PDF merge split API

If you’re looking for a PDF merge/split API, here are the common options depending on what you need:

1) Hosted cloud APIs

Good if you want simple HTTP calls and don’t want to manage PDF libraries yourself.

• Adobe PDF Services API
  • Merge, split, compress, convert, OCR, etc.
  • Good enterprise support
• PSPDFKit / Nutrient API
  • Strong PDF processing and document workflows
• PDF.co API
  • Easy REST API for merge/split and many PDF tasks
• iLovePDF API
  • Merge, split, convert, and more
• Smallpdf API
  • Similar document processing capabilities

2) Self-hosted / library-based

Good if you want to run it in your own backend.

• PyPDF2 / pypdf (Python)
• PDFBox (Java)
• qpdf (CLI/library)
• iText (Java/.NET, commercial licensing may apply)
• Ghostscript (for some PDF operations)

Example API design

If you’re building your own API, common endpoints are:

• POST /pdf/merge
• POST /pdf/split
• POST /pdf/compress
• POST /pdf/convert

Merge request example

{
  "files": [
    "https://example.com/a.pdf",
    "https://example.com/b.pdf"
  ]
}

Split request example

{
  "file": "https://example.com/input.pdf",
  "ranges": ["1-3", "4-6"]
}

Simple Python example with pypdf

from pypdf import PdfMerger, PdfReader, PdfWriter

# Merge
merger = PdfMerger()
merger.append("a.pdf")
merger.append("b.pdf")
merger.write("merged.pdf")
merger.close()

# Split
reader = PdfReader("input.pdf")
writer = PdfWriter()
writer.add_page(reader.pages[0])
with open("page1.pdf", "wb") as f:
    writer.write(f)

If you want, I can also give you:

1. a ready-to-use REST API spec,
2. a Node.js/Python implementation, or
3. a comparison table of the best PDF APIs.