Merge PDF API

Merge multiple files into one document with our PDF merging API.

Try It Out

This example will merge the two supplied documents into one PDF. The order of the documents in the final PDF is controlled by the order of the parts array.

1

Use Your Free Credits

Sign up to get 100 free credits, or log in to automatically add your API key to sample code.

Add a File

Add two PDFs named first_half.pdf and second_half.pdf to your project folder. You can also use our sample files: first_half.pdf and second_half.pdf. 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.

curl -X POST https://api.pspdfkit.com/build \
  -H "Authorization: Bearer your_api_key_here" \
  -o result.pdf \
  --fail \
  -F first_half=@first_half.pdf \
  -F second_half=@second_half.pdf \
  -F instructions='{
      "parts": [
        {
          "file": "first_half"
        },
        {
          "file": "second_half"
        }
      ]
    }'
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(
        "first_half",
        "first_half.pdf",
        RequestBody.create(
          new File("first_half.pdf"),
          MediaType.parse("application/pdf")
        )
      )
      .addFormDataPart(
        "second_half",
        "second_half.pdf",
        RequestBody.create(
          new File("second_half.pdf"),
          MediaType.parse("application/pdf")
        )
      )
      .addFormDataPart(
        "instructions",
        new JSONObject()
          .put("parts", new JSONArray()
            .put(new JSONObject()
              .put("file", "first_half")
            )
            .put(new JSONObject()
              .put("file", "second_half")
            )
          ).toString()
      )
      .build();

    final Request request = new Request.Builder()
      .url("https://api.pspdfkit.com/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.pspdfkit.com/build");

      var request = new RestRequest(Method.POST)
        .AddHeader("Authorization", "Bearer your_api_key_here")
        .AddFile("first_half", "first_half.pdf")
        .AddFile("second_half", "second_half.pdf")
        .AddParameter("instructions", new JsonObject
        {
          ["parts"] = new JsonArray
          {
            new JsonObject
            {
              ["file"] = "first_half"
            },
            new JsonObject
            {
              ["file"] = "second_half"
            }
          }
        }.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);
    }
  }
}
const axios = require('axios')
const FormData = require('form-data')
const fs = require('fs')

const formData = new FormData()
formData.append('instructions', JSON.stringify({
  parts: [
    {
      file: "first_half"
    },
    {
      file: "second_half"
    }
  ]
}))
formData.append('first_half', fs.createReadStream('first_half.pdf'))
formData.append('second_half', fs.createReadStream('second_half.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("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

instructions = {
  'parts': [
    {
      'file': 'first_half'
    },
    {
      'file': 'second_half'
    }
  ]
}

response = requests.request(
  'POST',
  'https://api.pspdfkit.com/build',
  headers = {
    'Authorization': 'Bearer your_api_key_here'
  },
  files = {
    'first_half': open('first_half.pdf', 'rb'),
    'second_half': open('second_half.pdf', 'rb')
  },
  data = {
    'instructions': json.dumps(instructions)
  },
  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();

$instructions = '{
  "parts": [
    {
      "file": "first_half"
    },
    {
      "file": "second_half"
    }
  ]
}';

curl_setopt_array($curl, array(
  CURLOPT_URL => 'https://api.pspdfkit.com/build',
  CURLOPT_CUSTOMREQUEST => 'POST',
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => '',
  CURLOPT_POSTFIELDS => array(
    'instructions' => $instructions,
    'first_half' => new CURLFILE('first_half.pdf'),
    'second_half' => new CURLFILE('second_half.pdf')
  ),
  CURLOPT_HTTPHEADER => array(
    'Authorization: Bearer your_api_key_here'
  ),
  CURLOPT_FILE => $FileHandle,
));

$response = curl_exec($curl);

curl_close($curl);

fclose($FileHandle);

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