The PDF API that saves you time, money, and headaches

Generate up to 600 free documents every month with our PDF API. Convert HTML to PDF, PDF to PNG, or merge PDF workflows with ease using simple JavaScript. CustomJS is more affordable than most other PDF APIs and works seamlessly anywhere, including Make.com and n8n.

✅ 600 Free Documents Every Month

💸 Cheaper Than Other PDF APIs

🛠️ No New Servers Needed

Start free with 600 PDFs per month

Or use our standalone PDF API anywhere

A PDF API allows you to create, edit, merge, and convert PDF files automatically—no manual steps required. But most APIs are slow, costly, or overly complex. CustomJS changes that with fast, serverless PDF generation powered by simple JavaScript. Convert HTML to PDF efficiently—saving both time and money.

Lower Cost: Save money every month with simple, honest pricing.
Faster Speed: Get your output PDF files instantly without waiting.
More Flexibility: Build exactly what you want with serverless JavaScript anywhere.

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Use other examples to quickly create and work with PDFs

Quickly create, merge, compress, and convert files with our ready-to-use PDF API endpoints. Build your own PDF generation API that fits your needs.

PDF to PNG – Turn PDF pages into png images. View preset
PDF to Text – Extract texts from PDF. View preset
Merge PDFs – Combine invoices, reports, attachments. View preset
Extract Pages from PDF – Pull selected pages into new PDF. View preset
Compress a PDF – Shrink file size by 70% easily. View preset
Take a Website Screenshot – Capture websites into clear PNGs. View preset

Build your own custom API with our pdfUtils

Customize your PDF generation API Using JavaScript

Need full control over your PDF generator API? Our pdfUtils allows you to create customizable documents for HTML-to-PDF conversions, compress PDF files, merge PDF JavaScript, or extract pages. No servers. No advanced tools. Just your code, your rules.

const { PDF_MERGE, HTML2PDF } = require('./utils');

let pages = [
    input.page1,
    input.page2,
    input.page3,
    input.page4,
    input.page5,
    input.page6,
    input.page7,
    input.page8,
    input.page9,
    input.page10,
    input.page11
];

pages = await Promise.all(pages.filter(i => i).map(i => HTML2PDF(i)));

return PDF_MERGE(pages);

This example shows how you can pass an array of HTML pages, generate a PDF for each one, and then merge them into a single file.

curl -X POST https://e.customjs.io/zeXXXy \
  -H "Content-Type: application/json" \
  -H "x-api-key: YOUR_API_KEY_HERE" \
  -d '{
    "page1": "<html>...</html>",
    "page2": "<html>...</html>",
    "page3": "<html>...</html>",
    "page4": "<html>...</html>",
    "page5": "<html>...</html>",
    "page6": "<html>...</html>",
    "page7": "<html>...</html>",
    "page8": "<html>...</html>",
    "page9": "<html>...</html>",
    "page10": "<html>...</html>",
    "page11": "<html>...</html>"
  }' > test.pdf

This is how you would call your custom api.

Affordable HTML-to-PDF Conversion

CustomJS gives you 600 PDF/API calls every month for free, then scales from just $9 for 3,000+ calls, beating the “PDF-as-a-Service” incumbents on both cost and flexibility.

Feature	CustomJS	ConvertAPI	DocRaptor	Api2PDF
Free Tier	600 req/mo, no credit card	250 trial conv.	None	None
Starter Plan	$9/mo	$30/mo	$15/mo	$1 base + usage
Billing Type	Per document (no setup)	Per conv.	Quota + usage	Time + file size
Integrations	Make.com, n8n, Zapier	REST API	PrinceXML	wkhtmltopdf, ChromeHead

FAQs

What is a PDF API, and how does CustomJS help?
A PDF API lets you create, edit, and manage PDF files automatically with simple API calls. CustomJS offers a powerful API and an affordable option to build HTML-to-PDF workflows, merge PDF files, compress documents, and support a wide range of PDF actions, without expensive setup or server costs.

Can I use CustomJS to convert HTML to PDF?
Yes. Our HTML to PDF API makes it easy to convert dynamic HTML or CSS into pixel-perfect PDFs. You can build PDF creation flows within Make.com or n8n using our dynamic PDF generator.

How much does it cost to use CustomJS’s PDF API?
You can generate up to 600 PDF documents per month for free. After that, our starter plan is only $9 per month.

Can I merge multiple PDF files using CustomJS?
Yes, you can use our merge PDF API to combine invoices, reports, or multiple PDF documents into a single file quickly.

Does CustomJS allow me to compress PDF files?
Absolutely. Our compress PDF JS functionality lets you shrink PDF file size by up to 70% without losing quality.

Can I extract pages from a PDF with JavaScript using CustomJS? Yes, you can use JavaScript to extract pages and create new files without extra tools.

Can I convert PDFs to images using CustomJS?
Yes. With CustomJS, you can easily convert PDF to PNG in your workflows.

Is CustomJS easy to integrate with Make.com and n8n?
Yes, you don't need any new server setup—just call our REST API.

The PDF API that saves you time, money, and headaches

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