@apollo/client
A fully-featured caching GraphQL client.
About
A fully-featured caching GraphQL client.
What detecting @apollo/client tells you about a site
@apollo/client reveals a GraphQL data layer with a normalised client-side cache — the app queries a GraphQL API and Apollo manages caching, optimistic updates and local state. Its presence is a strong signal of a GraphQL-first backend contract.
Why the exact @apollo/client version matters
Apollo Client's cache configuration and React hooks API evolved across v3's minor releases, and v4 is a larger shift. The exact version tells you which hook and cache API the code targets and how current the GraphQL tooling is.
@apollo/client in a real-world stack
When you find @apollo/client in a bundle, it rarely travels alone. graphql (always), and a framework like Next.js or a Vite SPA around it.
Quick facts
npm install @apollo/clientThis package powers Apollo
The @apollo/client package is the canonical implementation of Apollo. Sourcemap Explorer uses this exact npm package as the framework-level fingerprint when it flags Apollo on a page — both via the bundled node_modules/@apollo/client/ source paths and via the embedded package.json inside the JavaScript sourcemap.
Common pairings
Packages this one expects to find in the same project. Each is also a Sourcemap Explorer detection target.
What @apollo/client pulls in
@apollo/client declares 7 direct dependencies — each one also rides into any bundle that ships @apollo/client, so they are detection targets too. Reading them is a quick way to understand the package's real footprint .
How Sourcemap Explorer detects @apollo/client
@apollo/client ships as v4.2.9, published 2026-07-30 and carries 7 direct dependencies, 6 peer dependencies (rxjs, react, graphql), 712 versions on the registry. Those exact numbers are the footprint Sourcemap Explorer matches when @apollo/client rides inside a deployed bundle — here is how the detection works.
We catch @apollo/client from two complementary signals: bundled source paths and the embedded package.json. Modern bundlers (webpack, Vite, esbuild, Rollup, Turbopack) preserve the original node_modules/@apollo/client/ paths inside the JavaScript sourcemap's sources[] array — that's the canonical signal. When the matching package.json is also captured in sourcesContent[], we read the exact version field — patch number included. No regex guessing, no version inference.
- 1
Confirm the site exposes sourcemaps
In DevTools Network, check the response headers of any application script for `SourceMap` or `X-SourceMap`. Failing that, fetch the script's last 4 KB and look for a `//# sourceMappingURL=` comment — that map is where the `@apollo/client` paths live.
- 2
Find the package in the bundle
Open DevTools → Network → reload. Click any application script and look at its sourcemap. Inside, search `sources[]` for entries matching `node_modules/@apollo/client/` — every match confirms the package is bundled. The matching `sourcesContent[i]` for `node_modules/@apollo/client/package.json` gives you the exact installed version.
- 3
Read the version directly from package.json
Run `jq -r '. as $m | $m.sources | to_entries[] | select(.value | endswith("node_modules/@apollo/client/package.json")) | $m.sourcesContent[.key] | fromjson | .version' bundle.js.map`. Sourcemap Explorer automates the same query in the popup.
Major releases of @apollo/client
When each major version first landed. Major bumps are where breaking changes live, so this timeline is the fastest way to date the @apollo/client version a site actually ships against the ecosystem.
Recent versions
@apollo/client README
Live mirror of the GitHub README, for reference. Updated whenever the repo's default branch changes.
Apollo Client
Apollo Client is a fully-featured caching GraphQL client with integrations for React, Angular, and more. It allows you to easily build UI components that fetch data via GraphQL.
Documentation
All Apollo Client documentation, including React integration articles and helpful recipes, can be found at:
https://www.apollographql.com/docs/react/
The Apollo Client API reference can be found at:
https://www.apollographql.com/docs/react/api/apollo-client/
Maintainers
FAQ
What is @apollo/client used for?
A fully-featured caching GraphQL client.
How can I tell if a website is using @apollo/client?
Open the page in Chrome with the Sourcemap Explorer extension installed and read the Stack tab. We catch `@apollo/client` from two complementary signals: `node_modules/@apollo/client/` paths inside the JavaScript sourcemap, and the embedded `package.json` we read for exact-version detection. Without the extension you can do the same lookup manually in DevTools — the steps are listed in the "How Sourcemap Explorer detects" section above.
How do I find out which version of @apollo/client a website is running?
Read it straight from the site's JavaScript sourcemap. When a build ships source maps, the bundled `@apollo/client/package.json` carries the exact `version` string — Sourcemap Explorer extracts it in one click on the Stack tab, and you can do it by hand in DevTools by opening the `.map` file and searching for `node_modules/@apollo/client/package.json`. That is far more reliable than inferring the version from an asset-hash or a `?ver=` query string, which is all surface-level detectors have to go on. The current npm release is 4.2.9, but real deployments frequently run an older pinned version — which is exactly why reading the bundled number matters.
What is the latest version of @apollo/client?
4.2.9, as published on the npm registry. The "Recent versions" table on this page lists the most recent 8 releases with their release dates. Sourcemap Explorer reports the version actually bundled into a site, which can lag the latest release by months on real-world deployments.
Is @apollo/client actively maintained?
Very actively maintained — the last release shipped within the past three months. The last published release was 2026-07-30. Source code: https://github.com/apollographql/apollo-client.
What is the relationship between @apollo/client and Apollo?
@apollo/client is the canonical npm package for Apollo. Sourcemap Explorer treats finding `@apollo/client` in a bundle as the framework-level signal that Apollo is on the page, and the page you're reading is the canonical Sourcemap Explorer entry for the package itself.
Where can I read more?
Project homepage: https://www.apollographql.com/docs/react/. Source code: https://github.com/apollographql/apollo-client. Published on npm: https://www.npmjs.com/package/@apollo/client. Licensed as MIT.
Keep reading on Sourcemap Explorer
Detected by Sourcemap Explorer
When a bundle ships sourcemaps, we read the embedded package.json for @apollo/client and report the precise version (the registry's latest is v4.2.9, published 2026-07-30; the bundled copy is often older). Without sourcemaps, an import / require in the page's scripts is enough to flag it.