How to Delete PDF Pages Using JavaScript

In this post, you’ll learn how to delete PDF pages using our Delete PDF Page JavaScript API. With our API, you receive 100 credits with the free plan. Different operations on a document consume different amounts of credits, so the number of PDF documents you can generate may vary. You’ll just need to create a free account to access your API key.

This post will be especially helpful for developers working with JavaScript in document-heavy workflows who need to programmatically remove pages from a PDF to delete confidential data, save storage space, or remove information that’s unnecessary for end users.

PSPDFKit API

Deleting PDF pages is just one of the operations possible with our 30+ PDF API tools. You can combine our deletion tool with other tools to create complex document processing workflows, such as:

• Converting MS Office files and images into PDFs before removing pages

• Removing pages from two documents before merging them

• Deleting pages and then watermarking and flattening PDFs

Once you create your account, you’ll be able to access all our PDF API tools.

Step 1 — Creating a Free Account on PSPDFKit

Go to our website, where you’ll see the page below, prompting you to create your free account.

Once you’ve created your account, you’ll be welcomed by the page below, which shows an overview of your plan details.

As you can see in the bottom-left corner, you’ll start with 100 credits to process, and you’ll be able to access all our PDF API tools.

Step 2 — Obtaining the API Key

After you’ve verified your email, you can get your API key from the dashboard. In the menu on the left, click API Keys. You’ll see the following page, which is an overview of your keys:

Copy the Live API Key, because you’ll need this for the Delete PDF Page API.

Step 3 — Setting Up Folders and Files

Now, create a folder called delete_pdf and open it in a code editor. For this tutorial, you’ll use VS Code as your primary code editor. Next, create two folders inside delete_pdf and name them input_documents and processed_documents.

Then, in the root folder, delete_pdf, create a file called processor.js. This is where you’ll keep your code.

Your folder structure will look like this:

delete_pdf
├── input_documents
├── processed_documents
└── processor.js

Step 4 — Installing Dependencies

To get started deleting PDF pages, you first need to install the following dependencies:

• axios — This package is used for making REST API calls.

• Form-Data — This package is used for creating form data.

Use the command below to install both of them:

npm install axios
npm install form-data

Step 5 — Writing the Code

Now, open the processor.js file and paste the code below into it:

const axios = require('axios')
const FormData = require('form-data')
const fs = require('fs')

const formData = new FormData()
formData.append('instructions', JSON.stringify({
  parts: [
    {
      file: "document",
      pages: {
        end: 2
      }
    },
    {
      file: "document",
      pages: {
        start: 4
      }
    }
  ]
}))
formData.append('document', fs.createReadStream('input_documents/document.pdf'))

;(async () => {
  try {
    const response = await axios.post('https://api.pspdfkit.com/build', formData, {
      headers: formData.getHeaders({
          'Authorization': 'Bearer YOUR_API_KEY_HERE',
      }),
      responseType: "stream"
    })

    response.data.pipe(fs.createWriteStream("processed_documents/result_js.pdf"))
  } catch (e) {
    const errorString = await streamToString(e.response.data)
    console.log(errorString)
  }
})()

function streamToString(stream) {
  const chunks = []
  return new Promise((resolve, reject) => {
    stream.on("data", (chunk) => chunks.push(Buffer.from(chunk)))
    stream.on("error", (err) => reject(err))
    stream.on("end", () => resolve(Buffer.concat(chunks).toString("utf8")))
  })
}

ℹ️ Note: Make sure to replace YOUR_API_KEY_HERE with your API key.

Code Explanation

After importing all the required packages, you created a FormData object that contains all the instructions for the API to process. For this example, you deleted page number 4, but you can specify another page by replacing that number.

After that, you read the input document using the fs.createReadStream function.

Finally, you used axios to make the API call, and the response was stored in the processed_documents folder.

Output

To run the code, use the command below:

node processor.js

On the successful execution of the code, you’ll see a new processed file named result_js.pdf in the processed_documents folder.

The folder structure will look like this:

delete_pdf
├── input_documents
|    └── document.pdf
├── processed_documents
|    └── result_js.pdf
└── processor.js

Final Words

In this post, you learned how to easily and seamlessly delete pages from a PDF document for your JavaScript application using our Delete PDF Page API.

You can integrate our PDF API functions into your existing applications to remove pages from PDFs. With the same API token, you can also perform other operations, such as merging documents into a single PDF, adding watermarks, and more. To get started with a free trial, sign up here.