JPG to PDF converter — combine images into one PDF

Why combine images into a PDF instead of sending them separately

• Recipient ergonomics. One PDF opens in one click, scrolls through in one thumb-swipe, and prints in one command. Three PNGs are three clicks, three windows, and a question about which one comes first. For anyone reviewing a dozen of your submissions a day, that friction adds up.
• Order preservation. The recipient sees the pages in the order you intended — first the utility-bill total, then the breakdown, then the supporting screenshot. PNGs in a folder sort alphabetically by filename, which is rarely the order you meant.
• Universal format. Every device, every operating system, every email and ticketing system handles PDFs the same way. PNG support is technically universal too, but high-DPI PNG attachments occasionally trip phone-side previewers, and HEIC images from iPhones famously do not open on the Windows-laptop end of a B2B email exchange.
• Smaller total size in most cases. A PDF wrapping a set of JPEGs is roughly the sum of the JPEGs plus a small fixed overhead. For PNG inputs, the same is true. The bundled file is rarely larger than the sum of the originals and is easier to compress further if needed.

Step-by-step: combine JPG / PNG images into one PDF

The ScoutMyTool JPG to PDF tool lives at scoutmytool.com/pdf/jpg-to-pdf. Runs entirely client-side via pdf-lib — images are embedded locally and the bundled PDF is delivered as a download.

1. Decide the order before you drop. The tool preserves drop order, so think about page sequence first. If you have a stack of photo files and want them in a specific order, rename them with "01-", "02-", "03-" prefixes — most browsers sort multi-file drag-drop alphabetically, so the numeric prefix makes the order deterministic.
2. Open the tool and drop your images. Up to 50 files per batch, JPG / JPEG / PNG accepted. The dropzone shows filename and size for each image as it lands; if you accidentally drop the wrong file, remove it before clicking the action button. Each image is capped at 100 MB; pre-shrink anything larger.
3. Pick the page size. Three options:
   • Match image (default) — one image, one page, no resize. The PDF page dimensions equal the image dimensions. Best for photos, screenshots, and anything where you want the original aspect ratio preserved with zero whitespace.
   • A4 (210 × 297 mm). Each image is fitted into an A4 page, centred, with whitespace around it where aspect ratios differ. Best for international print workflows (Europe, Asia, most of the world outside the US).
   • US Letter (8.5 × 11 in). Same as A4 but US-letter dimensions. Best for US printers, US legal / business workflows.
4. If you picked A4 or Letter, pick the orientation. Portrait (default — taller than wide) or Landscape. For a mix of orientations, A4/Letter forces every page to the same orientation; if you want some pages portrait and some landscape, use "Match image" mode instead — each page follows its source image's aspect ratio.
5. Click "Convert to PDF". The tool walks each image, reads its EXIF orientation flag if present (phone-camera photos almost always have one; flag values 1–8 are defined in the Exif specification¹), rotates the image to match the EXIF intent, then embeds it into a fresh in-memory PDF via pdf-lib's embedJpg or embedPng calls. The download starts automatically.
6. Verify the output before sending. Open the downloaded PDF, scroll through, confirm the page order matches what you wanted and that no photo came out sideways. If a phone photo is rotated wrong (rare but possible — happens when the source image was edited by an app that stripped the EXIF tag), re-rotate the source image in any photo app and re-run.
7. If a JPG is rejected with "CMYK". The image is in the print-industry CMYK colour space that the PDF JPEG embedder does not support. Convert to RGB or sRGB in any photo tool (Preview, Photoshop, GIMP) and re-run. The error message names the specific file and gives the quickest fix path for each major editor.
8. For batches over 50 images. Split into batches of ≤50, run the tool once per batch, then combine the resulting PDFs via Merge PDF. The merge tool also preserves order, so a batch-of-50 workflow produces an output indistinguishable from a single-pass conversion of all images.

How ScoutMyTool compares to Smallpdf, iLovePDF and PDF2Go

All four offer JPG-to-PDF conversion. The meaningful differences: free-tier daily caps, EXIF orientation handling quality, error messages on edge cases (CMYK, oversized images), and whether your photos are uploaded.

Third-party gating, free-tier caps, and feature availability taken from each vendor's public product pages as of May 2026 and may change.

