DocSpring vs wkhtmltopdf

Why wkhtmltopdf is still around

wkhtmltopdf is a command-line tool that converts HTML to PDF using QtWebKit. Its builds link Qt statically, which made it easy to drop into Rails, Django, PHP, and .NET projects through wrapper libraries such as wicked_pdf, pdfkit, and snappy. Many of those integrations are still running.

wkhtmltopdf is no longer maintained. Its GitHub repository was archived in January 2023, the last release was 0.12.6 in June 2020, and the QtWebKit engine it depends on was removed from Qt in 2016. Layouts that rely on flexbox, CSS grid, modern fonts, or newer JavaScript often render incorrectly, and teams end up maintaining a second, simplified stylesheet just for PDF output.

Feature comparison

Follow the feature links for details in DocSpring's documentation. Sources for each wkhtmltopdf cell are listed at the end of the page.

Scroll the table sideways to see both products.

"Limited or your responsibility" marks things the library only partly covers or leaves to your own code and infrastructure. Plan requirements and product boundaries are noted in the cells.

One invoice, one stylesheet

The same customer and line items rendered from HTML. The difference is which browser engine renders it and whether you can use the CSS you write for the web.

Convert the invoice with wkhtmltopdf

The command itself is simple. The work is in the HTML that has to render correctly in a 2012 browser engine.

# Render the HTML with your own template engine first, then convert it.
wkhtmltopdf \
  --page-size A4 \
  --enable-local-file-access \
  --disable-smart-shrinking \
  invoice.html invoice.pdf

Generate the invoice with DocSpring

The same invoice as a Liquid template stored in DocSpring, rendered with current Chromium.

<h1>Invoice for {{ customer_name | escape }}</h1>
<table>
  <tr><th>Description</th><th>Amount (USD)</th></tr>
  {% for item in items %}
    <tr>
      <td>{{ item.description | escape }}</td>
      <td>{{ item.amount | currency }}</td>
    </tr>
  {% endfor %}
</table>

curl --fail-with-body \
  "https://sync.api.docspring.com/api/v1/templates/${DOCSPRING_TEMPLATE_ID}/submissions" \
  --user "${DOCSPRING_TEST_TOKEN_ID}:${DOCSPRING_TEST_TOKEN_SECRET}" \
  --header 'Content-Type: application/json' \
  --data '{
    "test": true,
    "data": {
      "customer_name": "Mira Patel",
      "items": [
        { "description": "Annual inspection", "amount": 120 },
        { "description": "Replacement filter", "amount": 35 }
      ]
    }
  }'

Set the environment variables to your template ID and test API credentials. Accounts in our EU region send requests to sync.api-eu.docspring.com instead. The response includes a download URL for a watermarked PDF. See the request and response guide.

Render your existing invoice in a current browser and compare it with the wkhtmltopdf output. The differences you find are the workarounds you have been maintaining.

Free, with a maintenance bill that has already come due

Count the hours your team has spent on "why does this look different in the PDF" in the last year. That is the price you are paying for a free tool, before any security review.

Moving from wkhtmltopdf to DocSpring

Take the HTML your wrapper library produces and paste it into a DocSpring HTML template. Remove the wkhtmltopdf-specific CSS workarounds, because DocSpring renders with headless Chromium and supports modern CSS. Replace your template engine's loops with Liquid.

Replace the shell-out with an API call from your existing language. DocSpring has official client libraries, or use plain HTTP. Delete the binary from your container image.

If you also stamp values onto existing PDFs with another tool, upload those PDFs to DocSpring and place the fields visually.

Discuss your documents with us.

Questions about wkhtmltopdf and DocSpring

Is wkhtmltopdf still maintained?

No. wkhtmltopdf is no longer maintained. Its GitHub repository was archived in January 2023, and the last release was version 0.12.6 in June 2020. Wrapper libraries such as wicked_pdf and pdfkit still work but cannot fix problems in the underlying engine.

Will my wkhtmltopdf HTML work in DocSpring?

Yes, and usually better. DocSpring renders with headless Chromium, so CSS that needed workarounds in QtWebKit generally renders as it does in your browser. Review page-break rules and any wkhtmltopdf-specific header and footer options.

Can wkhtmltopdf fill PDF forms?

No. It only converts HTML to a new PDF. DocSpring fills existing PDFs and lets you place the fields visually.