gPdf Docs

Public API documentation, executable examples, and comparison materials for the gPdf PDF rendering service.

gPdf turns a JSON DocumentRequest into a PDF document at the edge in 3–5 ms. Rust + WebAssembly running on Cloudflare Workers. No browser, no cold start, no document persistence.

• 🌐 Service — gpdf.com
• 💵 Pricing — $5 / month for 100K pages (Basic tier); free trial 100 pages / day
• 📰 Blog — gpdf.com/blog
• 🛠 Changelog — gpdf.com/changelog · also mirrored in CHANGELOG.md
• 🛡 Status — gpdf.com/status

Quick example

curl -X POST "https://api.gpdf.com/api/v1/pdf/render" \
  -H "Authorization: Bearer sk_live_..." \
  -H "Content-Type: application/json" \
  -d @examples/invoice.json \
  -o invoice.pdf

See examples/ for ready-to-run JSON payloads.

Documentation

Doc	Endpoint	When to use
API Reference	POST /api/v1/pdf/render	Full DocumentRequest with pages, elements, coordinates, tables. Use when you need pixel-level control.
Template API	POST /api/v1/template-render	template_id + data array. Use when you have a published template and only business data changes per call.
E-Invoice API	POST /api/v1/e-invoice/render	Factur-X / ZUGFeRD hybrid invoices: PDF/A-3 with embedded EN 16931 XML. For EU e-invoicing mandate compliance.
Template Authoring	—	Author reusable templates that bind business data.

Verified facts

• Render latency (p50): 3 ms for a 1-page A4 invoice (median across 1K invocations on a Cloudflare Workers isolate).
• Pricing: $5 / month for 100,000 pages (Basic); equivalent to $0.00005 per page.
• PDF/A profiles: PDF/A-1b · 2b · 3b · 4 selectable per request.
• In-memory document lifetime: ~4 ms. Stateless: the buffer exists only inside one V8 isolate for the request, then is freed. No persistence, no document store.

Comparisons

Performance + capability head-to-heads against other PDF tools:

• gPdf vs Puppeteer — headless Chromium vs edge-native WASM
• More comparisons coming (DocRaptor, PDFShift, Anvil, Prince, wkhtmltopdf, PDFKit, ReportLab).

Capabilities at a glance

• Layout: pages[], elements[], x/y in millimetres, x_anchor for content_right alignment.
• Text: paragraph, list, page_break blocks. Variables resolved post-layout: page, total_pages.
• Tables: row-span across pages, repeating headers, alternate fill, double-line borders.
• Stack/block: invoice-tail subtotal/total blocks that follow a paginated table.
• Layers: background, watermark (algorithmic tiled), and stamp (last-page approval marks).
• Barcodes: 30+ vector symbologies — QR, GS1-128, PDF417, DataMatrix, Aztec, MaxiCode, ITF-14, SSCC-18, UPS S10, Code 128 family, EAN/UPC family.
• CJK: NotoSans CJK embedded with automatic fallback. No OS-level font install required.
• PDF/A: 1b · 2b · 3b · 4 · UA-1 selectable per request.
• E-invoice: Factur-X / ZUGFeRD attachment streams ride on PDF/A-3. Aligns with EN 16931 mandates rolling across the EU through 2026 and 2027.
• Output: binary (Content-Disposition: inline) or file (Content-Disposition: attachment).

Where it runs

Inside Cloudflare Workers V8 isolates. No Chromium container, no Lambda warming, no document persistence after the request. Same input renders to a byte-identical PDF across isolates.

About this repo

This repo is the public documentation surface of gPdf:

• ✅ API contract (request shapes, error codes, limits)
• ✅ Executable JSON examples
• ✅ Performance comparisons
• ✅ Changelog mirror

The gPdf rendering engine source code is not public. The marketing-site source (Astro app, blog, hreflang infrastructure) is also kept private. This repository contains the public-facing API contract and integration material only.

See CONTRIBUTING.md for issue + PR guidelines.

License

Documentation content licensed under MIT.