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Convert images to PDF online without uploading your documents to any server

Combine photos and scanned documents into a single PDF directly in your browser, without your files ever leaving your device.

2026-07-027 min

You need to merge several scanned documents into a single PDF to send by email. Or combine photos of receipts for an expense report. Or group images of your ID, pay stubs, and a contract to upload to a government portal that only accepts a single PDF file. It is an everyday need, and most online tools that handle it have a serious problem that goes unnoticed: they upload your documents to their servers.

The privacy problem almost nobody sees

Think about what you typically convert to PDF. It is rarely vacation photos. It is usually documents with personal information: IDs, passports, invoices, bank statements, pay stubs, medical prescriptions, contracts. Information you would not want ending up in the hands of a third party.

And yet, the vast majority of online converters work exactly that way: you upload your images to their server, the server generates the PDF, and sends it back. Your documents pass through infrastructure you do not control, managed by a company whose data policies you probably never read. Some store files for hours. Others claim to delete them immediately, but you have no way to verify that.

The irony is that generating a PDF from images is an operation your own browser can perform without sending anything anywhere. There is no technical reason for your documents to travel to a server.

Most common use cases

  • Government portals and official paperwork: many online submission forms for tax agencies, social services, and local government offices require you to upload a single PDF containing multiple documents (ID front and back, proof of payment, signed form).
  • Expense reports: photos of receipts and invoices grouped into an organized PDF for accounting or human resources.
  • Sending documentation by email: instead of attaching six separate images, you send a single PDF that the recipient can open and review sequentially.
  • Portfolios and albums: combining work samples, designs, or photos into a browsable document.
  • Home digitization: scanning documents with your phone camera and grouping them into a PDF for your records.

How to convert images to PDF step by step

With the image to PDF tool from SocialShrink, the process is straightforward and everything happens in your browser:

  1. Open the tool. You do not need to create an account or install anything.
  2. Drag in all the images you want to include in the PDF. You can add JPG, PNG, or any image format your browser supports.
  3. Reorder the images if needed. The order they appear in will be the page order of the PDF.
  4. Choose the page size (A4 is the international standard for documents, but other options are available including US Letter).
  5. Generate and download the PDF. The file is created directly in your browser and downloaded to your device.

At no point is anything uploaded to any server. Your images are processed in the browser's memory, the PDF is built locally, and it is downloaded. When you close the tab, no trace remains.

Tips for a good result

The quality of the PDF depends directly on the quality of the images you put into it. A few practical tips:

  • Scanning resolution: if you scan documents with your phone, make sure there is good lighting and that the text is legible when you zoom in on the photo. A blurry image will still be blurry inside the PDF.
  • Orientation: if you mix vertical and horizontal photos, check that each one ends up in the correct orientation. You can use the rotate image tool before generating the PDF if any photo came out sideways.
  • Pre-cropping: if the photo of your document has a lot of excess margin (the desk, your fingers holding the paper), crop it first with the crop image tool. The PDF will look much cleaner and more professional.
  • Page size: for most international documents, A4 (210 x 297 mm) is the standard. If you are sending documents within the United States or Canada, Letter size (8.5 x 11 inches) is more common there.
  • Pre-compression: if the resulting PDF is too large to upload (many government portals cap uploads at 5-10 MB), compress the images before converting them.

Image-based PDF vs PDF with OCR: an important distinction

When you convert images to PDF, the result is exactly that: a PDF containing images. The pages look like the original document, but the text that appears in them is not selectable or searchable. It is a photo inside a PDF.

A PDF with OCR (optical character recognition) is different: software analyzes the image, detects the letters, and creates an invisible text layer on top. This allows you to copy text, search for words within the document, and lets screen readers read it aloud.

For most everyday uses (sending documentation, archiving receipts, submitting expense reports), an image-based PDF is perfectly valid. OCR is only necessary if you need to search for text within the document or extract data programmatically. It is worth knowing that OCR requires complex processing and, in most online tools, involves uploading your document to a server, which multiplies the privacy risk.

What to do if the PDF is too large

If your original images are high resolution (12-megapixel phone photos, for example), the resulting PDF can be quite heavy. To reduce it, compress the images before putting them into the PDF with the image compression tool. For scanned documents, a quality of 80-85% is usually more than enough: the text remains perfectly readable and the file size drops significantly.

The reverse direction: from PDF to images

Sometimes you need the opposite: extracting pages from a PDF as individual images, for example to include a page from a contract in a presentation. For that, there is the PDF to image tool, which also runs entirely in your browser.

Frequently asked questions

Are my documents uploaded to any server?

No. All processing happens in your browser. The images are read into local memory, the PDF is built using JavaScript on your own device, and you download the resulting file. No data leaves your computer or phone at any point. This is especially relevant when you are working with sensitive documents like IDs, pay stubs, or medical records.

How many images can I combine into a single PDF?

There is no fixed limit, but the more high-resolution images you include, the more memory your browser consumes. For typical documents (5-20 pages) you will have no issues. If you need to combine many images, compressing them beforehand helps prevent the browser from running out of memory.

Can the resulting PDF be edited?

The PDF contains images, not editable text. You can view the images, print them, and share the file, but you cannot select or modify the text that appears in the photos. For that you would need OCR software to convert the image into recognizable text, which is a separate process.

What page size should I choose?

For most international use, A4 is the standard option (210 x 297 mm). It is the size expected by most government portals, institutions, and companies worldwide. If you need to send documents within the United States or Canada, Letter size (8.5 x 11 inches) is the norm there. If you are unsure, A4 is always a safe bet for international correspondence.

SocialShrink
Independent studio · Barcelona
Privacy-first creator tools. Compress, convert and adapt your images and videos for every social network — everything is processed in your browser, nothing uploaded.
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