Merge Split Delete Flatten Duplicate

Duplicate PDF Page C# API

Make a copy of one or more pages in a PDF document using our C# PDF page duplication API.

Flexible page duplication

Select specific pages or page ranges to duplicate and insert them wherever needed in a document. Great for duplicating signature pages, instructions, or templates.

Streamline complex workflows

Automate duplication tasks in large PDFs without manual editing. Perfect for applications like contracts, reports, or forms with repeatable content.

Simple and transparent pricing

Select a package that suits your needs according to the number of credits you wish to spend. Each API tool and action has a specific credit cost.

Nutrient is used by

Try it out

This example duplicates the first and last pages of a document.

Use Your Free API Calls

Sign up and receive 100 credits for free, or log in to automatically add your API key to sample code. If you are not sure how credits are consumed read more in our pricing documentation , or check out this guide on calculating credit usage.

Add a File

Add a PDF named document.pdf to your project folder. You can also use our sample file. The file name is case sensitive. Make sure the file name matches the file name in the sample code.

Run the Code

Copy the code and run it from the same folder you added the files to. For more information, see our language-specific getting started guides.

View the Results

Open result.pdf in your project folder to view the results.

Shell Shell (Windows) Java C# JavaScript Python PHP HTTP

curl -X POST https://api.nutrient.io/build \
  -H "Authorization: Bearer your_api_key_here" \
  -o result.pdf \
  --fail \
  -F document=@document.pdf \
  -F instructions='{
      "parts": [
        {
          "file": "document",
          "pages": {
            "start": 0,
            "end": 0
          }
        },
        {
          "file": "document"
        },
        {
          "file": "document",
          "pages": {
            "start": -1,
            "end": -1
          }
        }
      ]
    }'

curl -X POST https://api.nutrient.io/build ^
  -H "Authorization: Bearer your_api_key_here" ^
  -o result.pdf ^
  --fail ^
  -F document=@document.pdf ^
  -F instructions="{\"parts\": [{\"file\": \"document\", \"pages\": {\"start\": 0, \"end\": 0}}, {\"file\": \"document\"}, {\"file\": \"document\", \"pages\": {\"start\": -1, \"end\": -1}}]}"

package com.example.pspdfkit;

import java.io.File;
import java.io.IOException;
import java.nio.file.FileSystems;
import java.nio.file.Files;
import java.nio.file.StandardCopyOption;

import org.json.JSONArray;
import org.json.JSONObject;

import okhttp3.MediaType;
import okhttp3.MultipartBody;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.RequestBody;
import okhttp3.Response;

public final class PspdfkitApiExample {
  public static void main(final String[] args) throws IOException {
    final RequestBody body = new MultipartBody.Builder()
      .setType(MultipartBody.FORM)
      .addFormDataPart(
        "document",
        "document.pdf",
        RequestBody.create(
          MediaType.parse("application/pdf"),
          new File("document.pdf")
        )
      )
      .addFormDataPart(
        "instructions",
        new JSONObject()
          .put("parts", new JSONArray()
            .put(new JSONObject()
              .put("file", "document")
              .put("pages", new JSONObject()
                .put("start", 0)
                .put("end", 0)
              )
            )
            .put(new JSONObject()
              .put("file", "document")
            )
            .put(new JSONObject()
              .put("file", "document")
              .put("pages", new JSONObject()
                .put("start", -1)
                .put("end", -1)
              )
            )
          ).toString()
      )
      .build();

    final Request request = new Request.Builder()
      .url("https://api.nutrient.io/build")
      .method("POST", body)
      .addHeader("Authorization", "Bearer your_api_key_here")
      .build();

    final OkHttpClient client = new OkHttpClient()
      .newBuilder()
      .build();

    final Response response = client.newCall(request).execute();

    if (response.isSuccessful()) {
      Files.copy(
        response.body().byteStream(),
        FileSystems.getDefault().getPath("result.pdf"),
        StandardCopyOption.REPLACE_EXISTING
      );
    } else {
      // Handle the error
      throw new IOException(response.body().string());
    }
  }
}

using System;
using System.IO;
using System.Net;
using RestSharp;

namespace PspdfkitApiDemo
{
  class Program
  {
    static void Main(string[] args)
    {
      var client = new RestClient("https://api.nutrient.io/build");

