Documents · combine images
Combine images into one PDF
Many portals want everything in one PDF rather than as separate image files: your photograph, your signature, and the certificates, in a stated order. This tool assembles them into a single PDF, and will bring the whole document under a size limit if the portal sets one.
Everything happens in your browser. Your documents are never uploaded, and no copy exists anywhere but on your own device.
Your file is processed inside this browser and is never uploaded. There is no server involved, so nothing is stored or transmitted.
| Setting | What it does |
|---|---|
| Page size — A4 | A standard A4 page with the image centred and a margin around it |
| Page size — matches image | The page takes the shape of the image, so nothing is padded |
| Maximum file size | Compresses until the finished PDF fits under your chosen ceiling |
| Order | Move any page earlier or later before building |
| Format | Standard PDF, readable by any viewer |
Photographs are embedded as JPEG, which is what keeps the document small enough for a tight limit.
When a portal wants one file
Upload fields that accept a single document are common, and some portals specifically ask for a PDF rather than an image. This tool covers that case: add the images in the order the portal asks for and build one file.
It is the usual pattern for admission applications, where a photograph and a signature must sit in one document alongside a marksheet, and for document-verification steps that want a single combined file.
Choosing a page size
A4 is the safer choice for anything that will be printed or read as a document. The image is scaled to fit inside the margins and centred, so nothing is cropped and the proportions are never changed.
Page matches the image drops the margins entirely and makes a page in the shape of the picture. That is useful for a photograph being submitted on its own, where A4 would leave a great deal of white space, but less useful for a document you may want to print.
Neither option ever stretches an image. A photograph that is taller than it is wide stays taller than it is wide.
Meeting a size limit
If you choose a limit, the tool compresses every image and then measures the assembled PDF. If the result is still over, it tightens the compression and rebuilds, repeating until the document fits or it reaches the point where the pages would stop being readable.
The readout tells you the finished size against your limit, so you can see how much room you have. If it reports that the limit could not be met, removing a page or starting from smaller source images will get there — the tool will not hand you a file over the limit without saying so.
Order and quality
- Use the arrows to put pages in the order the portal expects. Order matters more often than people assume on document-verification uploads.
- Start from the highest-resolution originals you have. The tool can only reduce quality, never recover it.
- Photographs of documents are fine, but a flat scan is better. An angled photo wastes bytes on perspective and shadow.
- If a portal also caps the number of pages, check before building rather than after.
What this tool does not do
It does not compress a PDF you already have. Reading an arbitrary PDF means parsing cross-reference tables, compressed object streams and image filters, and getting that wrong produces a silently corrupt file — which, on a certificate you are submitting as evidence, is a serious failure.
If you need to shrink an existing PDF, the guide on bringing a PDF under a limit covers how to do it safely. This tool is for building a new document from images, where nothing existing can be damaged.
Questions people ask
Are my documents uploaded?
No. The PDF is assembled in your browser and handed straight back to you. There is no server involved and no copy is stored anywhere.
Can I compress a PDF I already have?
No, and deliberately so. Reading an arbitrary PDF safely needs a full parser, and a parser that guesses wrong produces a corrupt file. This tool builds new documents from images, where there is nothing to damage.
Why is my PDF larger than the sum of the images?
Each page carries a small amount of structure — a page object, an image object and a content stream. It is around a kilobyte per page, which is negligible unless you are close to a very tight limit.
Will the images be stretched to fit A4?
No. They are scaled to fit inside the margins while keeping their proportions, and centred. Nothing is cropped or distorted.
What order do the pages come out in?
The order shown in the list. Use the up and down arrows to change it before building. The list follows the order you selected the files in.
Can I mix photographs and scanned documents?
Yes. Any mix of JPEG, PNG and WebP images works, in any order. Documents are usually better scanned flat rather than photographed at an angle.
How small can it go before the pages become unreadable?
That depends on the source. Text needs more care than a photograph. The tool keeps reducing while it can, and tells you plainly if your limit could not be met rather than quietly handing over a file that will be rejected.