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How to Convert JPG to PDF

By Clioos 团队

The free offline way is Pillow: each JPG becomes one PDF page, no upload, no account. Tested 2 November 2026 with Pillow 10.2.0 — two sample JPGs (1240x1754 at 1,109,508 bytes and 800x1000 at 405,964 bytes) became a 2-page PDF of 1,148,550 bytes. Clioos does not offer a JPG-to-PDF tool — this guide teaches the method.

At a glance

Clioos has no JPG-to-PDF tool. The method below runs on your own computer with free, open-source Pillow — no upload, no account.
Each JPG becomes one PDF page, in file order. Two JPGs in, two pages out in the test.
The output PDF was smaller than the JPGs combined (1,148,550 vs 1,515,472 bytes) because Pillow re-encodes the images — keep your originals.
Page size follows the image dimensions at the resolution you set (150 DPI in the test).
A JPG-to-PDF conversion does not OCR anything: the PDF pages are pictures, not searchable text.

Steps

Install Pillow: pip install pillow (Pillow 10.2.0 in the test).
Run: Image.open(first).save("out.pdf", "PDF", save_all=True, append_images=rest, resolution=150.0).
Verify: open the PDF and count the pages (2 in the test), then compare sizes — input 1,515,472 bytes, output 1,148,550 bytes.
If a page looks wrong, re-run from the original JPGs — never re-convert the PDF.

Worked example (tested 2 November 2026)

Test files: two generated sample JPGs (photo-like gradients, saved at JPEG quality 85). Method: Pillow 10.2.0, one image per page, 150 DPI.

File	Dimensions	Size
page1.jpg	1240x1754	1,109,508 bytes
page2.jpg	800x1000	405,964 bytes
combined.pdf (output)	2 pages	1,148,550 bytes

Total JPG input was 1,515,472 bytes; the PDF came out smaller (1,148,550 bytes) because Pillow re-encodes the images. Page count matched the image count exactly: 2 in, 2 out.

Which method to pick

Offline (Pillow, this guide): free, private, scriptable. Needs Python installed.
Browser converter: no install, drag and drop — but your images upload to a vendor server.
OS print to PDF: built into most systems for single images, but page control is weaker than a script.

What it can't do

No Clioos tool for this: Clioos does not offer JPG-to-PDF conversion. The method above is the free offline route.
No OCR: the PDF pages are pictures. Text in the images is not searchable or selectable.
Quality can shift: re-encoding can soften fine detail. Keep the original JPGs.
No editing: this only packs images into pages. Cropping, rotating or reordering means editing the images first.
No encryption: the output PDF is unprotected; password protection needs another tool.

Free alternatives, honestly compared

Pillow: free and open source, offline, exact page control. Requires a Python install.
Browser converters: free up to a daily limit, no install — but files leave your computer.
OS print to PDF: free and built in, best for one image at a time.

Frequently asked questions

Is it free to convert JPG to PDF?

Yes, with Pillow — free and open source, no per-file charge. Browser tools are free up to a daily limit.

Will the PDF be smaller than the JPGs?

Not necessarily. In the test it was smaller (1,148,550 vs 1,515,472 bytes) because the images were re-encoded — but with already-compressed JPGs the PDF can come out larger. Check the output size.

Can I control the page size?

Yes: page size follows the image dimensions at the resolution you set (150 DPI in the test). Larger images make larger pages.

Does the PDF text become searchable?

No. JPG-to-PDF packs pictures into pages; nothing is OCRed. For searchable text, OCR the images first.