Every time you open an official portal — a university, a government agency, an embassy, or a hiring company — you find almost the same line: "Upload a photo of your ID and a photo of your passport as a PDF." The problem is that the pictures on your phone are JPG or PNG, and what is wanted is a single, organised file with one page per document.
The answer is not uploading each picture to a different site for it to store on its servers. The answer is merging the images into one PDF on your own device, then uploading the result yourself — after you know exactly what is happening to your files.
In this guide we walk through turning images into a PDF for official portals step by step, why it matters that the processing happens inside your browser, and the tool's real limits so an error message does not catch you in the middle of an application.
What do official portals actually ask for?
Saying "attach the documents as a PDF" usually means three things: one file instead of ten scattered pictures, one page per document so nothing gets mixed up, and a fixed order that the officer reads from top to bottom. Some organisations add a fourth condition written on the help page rather than in the upload form: A4 page size.
That is why good tools let you choose the page size, not just the number of images. Here is the difference between the two sizes.
A4 or image size?
The two options look similar, but they serve completely different purposes:
| Criterion | A4 | Image size |
|---|---|---|
| Page size | A4 — 210 × 297 mm | Exactly the image's own dimensions |
| Margins | Even margins on all sides | No margins at all |
| Best for | Printing, official documents, portals | On-screen viewing and sharing pictures |
| Look of an ID photo | Centred on a white page | Fills the page completely |
| Page orientation | Switches automatically with the image | Matches the image exactly |
| File consistency | Every page the same size | Every page a different size |
The practical rule: if the file will be uploaded to an official portal or printed, choose A4. If it will only be viewed on a screen, image size is lighter and faster.
How to turn images into a PDF — step by step
- Open the Images to PDF tool on TaskDo. No sign-up, no account, no software to install.
- Pick your images from your device, or drag and drop them into the drop area. You can add one picture or ten in the same run.
- Reorder the images with the arrows until the order is what you want in the final file. Start with the ID photo, then the passport, then the rest.
- Choose the page size: A4 for official documents, or "image size" if the file is for on-screen viewing only.
- Press "Create PDF". The processing happens inside your browser, and no image is uploaded to any server.
- Download the result under a clear name, then open it and check the order and page count before uploading it to the portal.
Reorder the images before you press "Create PDF". The order of the list inside the tool is the order of the pages in the final file — it cannot be changed after the PDF is created.
What actually happens to your images during the conversion?
A few small technical details that matter for both quality and privacy:
- JPG and PNG images are embedded as they are. They are not rewritten or compressed again, so their original quality and the sharpness of any text stay exactly as you captured them.
- Other formats are converted automatically. Any format your browser can open — WebP, or HEIC if your browser supports it — is drawn first and then embedded as a PNG image inside the page.
- One image per page. Two images are never merged onto one page, because that is the shape portals and print shops expect.
- Everything runs on your device. The images never leave your browser, so there is no server keeping a copy of them after you finish.
One point worth attention: if your images are large — and they usually are — the resulting file can become heavy and hard to upload to a portal with a maximum file size. The fix is simple: compress the images first, then turn them into a PDF.
The tool's limits you should know before you start
Every tool has limits, and knowing them in advance beats discovering them mid-application:
- Page size: A4 or image size. There are no other sizes such as Letter.
- Number of images: no limit on our side, but the practical limit is set by your device's memory. Ten high-resolution images run without trouble on any modern device.
- Supported formats: JPG, PNG and WebP, plus any format your browser can open.
- Page orientation: determined automatically from the image's dimensions — a portrait page for a portrait image and a landscape page for a landscape one.
And if your task exceeds what a browser can comfortably handle — for instance hundreds of images in one go — split the work into batches and merge the resulting files into one.
Tips for images that are accepted the first time
- Name your files in sequence before uploading: 01-id-card, 02-passport, 03-birth-certificate. This makes the order inside the tool obvious and reduces the chance of a mistake.
- Choose A4 for official documents even when the application does not mention the size. A file with uniform page sizes reads faster and prints without surprises.
- Check the order before creating the file, and check the final file after downloading it. One minute here saves a rejected and re-submitted application.
- Compress large images first if the portal has a maximum total file size.
- Take the pictures in good light against a light background, and make sure all four corners of the document are visible before you shoot — converting to a PDF does not improve an unclear photo.
- Keep the original images as they are. The tool produces a new file and never edits or deletes your pictures.
Frequently asked questions
Which image formats are supported?
The tool supports JPG, PNG and WebP, plus any format your browser can open. Other formats are converted automatically to PNG before being inserted into the page.
Is image quality preserved?
Yes. JPG and PNG images are embedded as they are, without re-compression, so they keep their original quality. Other formats are drawn and then embedded as a PNG image.
Can I place more than one image on a single page?
No. The tool places one image per page, which is the best shape for official documents because it prevents documents from being mixed together.
Are my images uploaded to any server?
No. The processing happens entirely inside your browser and the images are never sent to any external server. That is why you can convert sensitive documents safely.
Is the tool free? Do I need to sign up?
The tool is completely free and needs no account or sign-in. Open the page and use it immediately.
Does it work on a mobile phone?
Yes. The tool works on any device with a modern web browser, and you can pick the images straight from your phone's gallery.
What if the resulting file is larger than the portal's limit?
Compress the images first with the Compress Images tool, then convert them to PDF.
Can I change the order of the images after creating the file?
No. The order of the list inside the tool is the order of the pages in the final file, so review it before pressing "Create PDF".
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Summary
Turning images into a PDF for official portals no longer needs software on your computer or a site that uploads your pictures to its servers. With the Images to PDF tool on TaskDo you place each image on its own page in a single file, at A4 size or at the image size, in the order you choose — and no image ever leaves your device.
The basic rule stays the same: your pictures are your documents, and they should stay on your device until the moment you choose to upload them.