The honest summary
DocRaptor is a wrapper around Prince XML, the commercial print-quality HTML-to-PDF engine. Prince produces beautiful output, especially for typographically heavy documents (books, journals, complex tables). It has been around since 2003 and powers a lot of the PDFs you read.
LightningPDF runs two engines: a Go-native fast path for simple documents and a Chromium engine for complex layouts. Chromium is what your browser uses, which is why webfonts, complex scripts, and modern CSS work without ceremony.
If you are choosing between us purely on the strength of the print typography (multi-column layouts, hyphenation across languages, footnote handling), Prince wins. If you are choosing on multilingual support, structured e-invoice output, or sub-100ms latency for simple documents, we win.
Feature matrix
| Capability | LightningPDF | DocRaptor |
|---|---|---|
| HTML to PDF | yes | yes |
| Webfonts (Google Fonts, @font-face) | yes | yes |
| Indic scripts (Hindi, Bengali, Tamil) | yes, no config | requires manual font setup |
| Arabic / Hebrew (RTL) | yes, no config | yes with font config |
| CJK | yes, no config | yes with font config |
| Chromium engine | yes, the default | no |
| Prince XML engine | no | yes, the default |
| Go-native sub-100ms path | yes, for simple HTML | no |
| Validator-passing Peppol BIS 3.0 | yes (Pro) | no |
| Validator-passing ZUGFeRD / Factur-X | yes (Pro) | no |
| ZATCA Phase 2 | yes (Pro) | no |
| Merge / split / compress | yes | no |
| Free tier | 100/mo, no card | 7-day trial, then card |
| WordPress plugin | yes (Paperbolt) | no |
| Shopify app | yes (Paperbolt) | no |
Pricing at the entry tier
Per 1,000 PDFs at the smallest plan:
| Plan | LightningPDF | DocRaptor |
|---|---|---|
| Free | $0 (100 PDFs/mo) | 7-day trial |
| Lowest paid | $9/mo for 500 ($0.018 each) | $15/mo for 125 ($0.12 each) |
| Lowest paid per 1k | $18 | $120 |
DocRaptor's per-PDF cost narrows substantially at the Pro and Enterprise tiers. If you generate over 100,000 PDFs per month, walk through both pricing pages with your actual mix to compare.
When DocRaptor is the right choice
- You need Prince XML's typography. Multi-language hyphenation, advanced footnote layout, and journal-quality output beat what either Chromium or wkhtmltopdf can produce.
- You already use the Ruby or Python client and the workflow is stable.
- You have an existing contract and the migration cost is higher than the multilingual gap.
When LightningPDF is the right choice
- Your audience reads Hindi, Bengali, Tamil, Arabic, Hebrew, Thai, or CJK. Our renderer is Chromium, which handles complex scripts identically to how Chrome does. DocRaptor can do this with font configuration; we do it with zero configuration.
- You face the Belgian B2B mandate (2026-01-01), the German ZUGFeRD mandate (2027-01-01 over EUR 800k, 2028-01-01 all), Saudi ZATCA Phase 2, India GST, or Japan qualified invoice. We emit the structured XML; DocRaptor does not.
- You want a free tier to prototype against before paying. 100 PDFs/mo, no card.
- You need merge, split, compress, or text extraction in the same API. DocRaptor focuses on generation only.
What we will not claim
We will not claim Prince XML output is reproducible in Chromium. It is not. If your output today depends on Prince-specific features (-prince-no-author-style, -prince-table-rendering: realistic, footnote area layout) the migration will be painful. Be honest with yourself about whether you actually use those features or just inherited them.