Next.js Image Loader and Component

Optimize images with Uploadcare on the fly by using the UploadcareImage component or the uploadcareLoader custom image loader for Next.js.

The built-in Next.js Image component does a great job in optimizing images but the number of optimizations is limited. It allows setting a custom image loader to process images externally. This is where the @uploadcare/nextjs-loader package comes in handy.

GitHub →

Here is a demo app and its source code.

Features

• Optimize image characteristics (quality, resolution, format, and others) with an extended list of Uploadcare image processing operations.
• Load the optimized images through Uploadcare CDN.

Installation

yarn add @uploadcare/nextjs-loader

Configuration

Get your public key from the Dashboard and add it to your environment variables through .env file or your hosting UI.

1
# .env
2
NEXT_PUBLIC_UPLOADCARE_PUBLIC_KEY="YOUR_PUBLIC_KEY"

If you’re using a proxy, provide your application’s base URL (also whitelisted), which is required to process local images properly.

1
# .env
2
NEXT_PUBLIC_UPLOADCARE_APP_BASE_URL="https://your-domain.com/"

Image transformation settings example:

1
# .env
2
NEXT_PUBLIC_UPLOADCARE_TRANSFORMATION_PARAMETERS="quality/lightest, stretch/off, progressive/yes"

The default image transformation parameters are stretch/off, progressive/yes.

Find additional settings, such as custom CDN domain, and custom proxy domain, in the developer documentation on Github.

Usage

Allow custom image loaders through next.config.js:

1
// next.config.js
2
module.exports = {
3
  images: {
4
    loader: "custom"
5
  }
6
}

The easiest and the most straightforward way of utilizing the power of Uploadcare is to use the UploadcareImage component for all images on your site the same way as the built-in Image component.

1
import UploadcareImage from '@uploadcare/nextjs-loader';
2
3
<UploadcareImage
4
  alt="A test image"
5
  src="https://your-domain/image.jpg"
6
  width="400"
7
  height="300"
8
/>

If you still need to use the built-in Image component with the uploadcareLoader:

1
import Image from 'next/image';
2
import { uploadcareLoader } from '@uploadcare/nextjs-loader';
3
4
<Image
5
  alt="A test image"
6
  src="https://your-domain/image.jpg"
7
  width="400"
8
  height="300"
9
  loader={uploadcareLoader}
10
/>

Note that if you pass a local image URL, the loader returns it AS IS if the app is run in the development mode or if the NEXT_PUBLIC_UPLOADCARE_APP_BASE_URL is not set.

Full documentation

Read the full documentation on GitHub.