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Use Cypress Component Testing to mount and check an individual React component in a browser; use end-to-end (E2E) tests for Next.js pages whose behavior depends on server-side execution. For Cypress 16, the documented Next.js compatibility floor is Next.js 15.0.4, or Next.js 16. Start with Cypress’s Launchpad, then configure the Next.js component dev server and write a mount-and-assert test.
Check compatibility and set up component testing
Cypress documents React Component Testing with Next.js 15 and 16. The release-specific boundary matters: Cypress 16.0.0 and later require Next.js 15.0.4 or newer, or Next.js 16; Next.js 14 is no longer supported for component testing under that guidance. Check the migration guide for the Cypress version you have installed if you are on a different release.
- Open Cypress and choose its Component Testing setup flow in Launchpad. Cypress says Launchpad detects the framework and bundler and scaffolds a configuration file.
- Confirm the component configuration in
cypress.config.jsorcypress.config.ts. The Next.js setup uses the Next framework and Webpack bundler:
import { defineConfig } from 'cypress'
export default defineConfig({
component: {
devServer: {
framework: 'next',
bundler: 'webpack',
},
},
})This configures a development server that compiles and serves component specs while Cypress runs; it is not a test against the production website. The server shuts down when the Cypress app closes or a run finishes. See Cypress’s component framework configuration for the general configuration model and framework details.
Write a first component test
A component test mounts a component directly in a real browser. Import the component, render it with the props the test needs, and assert a visible result. This illustrative example follows Cypress’s documented React pattern; adapt the import, prop names, and selector to your application.
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describe('Stepper', () => {
it('renders its initial count', () => {
cy.mount(<Stepper initial={2} />)
cy.get('[data-cy=counter]').should('have.text', '2')
})
})The data-cy attribute is a stable test selector in this example. If a component needs context, a provider, or other application setup, supply those dependencies through the test harness. A component test does not automatically recreate the entire Next.js runtime. Cypress’s getting-started guide and React examples show the mounting and assertion pattern.
Load global styles in component tests
To apply the app’s global CSS, Cypress’s Next.js styling guidance calls for a marker in the component index HTML’s <head> so Next.js can inject CSS:
<div id="__next_css__DO_NOT_USE__"></div>Import the application stylesheet from the component support file, commonly cypress/support/component.js. Use your project’s actual stylesheet path:
import '../../src/index.css'If global styles do not appear or mounting fails, check that the marker is present and the support-file import points to the correct stylesheet. See Cypress’s component styling guidance.
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Use component tests for isolated UI behavior: rendered output and interactions when the component is mounted with its required inputs and dependencies. Use E2E tests when the question concerns a complete page or flow that relies on Next.js server behavior.
| Test type | Scope | Execution context | Best fit |
|---|---|---|---|
| Component | An individual component | Mounted in Cypress’s component development server in a browser | Checking component output and interactions with supplied props and dependencies |
| End-to-end | A full page or user flow | Exercises the application and its server-side page behavior | Checking page behavior that depends on server execution |
In particular, getServerSideProps and getStaticProps are server-only methods; they do not run in a component test. A page depending on either can therefore receive undefined props when mounted this way. Cypress recommends: “Because of this, we recommend using E2E Testing over Component Testing for Next.js pages and Component Testing for individual components in a Next.js app.” That is Cypress’s guidance in its React Component Testing documentation, not a claim that component tests validate server-rendered behavior.
Troubleshoot common setup problems
- Cypress rejects the Next.js version: compare the installed versions with the Cypress release-specific compatibility boundary. Cypress 16 requires Next.js 15.0.4 or newer, or Next.js 16; Next.js 14 is unsupported for component testing in that release context.
- The component dev server does not start: check that
component.devServer.frameworkis'next'andcomponent.devServer.bundleris'webpack', and review the configuration guidance for your installed Cypress version. - Global CSS is missing or mounting fails: verify the
__next_css__DO_NOT_USE__marker in the component index HTML and confirm the stylesheet import in the component support file resolves to the right file. - A page test has undefined props: if those props come from
getServerSidePropsorgetStaticProps, move that page-level check to E2E testing. Keep component tests focused on components mounted with explicit inputs. - A mounted component fails because of missing context: provide the providers or other dependencies the component requires in the test harness; mounting an isolated component does not supply the full app environment.
Or skip the browser setup
If your task is to capture a website screenshot rather than test a React component, ScreenshotNeo offers a one-request screenshot API. This is not a replacement for Cypress component tests: it captures a URL, not an isolated component’s behavior.
Quick Recap
curl -G "https://api.screenshotneo.com/v1/shot" -d access_key=YOUR_API_KEY --data-urlencode url=https://stripe.com -o shot.webpSee the ScreenshotNeo API documentation for request options. ScreenshotNeo removes cookie banners, newsletter popups, and chat widgets before capture; bot checks, blank pages, and failed loads are never billed. Its MCP server lets AI agents take screenshots. The free plan includes 1,000 screenshots a month with no card, and paid plans start at $5 for 3,000. Sign up for the free plan.
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