How the JPG to PDF Converter Works
This converter uses jsPDF, a mature JavaScript library that builds PDF files entirely in your browser. When you drop images into the converter, the browser reads them locally. jsPDF creates a new PDF document, places each image on its own page with your chosen layout, compresses the result, and hands it to you as a download.
At no point do your images leave your device. Open your browser's DevTools (F12), switch to the Network tab, and start a conversion. You'll see zero network requests during the entire process.
Why Convert JPG to PDF Client-Side?
Most online JPG to PDF converters work by uploading your images to a server, converting them there, and sending back a link. This means your images — family photos, scanned documents, medical records, ID cards — sit on a stranger's server, sometimes for days or weeks. Privacy policies change, servers get breached, and data gets scraped for AI training datasets.
With PrivateConvert, the conversion is architecturally enforced privacy. The code that builds your PDF doesn't have a network module — it literally cannot send your files anywhere. This is not a promise; it's a mathematical constraint of the code.
Features at a Glance
- Multiple images → Single PDF — drag in as many JPGs or PNGs as you need. Each becomes a page.
- Drag-to-reorder — arrange your pages by dragging thumbnails before conversion.
- Three page sizes — A4, Letter, and Legal with portrait or landscape orientation.
- Flexible layout — Fit (no crop), Fill (cover the page), and Stretch (fill completely).
- Adjustable margins — 0, 5, 10, or 20 mm margins for professional-looking documents.
- Quality control — Lossless, high, medium, or low quality to balance file size.
- Supports JPG, PNG, WebP, BMP, TIFF, and SVG — nearly every image format your browser can open.
When to Use JPG → PDF
Converting images to PDF is useful in several common scenarios:
- Document scanning — scan pages as JPG on your phone, combine them into a single PDF.
- Photo portfolios — compile your best shots into a clean, printable PDF.
- Work receipts — photograph receipts and invoices, bundle as PDF for expense reports.
- School submissions — combine handwritten assignments photographed as images into a single file.
- Legal documents — convert scanned contract pages into a searchable-format PDF.
- ID verification — combine front and back scans of an ID into one PDF without uploading anywhere.
Privacy Comparison: PrivateConvert vs Online Converters
Every major "free" online converter (zamzar.com, smallpdf.com, ilovepdf.com, cloudconvert.com) uploads your files to their servers. Their privacy policies disclose data retention periods ranging from "a few hours" to "up to 30 days." Some reserve the right to analyze uploaded content to improve their services.
PrivateConvert is different: your files never leave the browser. This is not a policy choice — it's how the code works. You can verify it yourself by inspecting the page source or watching the Network tab during conversion. There are no API endpoints, no database connections, and no server-side processing.
Tips for Best Results
- Use Lossless quality for documents where text must remain sharp.
- Use Fit mode to avoid cropping any part of the image.
- Use Fill mode to avoid white borders when images don't match the page ratio.
- Drag to reorder before converting — the conversion order matches your preview list.
- Name your output file — the filename field defaults to the first image's name.
Browser Compatibility
The JPG to PDF converter works in all modern browsers: Chrome 90+, Firefox 90+, Safari 15+, and Edge 90+. It uses the HTML5 Canvas API, FileReader API, and standard drag-and-drop events — all available in any up-to-date browser without extensions. No WebAssembly or plugins required.
Technical Details
This tool uses jsPDF 2.5+, an open-source PDF generation library. Images are loaded as data URLs via the FileReader API and rendered onto PDF pages using the canvas-based image pipeline. JPEG compression is applied at your chosen quality level using the browser's native Canvas 2D API. The entire conversion runs in a single thread on your CPU, and memory usage scales with the number and resolution of input images.
$ openssl dgst -sha256 /dev/network ☐ — No network activity. No server logs. No trace.