Do I still need Wicked PDF or wkhtmltopdf in Rails?

No. PDFgen renders for you, so a single Net::HTTP call replaces the Wicked PDF + wkhtmltopdf stack.

How do I send the PDF to the user?

Use send_data with type: "application/pdf" and a filename, as shown — Rails streams it as a download.

Can I use a gem like Faraday or HTTParty instead?

Yes — any HTTP client works. The example uses Net::HTTP only to avoid adding a dependency.

Ruby

Generate PDFs in Ruby on Rails

Generate and send a PDF from a Rails controller with the standard library — no Wicked PDF.

PDF generation in Rails usually pulls in Wicked PDF or Prawn plus a wkhtmltopdf binary. PDFgen needs neither: POST your HTML and data with Net::HTTP from the standard library and send_data the result.

The controller action below renders a downloadable invoice. Swap in any HTML — including an ERB partial rendered to a string.

Generate a PDF in Ruby on Rails

POST your HTML and data to /api/v1/generate with your API key, then save the PDF that comes back. Swap in your own HTML or a saved template_id and loop over records to render at scale.

require "net/http"
require "json"

# app/controllers/invoices_controller.rb
class InvoicesController < ApplicationController
  def show
    res = Net::HTTP.post(
      URI("https://pdfgen.com/api/v1/generate"),
      {
        html: "<h1>Invoice {{number}}</h1><p>Billed to {{client}} — total {{total}}</p>",
        engine: "handlebars",
        format: "A4",
        data: { number: "INV-001", client: "Acme Corp", total: "$2,400.00" }
      }.to_json,
      "Authorization" => "Bearer #{Rails.application.credentials.pdfgen_key}",
      "Content-Type" => "application/json"
    )

    send_data res.body, filename: "invoice.pdf", type: "application/pdf"
  end
end

Convert existing HTML to PDF in Ruby on Rails

Already have finished HTML? Skip templating — render an ERB view to HTML, then convert it and send it with engine: "legacy", which tells the API your markup is final.

require "net/http"
require "json"

class InvoicesController < ApplicationController
  def show
    # Render an existing ERB view to an HTML string.
    html = render_to_string(template: "invoices/show", layout: false)

    res = Net::HTTP.post(
      URI("https://pdfgen.com/api/v1/generate"),
      { html: html, engine: "legacy", format: "A4" }.to_json,
      "Authorization" => "Bearer #{Rails.application.credentials.pdfgen_key}",
      "Content-Type" => "application/json"
    )

    send_data res.body, filename: "invoice.pdf", type: "application/pdf"
  end
end

How it works

1
Send your HTML + data
POST an HTML template (with optional Handlebars tokens) and a data object to the API.
2
We render the PDF
PDFgen renders it server-side — no headless browser for you to run or scale.
3
Get the PDF back
Receive the PDF binary (or a hosted link with export_type:"url") and serve it from Ruby on Rails.

Good to know

Net::HTTP ships with Ruby — no extra gem to add.
Store the key in Rails credentials or an environment variable, not in source.
Render an ERB template to a string and pass it as the html field if you prefer building markup in Rails.

Frequently asked questions

Do I still need Wicked PDF or wkhtmltopdf in Rails?: No. PDFgen renders for you, so a single Net::HTTP call replaces the Wicked PDF + wkhtmltopdf stack.
How do I send the PDF to the user?: Use send_data with type: "application/pdf" and a filename, as shown — Rails streams it as a download.
Can I use a gem like Faraday or HTTParty instead?: Yes — any HTTP client works. The example uses Net::HTTP only to avoid adding a dependency.

Generate PDFs in other languages

Node.js Next.js React Python Django Laravel PHP Go

Your first PDF from Ruby on Rails in five minutes

Grab an API key, paste the snippet above, and render a PDF — no headless browsers to babysit. Build a reusable template with AI when you're ready.