/ Alternatives
The best HTML to PDF API in 2026 — honestly compared
An opinionated comparison of six HTML-to-PDF APIs worth evaluating in 2026 — DocRaptor, PDFShift, PDFCrowd, API2PDF, Prince, 21pdf — scored on what matters.
/ Blog
Writing for engineers
who ship documents.
In-depth posts on HTML-to-PDF APIs, Chromium rendering, CSS for print, SSRF hardening, async job models, and the rest of the document-infrastructure stack — grounded in the Go codebase that powers 21pdf.
/ Pillars
/ Chromium & headless browsers
How Chromium renders HTML into a PDF — architecture deep-dive
A working engineer's walk through the pipeline that turns HTML into a PDF inside headless Chromium — Blink, V8, print preview, CDP, Puppeteer.
/ CSS & print layout
CSS for print — @page, margins, page-breaks, the complete guide
Everything working engineers need to know about CSS for PDF output — @page rules, margins, page-breaks, headers, footers, page numbers, paged media.
/ HTML to PDF API
HTML to PDF API — the complete 2026 guide
Everything a working engineer needs to know about HTML-to-PDF APIs in 2026 — how they render, what to ask, and the pitfalls that actually bite in production.
/ Comparisons
HTML to PDF library vs API — when self-host wins, when it doesn't
A structured comparison of self-hosting Puppeteer/Playwright/Gotenberg vs using a managed HTML-to-PDF API — with the numbers that matter for the decision.
/ Invoices & documents
Generating invoice PDFs from an API — the complete playbook
A production playbook for generating invoice PDFs via an HTML-to-PDF API — template structure, US sales tax, EU VAT invoicing, edge cases, and delivery.
/ Production concerns
PDF rendering at scale — architecture for 1M PDFs/day
Operating an HTML-to-PDF service at production scale — queue design, Chromium pool sizing, rate limits, SSRF, monitoring, and the failure modes that actually bite.
/ Latest
/ Alternatives
The best HTML to PDF API in 2026 — honestly compared
An opinionated comparison of six HTML-to-PDF APIs worth evaluating in 2026 — DocRaptor, PDFShift, PDFCrowd, API2PDF, Prince, 21pdf — scored on what matters.
/ Chromium & headless browsers
How Chromium renders HTML into a PDF — architecture deep-dive
A working engineer's walk through the pipeline that turns HTML into a PDF inside headless Chromium — Blink, V8, print preview, CDP, Puppeteer.
/ CSS & print layout
CSS for print — @page, margins, page-breaks, the complete guide
Everything working engineers need to know about CSS for PDF output — @page rules, margins, page-breaks, headers, footers, page numbers, paged media.
/ Alternatives
DocRaptor alternatives — 5 options and when each wins in 2026
Fair comparison of DocRaptor alternatives — 21pdf, PDFShift, PDFCrowd, API2PDF, self-hosted Prince — with pricing, features, and the decision framework.
/ HTML to PDF API
HTML to PDF API — the complete 2026 guide
Everything a working engineer needs to know about HTML-to-PDF APIs in 2026 — how they render, what to ask, and the pitfalls that actually bite in production.
/ Language guides
HTML to PDF in Go — 3 options and the one most teams should pick
Convert HTML to PDF in Go with chromedp, rod, or a managed HTML-to-PDF API — full working code, comparison, and when to pick each.
/ Comparisons
HTML to PDF library vs API — when self-host wins, when it doesn't
A structured comparison of self-hosting Puppeteer/Playwright/Gotenberg vs using a managed HTML-to-PDF API — with the numbers that matter for the decision.
/ Language guides
HTML to PDF in Node.js — the practical 2026 guide
Four ways to turn HTML into a PDF from Node.js — Puppeteer, Playwright, html-pdf-node, and a managed API — with working code and when to pick each.
/ Language guides
HTML to PDF in Python — 4 options compared, with working code
Convert HTML to PDF in Python with Playwright, WeasyPrint, pdfkit (wkhtmltopdf), or a managed API — full working code and when to pick each.
/ Invoices & documents
Generating invoice PDFs from an API — the complete playbook
A production playbook for generating invoice PDFs via an HTML-to-PDF API — template structure, US sales tax, EU VAT invoicing, edge cases, and delivery.
/ Production concerns
PDF rendering at scale — architecture for 1M PDFs/day
Operating an HTML-to-PDF service at production scale — queue design, Chromium pool sizing, rate limits, SSRF, monitoring, and the failure modes that actually bite.
/ Alternatives
PDFShift alternatives — 5 options compared honestly in 2026
Fair comparison of PDFShift alternatives — 21pdf, PDFCrowd, DocRaptor, API2PDF, self-hosted — with pricing, feature gaps, and migration guidance.
/ Browse by category
HTML to PDF API
Using the 21pdf REST API — auth, request shape, response lifecycle, production patterns.
Language guides
Calling /v1/convert from Node, Python, Go, PHP, Ruby, Java, and raw curl.
Chromium & headless browsers
How Chromium renders PDFs — Puppeteer, Playwright, DevTools Protocol, wkhtmltopdf migration.
Alternatives
Fair comparisons with DocRaptor, PDFShift, API2PDF, PDFCrowd, Prince, and friends.
CSS & print layout
@page, margins, page-breaks, headers, footers, page numbers — how to get pixel-right PDFs.
Invoices & documents
Invoice, statement, receipt, and report generation — the bread-and-butter of PDF APIs.
Production concerns
SSRF, async job queues, webhooks vs polling, rate limits — what engineers worry about in a PDF renderer.
India SaaS & Razorpay
Building an Indian SaaS stack — Razorpay subscriptions, GST invoicing, INR pricing.
Comparisons
Library vs API, Puppeteer vs Playwright, self-hosted vs managed — head-to-head decisions.