      var request = new RestRequest(Method.POST)
        .AddHeader("Authorization", "Bearer your_api_key_here")
        .AddFile("document", "document.pdf")
        .AddParameter("instructions", new JsonObject
        {
          ["parts"] = new JsonArray
          {
            new JsonObject
            {
              ["file"] = "document",
              ["pages"] = new JsonObject
              {
                ["start"] = 0,
                ["end"] = 0
              }
            },
            new JsonObject
            {
              ["file"] = "document"
            },
            new JsonObject
            {
              ["file"] = "document",
              ["pages"] = new JsonObject
              {
                ["start"] = -1,
                ["end"] = -1
              }
            }
          }
        }.ToString());

      request.AdvancedResponseWriter = (responseStream, response) =>
      {
        if (response.StatusCode == HttpStatusCode.OK)
        {
          using (responseStream)
          {
            using var outputFileWriter = File.OpenWrite("result.pdf");
            responseStream.CopyTo(outputFileWriter);
          }
        }
        else
        {
          var responseStreamReader = new StreamReader(responseStream);
          Console.Write(responseStreamReader.ReadToEnd());
        }
      };

      client.Execute(request);
    }
  }
}

// This code requires Node.js. Do not run this code directly in a web browser.

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: {
        start: 0,
        end: 0
      }
    },
    {
      file: "document"
    },
    {
      file: "document",
      pages: {
        start: -1,
        end: -1
      }
    }
  ]
}))
formData.append('document', fs.createReadStream('document.pdf'))

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

    response.data.pipe(fs.createWriteStream("result.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")))
  })
}

import requests
import json

response = requests.request(
  'POST',
  'https://api.nutrient.io/build',
  headers = {
    'Authorization': 'Bearer your_api_key_here'
  },
  files = {
    'document': open('document.pdf', 'rb')
  },
  data = {
    'instructions': json.dumps({
      'parts': [
        {
          'file': 'document',
          'pages': {
            'start': 0,
            'end': 0
          }
        },
        {
          'file': 'document'
        },
        {
          'file': 'document',
          'pages': {
            'start': -1,
            'end': -1
          }
        }
      ]
    })
  },
  stream = True
)

if response.ok:
  with open('result.pdf', 'wb') as fd:
    for chunk in response.iter_content(chunk_size=8096):
      fd.write(chunk)
else:
  print(response.text)
  exit()

<?php

$FileHandle = fopen('result.pdf', 'w+');

$curl = curl_init();

curl_setopt_array($curl, array(
  CURLOPT_URL => 'https://api.nutrient.io/build',
  CURLOPT_CUSTOMREQUEST => 'POST',
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => '',
  CURLOPT_POSTFIELDS => array(
    'instructions' => '{
      "parts": [
        {
          "file": "document",
          "pages": {
            "start": 0,
            "end": 0
          }
        },
        {
          "file": "document"
        },
        {
          "file": "document",
          "pages": {
            "start": -1,
            "end": -1
          }
        }
      ]
    }',
    'document' => new CURLFILE('document.pdf')
  ),
  CURLOPT_HTTPHEADER => array(
    'Authorization: Bearer your_api_key_here'
  ),
  CURLOPT_FILE => $FileHandle,
));

$response = curl_exec($curl);

curl_close($curl);

fclose($FileHandle);

POST https://api.nutrient.io/build HTTP/1.1
Content-Type: multipart/form-data; boundary=--customboundary
Authorization: Bearer your_api_key_here

--customboundary
Content-Disposition: form-data; name="instructions"
Content-Type: application/json

{
  "parts": [
    {
      "file": "document",
      "pages": {
        "start": 0,
        "end": 0
      }
    },
    {
      "file": "document"
    },
    {
      "file": "document",
      "pages": {
        "start": -1,
        "end": -1
      }
    }
  ]
}
--customboundary
Content-Disposition: form-data; name="document"; filename="document.pdf"
Content-Type: application/pdf

(document data)
--customboundary--

Using Postman? Download our official collection and start using the API with a single click. Read more

Your API key

Security is our top priority

No document storage

No input or resulting documents are stored on our infrastructure. All files are deleted as soon as a request finishes. Alternatively, check out our self-hosted product.

HTTPS encryption

All communication between your application and Nutrient is done via HTTPS to ensure your data is encrypted when it’s sent to us.

Safe payment processing

All payments are handled by Paddle. Nutrient DWS Processor API never has direct access to any of your payment data.

Ready to try it?

Create an account to get your API key and start making API calls.

Start for free