Merge PDF API

Combine multiple PDF files into a single, organized document using a fast, secure, and reliable PDF merge API. Perfect for reports, archives, or batch processing.

Seamless document merging

Merge PDFs in any order with full control over page sequence. Ideal for assembling invoices, contracts, scanned forms, or multipart reports.

Automate with Zapier

Automatically merge new PDF files in Google Drive using our Zapier integration. Simply drop your PDFs into a folder, and let the Nutrient API handle the rest.

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.

Used by Lufthansa, Disney, Autodesk, UBS, Dropbox, IBM
Lufthansa
Disney
Autodesk
UBS
Dropbox
IBM

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.


Try it out in three steps

  1. Add two scanned PDFs named first-half.pdf and second-half.pdf to your project folder.
  2. Run the code from the same folder.
  3. Open result.pdf to see the output.
curl -X POST https://api.nutrient.io/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"
}
]
}'

Start now

Create an account to access your API key and start with 50 free credits per month

Start building with DWS Processor API in minutes — no payment information required.

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Security is our top priority

SOC 2 Type 2 audited

Nutrient’s infrastructure is SOC 2 Type 2 audited and GDPR-compliant. See our privacy policy and security documentation for details on data handling.

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.


PDF merge API questions

What is a PDF merge API?

A PDF merge API combines multiple PDF documents into a single output file over a REST endpoint. Nutrient’s DWS Processor API handles the merge through its build endpoint — each input PDF is added as a parts item, and the output is assembled in the same order.

How do I authenticate merge PDF API requests?

Each request is authenticated with an HTTP header of the form Authorization: Bearer your_api_key_here using either a live or a test API key. A JSON Web Token (JWT) generated from the API key can be used instead — JWTs can be scoped to specific operations and origins, time-limited, and revoked. See getting started for API key setup.

Can I reorder or duplicate pages while merging?

Yes. The order of the parts array controls the order of documents in the merged PDF, and the same input file can be referenced more than once with different page ranges to reorder or duplicate pages in the output — for example, placing the last page first.

Are there rate limits for the merge PDF API?

Yes. Live API keys are rate limited to 100 requests per minute per API key across all plan levels. Test API keys are limited to 10 requests per minute, with request and output size capped at 5 MB and watermarked output. See Processor API pricing for details.

Is the merge PDF API SOC 2-compliant?

Yes. The API is backed by Nutrient’s SOC 2 Type 2-audited infrastructure — built for use in business-critical and regulated workflows.

Is there a free tier for the merge PDF API?

Yes. Sign up to receive free processing credits and test PDF merging before choosing a plan. See the Processor API pricing page for credit details.

Ready to try it?

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