Five practical tips for cleaner bundled-image PDFs

• Crop before bundling. A photographed receipt with three inches of dark countertop around it embeds as a huge image with most pixels wasted. Cropping in the phone's built-in editor drops file size 3–5× and makes the receipt actually readable in the PDF.
• Use the "Match image" mode for photos. Forcing a wide landscape photo into a portrait A4 page leaves two huge bars of whitespace and shrinks the actual content. The recipient sees a tiny photo on a mostly-blank page; the original aspect ratio is way friendlier.
• Use A4 / Letter for receipts that will be printed. Counter-rule: when the output is going to be printed (for an expense report, an audit, a paper file), pick A4 or Letter so the receipt prints at a predictable size. Save "Match image" for digital-only viewing.
• Run Compress PDF afterwards for size-sensitive sends. The bundled PDF is essentially the sum of the JPEG / PNG inputs plus overhead. If you need it smaller for an email cap, run the output through Compress PDF — image-heavy PDFs shrink 3–5× at default quality with negligible visible loss.
• Add OCR if the bundle is a stack of paper scans. The combined PDF is a pile of pictures with no text layer; you cannot search for "energy charges" inside it. Run the bundle through PDF OCR to add a searchable text layer — useful for receipt archives and any "I need to find this charge later" scenario.

Related PDF tools on ScoutMyTool

• JPG to PDF — the tool this guide is about: combine images into one PDF.
• PDF to JPG — the reverse operation: render each PDF page as a JPG.
• Merge PDF — for batches over 50 images: bundle in chunks and merge.
• Compress PDF — shrink the bundled output before emailing.
• PDF OCR — make a bundled-scan PDF searchable.
• PDF Editor — annotate or reorder bundled images after conversion.
• Rotate PDF — fix sideways images after bundling (EXIF-stripped sources).

Frequently asked questions

Can I drop PNG files too, or only JPG?

Both. The tool is named "JPG to PDF" because that's the most common search query, but it accepts JPG, JPEG, and PNG transparently — drop any mix and the tool detects each image's format from extension and MIME type. PNG with transparency is preserved when you select the "Match image" page-size mode; when you fit to A4 or Letter, transparent regions render as white because PDF pages have a white background by default. For pages that need to remain transparent for downstream compositing, leave them in PNG form and consider a different workflow.

My phone photo came out rotated 90 degrees in the PDF. Why?

Almost all phone cameras store the photo in the same physical pixel orientation regardless of how you held the phone, and tag the JPEG with an EXIF orientation flag (1-8) that tells viewers how to rotate it for display. Some PDF embedders ignore the flag, and you end up with a sideways page. The ScoutMyTool tool reads the EXIF orientation flag (Exif specification 2.31, §4.6.4) and rotates the image to match before embedding, so a phone photo taken portrait shows up portrait in the output PDF. If your output is still sideways, the photo probably has no EXIF tag (very old digital cameras, screenshots, scanner output) — re-rotate the source image in any photo app and re-run.

What's the difference between "Match image", "A4", and "US Letter"?

Match image (default) makes each PDF page exactly the dimensions of the source image — a 4032×3024 photo becomes a 4032×3024-point PDF page. Best when you want the image at its native resolution and aspect ratio, with no wasted whitespace. A4 (210 × 297 mm, the international standard) fits each image into a portrait or landscape A4 page, centred, with whitespace around it if the aspect ratios do not match. Letter (8.5 × 11 inches, the US standard) does the same with US-letter page dimensions. Pick "Match image" for photos and screenshots; pick A4 or Letter for receipts, IDs, signed-paper scans, or anything that will be printed on paper.

How many images can I combine into one PDF?

Up to 50 images per pass. For larger sets, run the tool in batches of 50 and combine the output PDFs with Merge PDF afterwards. The 50-image cap is a guard against runaway browser memory usage — embedding 100+ high-resolution photos into a single in-memory PDF can use multiple gigabytes of RAM and crash the tab. Per-image cap is 100 MB; if any single image exceeds that, the tool fails fast with a clear message naming the file rather than silently producing a corrupt output.

In what order do the images appear in the output?

In the order you dropped them into the tool. The dropzone preserves drop order, and the PDF is built page-by-page in that same sequence. If you need a specific order, drop the images one at a time, in the order you want them — or rename the files with a "01-", "02-", "03-" prefix before dropping all of them at once, since multi-file drag-drop sorts files by filename alphabetically in most browsers.

Is my image uploaded to your server?

No. The conversion runs entirely in your browser using pdf-lib. Your images are loaded into a sandboxed memory buffer, embedded into an in-memory PDF document, and the result is delivered as a download. Nothing leaves your device — verify in the browser network tab if you want independent confirmation. This matters for sensitive scans (IDs, contracts with signatures, medical documents) that you would never want uploaded to a random web service.

My JPG is CMYK — why does the tool reject it?

CMYK JPEGs (or YCCK, the four-component variant) are a print-industry format that the standard PDF JPEG embedder used by pdf-lib does not support. The tool detects the colour-component count up front and gives you a clear error naming the file rather than failing silently with a corrupt output. The fix: re-export the JPEG in RGB or sRGB. In macOS Preview: Tools → Adjust Color → switch the profile to sRGB. In Photoshop: Image → Mode → RGB Color. In any free tool like GIMP: Image → Mode → RGB. Re-run the tool with the RGB version and it embeds cleanly.