pdf-oxide-wasm

Fast, zero-dependency PDF toolkit for Node.js, browsers, and serverless edge runtimes. Extract text, convert to markdown/HTML, search, fill forms, create and edit PDFs — all from WebAssembly.

Built on the pdf-oxide Rust core. No native binaries, no system dependencies.

Why pdf-oxide-wasm

| Feature | pdf-oxide-wasm | pdf-parse | pdf-lib | pdfjs-dist | |---|---|---|---|---| | Text extraction | Yes | Yes | No | Yes | | Markdown / HTML output | Yes | No | No | No | | PDF creation | Yes | No | Yes | No | | Form field read/write | Yes | No | Partial | No | | Full-text search (regex) | Yes | No | No | No | | Image extraction | Yes | No | No | No | | Merge, encrypt, edit | Yes | No | Yes | No | | Serverless / edge runtimes | Yes | No | No | No | | Zero native dependencies | Yes | Yes | Yes | No | | WebAssembly-based | Yes | No | No | No | | TypeScript types included | Yes | No | Yes | Yes | | License | MIT / Apache-2.0 | MIT | MIT | Apache-2.0 |

Install

npm install pdf-oxide-wasm

Quick Start

Extract text (Node.js — CommonJS)

const { WasmPdfDocument } = require("pdf-oxide-wasm");
const fs = require("fs");

const bytes = new Uint8Array(fs.readFileSync("document.pdf"));
const doc = new WasmPdfDocument(bytes);

console.log(`Pages: ${doc.pageCount()}`);
console.log(doc.extractText(0));       // plain text from page 0
console.log(doc.toMarkdown(0));        // markdown from page 0
console.log(doc.toHtml(0));            // HTML from page 0

doc.free();

Extract text (ESM / TypeScript)

import { WasmPdfDocument } from "pdf-oxide-wasm";
import { readFile } from "fs/promises";

const bytes = new Uint8Array(await readFile("document.pdf"));
const doc = new WasmPdfDocument(bytes);

const text = doc.extractAllText();
const markdown = doc.toMarkdownAll();

doc.free();

Create a PDF from Markdown

import { WasmPdf } from "pdf-oxide-wasm";

const pdf = WasmPdf.fromMarkdown("# Invoice\n\nTotal: $42.00", "Invoice", "Acme Corp");
const bytes = pdf.toBytes(); // Uint8Array — write to file or send as response

Search inside a PDF

const results = doc.search("quarterly revenue", true); // case-insensitive
// Returns: [{ page, text, bbox, start_index, end_index, span_boxes }]

Read and fill form fields

const fields = doc.getFormFields();
// [{ name, field_type, value, tooltip, bounds, is_readonly, is_required }]

doc.setFormFieldValue("name", "Jane Doe");
doc.setFormFieldValue("agree_terms", true);

const filledPdf = doc.saveToBytes(); // Uint8Array

Encrypt a PDF (AES-256)

const encrypted = doc.saveEncryptedToBytes(
  "user-password",
  "owner-password",
  true,  // allow print
  false, // deny copy
);

Features

Text Extraction — plain text, Markdown, and HTML output formats. Character-level and span-level extraction with bounding boxes, font names, sizes, weights, colors, and italic flags.

Format Conversion — convert any page or all pages to Markdown (with heading detection, images, form fields), HTML (with optional CSS layout preservation), or structured plain text.

Full-Text Search — regex and literal search across all pages or a single page. Case-insensitive, whole-word, and max-results options. Returns match positions with bounding boxes.

Image Extraction — extract image metadata (dimensions, color space, bits per component, bounding boxes) and raw image bytes as PNG.

Form Fields — read all AcroForm fields (text, button, choice, signature). Get/set individual field values. Export form data as FDF or XFDF. Flatten forms into static content. XFA detection.

PDF Creation — generate PDFs from Markdown, HTML, plain text, or images (PNG/JPEG). Multi-image support (one page per image). Set title, author metadata.

PDF Editing — set document metadata (title, author, subject, keywords). Rotate pages, set MediaBox/CropBox, crop margins. Erase (whiteout) regions. Reposition, resize, and set bounds on images. Flatten or apply redactions. Merge PDFs. Embed files.

Encryption — AES-256 encryption with granular permissions (print, copy, modify, annotate).

Document Structure — bookmarks/outline (table of contents), annotations (links, comments, form widgets), page labels, XMP metadata, vector paths.

