia/instantsearch/issues)
* [Changelog](https://github.com/algolia/instantsearch/blob/master/packages/instantsearch.js/CHANGELOG.md)