How to merge PDF files into one for an application
By the PdfDady team · Updated · 6 min read
To merge PDF files, add them to a merger, put them in the order the form asks for, and save the result as one file. With our Merge PDF tool that takes about a minute, the pages are copied exactly as they are, and nothing is uploaded because the work happens in your browser.
The merging itself is the easy part. What goes wrong is everything around it: the order, a file that is still a photo, a locked PDF, or a merged file that is bigger than the portal allows. This guide covers those.
When you need one PDF instead of many
Application portals often give you a single upload box for a whole group of documents. "Upload all marksheets as one PDF" is a typical instruction on admission, scholarship and recruitment forms. HR teams ask for the same thing at joining: all educational certificates in one file, all experience letters in another.
Before you start, read the instruction once more and note three things:
- What goes in the file. Only what is asked for. If the box says "Class 10 and 12 marksheets", don't add your degree.
- The order, if one is given.
- The size limit and file type. These are usually printed next to the upload box or in the notification.
Merge your PDFs step by step
- Open the Merge PDF tool on your phone or computer.
- Add your PDFs. You can drop in up to 50 files, each up to 100 MB, with 200 MB in total, and you can add more later.
- Check each file. Every one shows a thumbnail of its first page and its page count, which is how you tell
scan0004.pdffromscan0007.pdf. - Put the files in order with the move up and move down buttons. Remove any file you added by mistake.
- Create the merged PDF and download it. It is saved as
merged.pdf, with all the pages of each file in the order shown.
Rename the download before you upload it. Something like Marksheets_YourName.pdf is easier for the person at the other end, and some portals tell you exactly what to call the file.
Then open it and scroll through every page once. This takes twenty seconds and catches most problems.
What order should the documents go in?
If the notification lists the documents in an order, follow that order exactly. The person checking your file is usually working down the same list.
If no order is given, oldest first is the safe choice for education documents:
- Class 10 marksheet and certificate
- Class 12 marksheet and certificate
- Semester or year marksheets, first to last
- Degree or provisional certificate
- Anything extra that was asked for, such as a caste, income or experience certificate
Keep the two sides of one document together. If the back of your marksheet has the grading key or a seal, it goes right after the front, not at the end.
If some documents are still photos
The merge tool accepts PDFs only. A photo of your Class 12 marksheet sitting in your gallery has to become a PDF first.
- For clear, straight photos, Image to PDF puts each photo on its own page.
- For photos taken at an angle or with shadows, Scan to PDF lets you straighten the page and clean it up first.
Make the PDF, then come back and add it to the merge with your other files.
Problems you are likely to hit
The merged file is over the size limit
Merging does not shrink anything. Pages are copied as they are, so the merged file is roughly the sizes of your files added together. Five scans of 400 KB each will give you about 2 MB.
If the portal's limit is lower than that, run the merged file through Compress PDF, which can aim for a target size. Check the text is still readable afterwards, especially small print like roll numbers and marks.
One of the files is refused
Password-protected PDFs can't be merged in the browser, so the tool refuses them with a message. This includes files that ask for a password when you open them (e-Aadhaar, many bank statements and salary slips) and files that open normally but have restrictions on printing or copying.
If you know the password, Unlock PDF saves a copy that opens without it, and that copy will merge. If you don't know the password, no tool can help you honestly; get a fresh copy from whoever issued the document.
One page is in the wrong place
The merge tool orders whole files, not single pages. If page 2 of one file needs to sit somewhere else, merge first and then open the result in Organize PDF, where you can drag individual pages, rotate a sideways one or delete a blank. Our guide on rearranging PDF pages goes through that.
A page is sideways
A sideways scan stays sideways after merging. Fix it before or after with the steps in how to rotate PDF pages permanently.
You only need part of a file
If your marksheet is page 3 of a 12-page PDF, don't merge all twelve pages. Pull out the page first; see how to save one page of a PDF.
What merging keeps and what it drops
| In your original files | In the merged PDF |
|---|---|
| Page content and quality | Unchanged. Pages are copied, not re-rendered |
| Selectable text | Stays selectable |
| Links inside a page | Kept |
| Bookmarks (the outline in the sidebar) | Not kept |
| Fillable form fields | May stop being fillable |
| Password protection | Not supported. The file is refused |
For scanned certificates and marksheets, none of the losses matter. They matter if one of your files is a form you filled in on screen. In that case, open the merged file and check that it still looks the way you need before you send it.
Other ways to do it
On a Mac you don't need any extra tool. Open one PDF in Preview and drag the second PDF's icon from the Finder into the sidebar. Preview saves changes automatically, so Apple's own guide suggests choosing File > Duplicate first if you want to keep the original untouched.
On a shared computer at a cyber café or office, an in-browser tool has one real advantage: your certificates are not sent to a server. Still, delete the downloaded files from the Downloads folder before you leave.
Questions people ask
Does merging reduce the quality of my certificates?
No. The pages are copied as they are rather than re-rendered, so a merged marksheet looks exactly like the original and its text stays selectable.
How many PDFs can I combine at once?
Up to 50 files, each up to 100 MB, with 200 MB in total. For a typical application that is far more than you need.
Can I merge photos and PDFs together?
Not directly. Convert the photos to a PDF first, then merge that PDF with the others.
Should I put everything into one PDF even if the form has separate boxes?
No. If the portal has one box for the photo ID and another for marksheets, upload separate files. A merged file in the wrong box is a common reason for an application to be sent back.