Image to PDF converter
Convert mixed image formats into one PDF with reliable output on phone and desktop.
Image formats behave differently in a PDF
JPG, JPEG, PNG, HEIC, WebP, and screenshots can all look like "images" in a file picker, but they are not equal once you place them in a PDF. Photos, screenshots, scans, and transparent graphics respond differently to compression and resizing. Choosing the right settings starts with knowing what kind of image you have.
Format comparison
| Format | Best for | Watch out for | PDF tip |
|---|---|---|---|
| JPG/JPEG | Camera photos and scanned paper | Repeated compression can soften text | Use medium compression for sharing, lower compression for print. |
| PNG | Screenshots, UI, text, simple graphics | Can be large for photos | Use slightly higher DPI for crisp text. |
| HEIC/HEIF | iPhone photos with efficient storage | Browser support varies outside Apple devices | If import fails, export as JPEG first. |
| WebP | Modern web images | Older browsers may vary | Check the preview before adding a large batch. |
| AVIF | Highly compressed modern images | Not reliable everywhere | Convert to JPEG or PNG if the browser cannot decode it. |
When mixing formats
A common real-world batch might include phone photos, screenshots, and a downloaded logo or document image. Use one page size for the final PDF so the document feels consistent. If screenshots contain small text, choose a DPI that keeps them sharp. If camera photos dominate the batch, avoid using PNG-like expectations for file size; photo detail and background texture can make the PDF larger.
Recommended settings by source
- Phone photos: 144 to 180 DPI, medium compression, Strip metadata on.
- Screenshots: 180 to 220 DPI, medium or lower compression to preserve edges.
- Receipts: 144 to 180 DPI, Fit, white background, metadata stripped.
- Print photos: 240 to 300 DPI, low-medium compression, 1-up layout.
- Mixed document pack: 180 DPI, medium compression, consistent A4 or Letter pages.
Browser caveats
Because JPEGtoPDF.io converts locally, the browser has to decode each image format. JPG, JPEG, PNG, and WebP are broadly supported in current browsers. HEIC and HEIF can work well on Apple devices but may fail on some Windows or Android setups. If a file does not preview, try converting that source image to JPEG first, then add it again.
Order and naming matter
For applications, invoices, or evidence packs, rename source files before adding them if the order matters: 01-cover, 02-id-front, 03-id-back, 04-receipt. The converter lets you reorder pages, but clear filenames reduce mistakes when you have to rebuild or audit a document later.
Quality check after export
- Open the final PDF and scan every page quickly.
- Zoom in on screenshots or small printed text.
- Check that transparent or dark images still have enough contrast.
- Confirm file size before sending or uploading.
- If one format causes problems, convert that source image separately and retry.
When to convert the source first
If one image type repeatedly fails, convert that source file before building the PDF. HEIC can be exported as JPEG from many photo apps. Screenshots can stay PNG if they contain small text. Web images can often be saved again as JPEG or PNG. Fixing one awkward source file is usually faster than weakening settings for the entire document.
Related help
Reviewed on April 29, 2026 by JPEGtoPDF.io. See About, Editorial Policy, and Privacy.