Anvil PDF Generation API vs iText Core

Anvil PDF Generation API creates PDFs on demand from HTML and CSS or Markdown. For HTML, it supports full CSS, custom TTF fonts, page dimensions and margins, headers and footers, page numbers, and fillable forms. Markdown conversion applies a default theme, and callers can provide CSS of their own. The API can also generate variable-length documents and merge data into PDFs. Anvil lists SDKs for C#/.NET, JavaScript, Python, and TypeScript; Go, Java, PHP, and Ruby are marked as coming soon. A Zapier integration can automate paperwork workflows, including filling a PDF or starting or pre-filling a Workflow. It is a cloud service with API and web access, email support, and listed SOC 2 and HIPAA compliance. Test mode is free and unlimited on every plan, though test documents are watermarked and use demo signatures. API PDF fill or generation costs $0.10 per use; enabling metered usage with a valid credit card provides 2,500 starter credits. The Free plan is free and UI-only; API key access requires a credit card or upgrade. Custom fonts must be TTF; OTF and WOFF are not supported.

iText Core has no write-up on Specifiction yet; its figures are above.