PDF generation from HTML without managing servers

Your app generates invoices. Estimates. Contracts. Shipping labels. Every document becomes a PDF.

Currently: You run wkhtmltopdf on your server. It works... until it doesn't.

Wednesday 3 PM: wkhtmltopdf process hangs on a malformed HTML file. All PDF generation freezes. Customers can't download invoices. Support tickets pile up. By 5 PM, you're SSH'ing into production servers, killing processes manually.

There's a better way. A REST API that generates PDFs from HTML. No server to manage. No hanging processes. No complexity.

The self-hosted PDF generation trap

Most developers start with wkhtmltopdf or similar CLI tools:

const { execSync } = require('child_process');
const fs = require('fs');

function generatePDF(html, filename) {
  fs.writeFileSync('/tmp/input.html', html);

  execSync(`wkhtmltopdf /tmp/input.html /tmp/${filename}.pdf`, {
    timeout: 30000
  });

  const pdf = fs.readFileSync(`/tmp/${filename}.pdf`);
  fs.unlinkSync('/tmp/input.html');
  fs.unlinkSync(`/tmp/${filename}.pdf`);

  return pdf;
}

Looks simple. In production: nightmare.

Hidden costs

Process management

wkhtmltopdf hangs on malformed HTML → timeout → manual restart
No error recovery → customers stuck waiting
Requires /tmp cleanup (disk space issues)
System resource limits (ulimits) need tuning

Reliability

Font rendering differs by system setup
Timeouts are silent failures
Large files OOM the process
No graceful degradation

Scaling

Each PDF needs a new process spawn (~2 seconds)
Can't run 100 PDFs/second without horizontal scaling
Vertical scaling hits ceiling

Real cost: $50–100/month infrastructure + 3–5 hours DevOps = ~$700/month effective cost.

Solution: Hosted PDF API

Call an endpoint. Get a PDF back. That's it.

curl -X POST https://pagebolt.dev/api/v1/pdf \
  -H "x-api-key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "html": "<h1>Invoice #12345</h1><p>Total: $99.99</p>",
    "format": "A4",
    "margin": "1in"
  }' \
  --output invoice.pdf

No infrastructure. No process management. No timeouts.

Before and after

Self-hosted approach

const express = require('express');
const { execSync } = require('child_process');
const fs = require('fs');
const path = require('path');

app.post('/invoice/:invoiceId', (req, res) => {
  try {
    const html = req.body.html;
    const filename = `invoice-${req.params.invoiceId}`;
    const tmpInput = path.join('/tmp', `${filename}.html`);
    const tmpOutput = path.join('/tmp', `${filename}.pdf`);

    fs.writeFileSync(tmpInput, html);

    // This can hang, timeout, or fail silently
    execSync(`wkhtmltopdf --margin-top 10 --margin-bottom 10 ${tmpInput} ${tmpOutput}`, {
      timeout: 30000,
      stdio: 'pipe'
    });

    const pdf = fs.readFileSync(tmpOutput);
    fs.unlinkSync(tmpInput);
    fs.unlinkSync(tmpOutput);

    res.set('Content-Type', 'application/pdf');
    res.set('Content-Disposition', `attachment; filename="${filename}.pdf"`);
    res.send(pdf);
  } catch (error) {
    console.error('PDF generation failed:', error);
    res.status(500).send('PDF generation failed');
  }
});

Cost: $50–100/month infrastructure + 3–5 hours DevOps = ~$700/month effective.

Hosted API approach

app.post('/invoice/:invoiceId', async (req, res) => {
  try {
    const response = await fetch('https://pagebolt.dev/api/v1/pdf', {
      method: 'POST',
      headers: {
        'x-api-key': process.env.PAGEBOLT_API_KEY,
        'Content-Type': 'application/json'
      },
      body: JSON.stringify({
        html: req.body.html,
        format: 'A4',
        margin: '1in'
      })
    });

    const pdf = Buffer.from(await response.arrayBuffer());

    res.set('Content-Type', 'application/pdf');
    res.set('Content-Disposition', `attachment; filename="invoice-${req.params.invoiceId}.pdf"`);
    res.send(pdf);
  } catch (error) {
    res.status(500).send('PDF generation failed');
  }
});

Cost: $29/month (Starter, 5,000 PDFs/month), $0 infrastructure, $0 DevOps = $29/month total.

Real example: Invoice generation + email

E-commerce platform: generate invoice PDF, email to customer, archive to S3.

const nodemailer = require('nodemailer');
const AWS = require('aws-sdk');

async function generateAndEmailInvoice(order) {
  const html = `
    <h1>Invoice</h1>
    <p>Order ID: ${order.id}</p>
    <table>
      ${order.items.map(item => `
        <tr>
          <td>${item.name}</td>
          <td>$${item.price}</td>
        </tr>
      `).join('')}
    </table>
    <p>Total: $${order.total}</p>
  `;

  // Generate PDF
  const res = await fetch('https://pagebolt.dev/api/v1/pdf', {
    method: 'POST',
    headers: {
      'x-api-key': process.env.PAGEBOLT_API_KEY,
      'Content-Type': 'application/json'
    },
    body: JSON.stringify({ html, format: 'A4' })
  });
  const pdf = Buffer.from(await res.arrayBuffer());

  // Email to customer
  await nodemailer.createTransport({/* ... */}).sendMail({
    from: 'noreply@mystore.com',
    to: order.customer.email,
    subject: `Invoice for Order #${order.id}`,
    text: 'Your invoice is attached.',
    attachments: [{ filename: `invoice-${order.id}.pdf`, content: pdf }]
  });

  // Archive to S3
  await new AWS.S3().putObject({
    Bucket: 'invoices-archive',
    Key: `${order.id}.pdf`,
    Body: pdf
  }).promise();

  return { success: true, invoiceId: order.id };
}

Simple, reliable, no process management.

Comparison: wkhtmltopdf vs hosted API

Factor	wkhtmltopdf	Hosted API
Setup	1–2 hours	10 minutes
Infra cost	$50–100/month	$0
DevOps time	3–5 hours/month	0 hours
Latency	2–5 seconds	1–2 seconds
Reliability	99% (hangs, timeouts)	99.9% SLA
Scaling	Capped at server	Unlimited
Font support	System-dependent	Consistent
Custom styling	Limited	Full CSS3
Per-PDF cost	$0.05–0.10 (infra)	$0.02–0.05 (API)

When to use hosted PDF API

✅ User-facing invoice/receipt generation
✅ Automated document pipelines
✅ Report generation at scale
✅ Limited DevOps resources
✅ Unpredictable volume

Keep wkhtmltopdf if:

You process 10,000+ PDFs/day (break-even at scale)
You have dedicated DevOps
Documents require extreme customization not achievable via HTML/CSS

For most teams: hosted wins.

Getting started

Sign up at pagebolt.dev (free: 100 requests/month)
Get API key from your dashboard (1 minute)
Make your first PDF (5 minutes)
Evaluate: Does it solve your use case?

No more hanging processes. No more 3 AM PDF generation failures.