API Reference

WasmPdfDocument — read, extract, search, and edit existing PDFs

| Method | Description | |---|---| | new(data) | Load PDF from Uint8Array | | pageCount() | Number of pages | | version() | PDF version as [major, minor] | | authenticate(password) | Decrypt an encrypted PDF | | hasStructureTree() | Check for Tagged PDF structure | | Text Extraction | | | extractText(page) | Plain text from one page | | extractAllText() | Plain text from all pages | | extractChars(page) | Character-level data with positions | | extractSpans(page) | Span-level data with positions | | Format Conversion | | | toMarkdown(page, headings?, images?, forms?) | Markdown from one page | | toMarkdownAll(headings?, images?, forms?) | Markdown from all pages | | toHtml(page, layout?, headings?, forms?) | HTML from one page | | toHtmlAll(layout?, headings?, forms?) | HTML from all pages | | toPlainText(page) | Plain text with layout | | toPlainTextAll() | Plain text all pages | | Search | | | search(pattern, caseInsensitive?, literal?, wholeWord?, max?) | Search all pages | | searchPage(page, pattern, ...) | Search one page | | Images | | | extractImages(page) | Image metadata (dimensions, color space, bbox) | | extractImageBytes(page) | Image data as PNG Uint8Array | | pageImages(page) | Image placement info (bounds, matrix) | | Forms | | | getFormFields() | All form fields with types and values | | getFormFieldValue(name) | Get a single field value | | setFormFieldValue(name, value) | Set a field value | | exportFormData(format?) | Export as FDF or XFDF | | hasXfa() | Check for XFA form data | | flattenForms() | Flatten all form fields | | flattenFormsOnPage(page) | Flatten fields on one page | | Document Structure | | | getOutline() | Bookmarks / table of contents | | getAnnotations(page) | Page annotations | | extractPaths(page) | Vector paths (lines, curves) | | pageLabels() | Page label ranges | | xmpMetadata() | XMP metadata | | Editing | | | setTitle(title) | Set document title | | setAuthor(author) | Set document author | | setSubject(subject) | Set document subject | | setKeywords(keywords) | Set document keywords | | setPageRotation(page, degrees) | Set page rotation | | rotatePage(page, degrees) | Rotate page by degrees | | rotateAllPages(degrees) | Rotate all pages | | pageMediaBox(page) | Get MediaBox | | setPageMediaBox(page, llx, lly, urx, ury) | Set MediaBox | | pageCropBox(page) | Get CropBox | | setPageCropBox(page, llx, lly, urx, ury) | Set CropBox | | cropMargins(left, right, top, bottom) | Crop all page margins | | eraseRegion(page, llx, lly, urx, ury) | Whiteout a region | | eraseRegions(page, rects) | Whiteout multiple regions | | repositionImage(page, name, x, y) | Move an image | | resizeImage(page, name, w, h) | Resize an image | | setImageBounds(page, name, x, y, w, h) | Set image bounds | | flattenPageAnnotations(page) | Flatten page annotations | | flattenAllAnnotations() | Flatten all annotations | | applyPageRedactions(page) | Apply redactions on page | | applyAllRedactions() | Apply all redactions | | mergeFrom(data) | Merge another PDF | | embedFile(name, data) | Embed a file | | Save | | | saveToBytes() | Save edits → Uint8Array | | saveEncryptedToBytes(userPwd, ownerPwd?, ...) | Save with AES-256 encryption | | free() | Release WASM memory |

WasmPdf — create new PDFs

| Method | Description | |---|---| | fromMarkdown(content, title?, author?) | Create PDF from Markdown | | fromHtml(content, title?, author?) | Create PDF from HTML | | fromText(content, title?, author?) | Create PDF from plain text | | fromImageBytes(data) | Create PDF from image (PNG/JPEG) | | fromMultipleImageBytes(images) | Create multi-page PDF from images | | toBytes() | Get PDF as Uint8Array | | size | PDF size in bytes |

Platform Compatibility

Works without modification in:

• Node.js 18+ (CommonJS and ESM)
• Browsers — Chrome, Firefox, Safari, Edge
• Cloudflare Workers — runs in V8 isolates with WASM support
• Deno — native WASM support
• Bun — native WASM support

No native binaries, no node-gyp, no postinstall scripts. Install and use immediately.

Performance

pdf-oxide-wasm is built on a Rust PDF parser compiled to WebAssembly. The Rust core (pdf_oxide) achieves 0.8ms mean extraction time across 3,830 test PDFs with a 100% success rate — the fastest PDF text extraction library available in Rust. The WASM compilation preserves near-native performance without garbage collection overhead or child process spawning.

Full Documentation

Complete guide with examples: Getting Started with WASM

Rust library documentation: docs.rs/pdf_oxide

License

MIT OR Apache-2.0