@namahapdf/pptx - In-Browser PowerPoint (.pptx) Engine for JavaScript

@namahapdf/pptx is a headless PowerPoint engine that runs entirely in the browser - parse a .pptx, render slides to canvas, edit with faithful write-back, export to PDF, and project a deck into an AI-readable model. It's an in-house OOXML implementation (no LibreOffice, no cloud conversion service), built for the rare capability most PDF/Office SDKs skip: editing a PowerPoint deck client-side and saving a byte-faithful .pptx back, with no repair dialog on open.

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npm i @namahapdf/pptx

import {
  PptxEditSession,
  renderSlide,
  applyPptxPlan,
  configureLicense,
} from '@namahapdf/pptx';

// Apply your license key (without one, exports are watermarked + features limited).
configureLicense({ licenseKey: 'YOUR_KEY' });

// Load a deck into an editing session, edit by intents, save a faithful .pptx.
const session = await PptxEditSession.load('deck.pptx', bytes);
await session.apply([
  { op: 'replace-text', anchor: { fmt: 'pptx', slidePart: 'ppt/slides/slide1.xml', shapeId: '2' }, newText: 'Q3 Review' },
]);
const editedBytes = session.bytes;              // still a valid .pptx

Features

• Parser - .pptx → a resolved slide model (theme/master/layout composed), fully client-side
• Renderer - high-DPI slide raster + positioned, selectable text segments
• Faithful write-back - edits apply as surgical XML splices on the original package, so everything an edit doesn't touch is preserved byte-for-byte
• PDF export - hybrid raster + real selectable text, no LibreOffice
• AI-ready - a small, JSON-serializable EditPlan vocabulary (replace-text, move-shape, add-slide, replace-image, …); validate with validateEditPlan and the same plan an LLM emits is the plan the UI emits
• TypeScript-first, ESM + CJS builds

Why teams pick @namahapdf/pptx

Client-side PowerPoint editing is rare. Most document SDKs that support Office formats lean on server components or offer view-only rendering. @namahapdf/pptx edits and re-saves a real .pptx entirely in the browser.

Round-trip fidelity by construction. The parsed slide model is a render view, not the source of truth - the writer always re-opens the original zip/XML and splices only what an EditPlan intent changed, so untouched slides, masters, and layouts are byte-identical to the source file.

On-device by architecture. Parsing, rendering, and editing all run client-side - no upload step, no cloud dependency for the common path.

One intent vocabulary for humans and AI. The UI and an LLM agent emit the exact same EditPlan JSON against the exact same apply path - there's no separate, riskier "AI editing" code path to maintain or trust.

API surface

• PptxParser - .pptx → a resolved slide model
• renderSlide - a slide → a high-DPI background raster + positioned text segments
• applyPptxPlan / PptxEditSession - write-back (intent-sourced, undo/redo)
• toStructure - a semantic projection for Markdown / RAG / AI
• pptxToPdf - export a deck to PDF

The full API reference and edit-intent contract live in the PowerPoint SDK docs.

Licensing

Free to install and use - trial mode renders a watermark and gates premium features. A per-domain license key removes the watermark and unlocks the full feature set. Get one at pdf.namahatech.com/sdk; pricing at pdf.namahatech.com/pricing. A ready-made React slide editor (@namahapdf/react) is planned.

Related packages

| Package | What it is | |---|---| | @namahapdf/pptx | This package - the headless PowerPoint engine | | @namahapdf/core | Headless PDF engine | | @namahapdf/sheets | Headless Excel (.xlsx) engine | | @namahapdf/react | React <NamahaEditor> (PDF today) |

FAQ

Does this upload .pptx files to a server? No. Parsing, rendering, and editing all run in the browser. Nothing is uploaded for the common path.

Will edited decks open in PowerPoint without a repair-dialog warning? Yes - that's the core design constraint. Write-back is byte-preserving on anything an EditPlan doesn't explicitly touch; npm run audit:pptx in the source repo is the fidelity regression gate.

Can an LLM agent edit a deck with this? Yes - EditPlan is a small, Zod-validated JSON schema (validateEditPlan/editPlanJsonSchema) designed to be handed to an LLM as a tool definition; the agent emits the same intents the UI does.

Is there a free tier? Yes. It's free to install and use in trial mode (watermarked, feature-limited). See pdf.namahatech.com/pricing for licensed tiers.

License: proprietary (see LICENSE). A license key from pdf.namahatech.com/sdk removes the trial watermark for production use. Questions or enterprise inquiries: same link.