pdf-lib vs PyMuPDF
No leader: the top candidate pdf-lib has only 0.20 confidence (low), below the 0.35 needed to declare a winner. The attribute-by-attribute breakdown below, with a source and date on every value, is the honest way to compare them.
Capabilities
Feature-by-feature on the axes that matter for pdf editors. “-” means undocumented, not absent.
What each one is
The product in its own terms, so the numbers below have context.
pdf-lib
A pure JavaScript PDF manipulation toolkit that runs across any JavaScript environment including web browsers, Node.js, Deno, and React Native. It enables creating new PDFs, editing existing documents, filling forms with various field types, embedding fonts, and merging or splitting pages.
PyMuPDF
A Python library built on the MuPDF engine for reading, manipulating, converting, and annotating PDF and document files with integrated OCR support. Designed for local processing in air-gapped and regulated environments.
Pricing
List pricing as published by each vendor, with the date we read it. Always verify at the source before you buy.
Platform & deployment
Where each product runs and how it can be hosted. A dash means undocumented, not unsupported.
Comparison generated from independently-sourced facts. Every value links to its source and retrieval date. See the method.