How to Convert Images to PDF Online (JPG, PNG, HEIC — Free)

Whether you're submitting scanned documents, sending photos as a professional attachment, or archiving screenshots, converting images to PDF is a routine task. This guide covers every method — browser tools, built-in OS features, and command-line options — with a clear take on when to use each.

When do you need image-to-PDF?

• Document submissions — universities, banks, and government portals almost always require PDF, not JPEG
• Multi-page scans — a scanner that produces one image per page; you need them as a single paginated document
• Professional sharing — a PDF preserves layout and doesn't accidentally get compressed by email clients or messaging apps
• Archiving photos — PDF/A is an ISO standard for long-term digital archiving
• iOS/Android screenshots — HEIC photos from iPhones need conversion before Windows users can view them

Supported formats

Convert images to PDF in your browser (DevBench)

1. Open DevBench Image to PDF
2. Drag and drop your images — JPG, PNG, WebP, HEIC, BMP, or TIFF
3. Reorder pages by dragging thumbnails into the desired sequence
4. Choose page size (A4 is the global standard; Letter is common in North America)
5. Click Convert to PDF and download

All processing happens in your browser with pdf-lib. No images are uploaded. Works with multiple images at once — one image per page.

Convert on macOS (built-in, no install)

For a single image: open it in Preview → File → Export as PDF. Done.

For multiple images: select all files in Finder → right-click → Quick Actions → Create PDF. macOS creates a multi-page PDF in the same folder with images sorted by filename.

Convert on Windows 10/11 (built-in)

1. Open the image in the Photos app
2. Press Ctrl + P to print
3. In the printer dropdown, select Microsoft Print to PDF
4. Choose orientation and click Print — then save the PDF

For multiple images, select all in File Explorer → right-click → Print → choose Microsoft Print to PDF. Windows will ask for page layout and create a multi-page PDF.

Convert with ImageMagick (command line)

# Single image
convert photo.jpg output.pdf

# Multiple images to one PDF
convert page1.jpg page2.jpg page3.jpg combined.pdf

# With quality control (lower number = smaller file)
convert -quality 80 photo.jpg output.pdf

Install ImageMagick with brew install imagemagick (macOS) or apt install imagemagick (Ubuntu). For HEIC files on macOS you also need brew install libheif.

Note: some Linux systems restrict ImageMagick's PDF output by default due to security policies. Edit /etc/ImageMagick-6/policy.xml and change the PDF policy from none to read|write if you get a "not authorized" error.

Tips for better output quality

• Page size matters — A4 (210×297mm) is standard globally; if your images are portrait photos they'll fit correctly. Landscape photos may need a rotated page setting.
• DPI for scans — 150 DPI is readable; 300 DPI is the standard for document archival. Higher DPI = larger file.
• Transparent PNG — transparency is not supported in PDF. It renders as white. If you need the transparent background preserved, convert to PNG with a coloured background before converting to PDF.
• HEIC to PDF — browsers natively support HEIC → PDF now; if your tool doesn't, convert HEIC → JPEG first using macOS Photos or a converter.