Preparing PDFs for uni-assist: check file size and legibility

My assist requirements at a glance

The upload figures are in the uni-assist FAQ “Online bewerben” (applying online). On 13 October 2026, the FAQ stated that you can upload PDF documents only and that each individual file may be at most 10 MB in size. At this point, the FAQ does not state a limit on page count, total size of all documents or number of files.

“PDF only” refers to the actual file format, not the extension. Renaming a photo, a Word document or a ZIP archive to “.pdf” does not make it a PDF. Convert photos or scans in JPG or PNG format into a genuine PDF with Images to PDF. Export other files as PDF from the program in which they were created.

The FAQ leaves open how many bytes are meant by 10 MB. Counted decimally, that is 10,000,000 bytes; counted in binary (10 MiB), it is 10,485,760 bytes. Where exactly the limit lies in the portal is not publicly described. If you plan for at most 10,000,000 bytes, you stay within the stated limit under both readings.

These technical requirements are separate from your list of documents. Which documents you need to submit depends on the requirements for the country where you obtained your qualification. On top of that come any additional documents your university or degree program requires. You'll find the relevant official uni-assist pages in the source overview on this page.

Scan certificates completely and legibly

uni-assist requires complete and clearly legible scans of your official documents. According to the “Dokumente hochladen” page, a certificate is official if it meets one of these conditions: it bears both the signature and the stamp of the issuing institution, it contains a note that it was generated automatically, or it has a verification code. For the first condition, a signature without a stamp is therefore not sufficient. Additional conditions may apply for certain countries and in individual cases. These features are what make your document verifiable, so they take priority over any bytes you could save.

The page does not prescribe a fixed resolution such as 300 dpi. What matters is the result: small text, grades, stamp edges and codes must be clearly recognizable in the saved PDF. Reduce scanned PDFs explains how to choose suitable resolution and color mode settings when scanning.

• All pages are included, including back sides if there is something on them.
• No margin is cut off, and stamps, seals and signatures are fully visible.
• When you zoom in, you can read numbers and small text without guessing.
• QR and verification codes are sharp and complete.
• Nothing has been covered, retouched or removed just to make the file smaller.

Original language and translation

According to the uni-assist page Übersetzungen (translations), you upload certificates and transcripts in the original language and additionally as a translation into German or English. Documents officially issued in German or English generally do not need a translation, although there are exceptions for some countries. Recognized translations are those made by sworn or court-authorized translators or by authorized offices of the issuing school or university. Ordinary translation agencies without this authorization are not sufficient.

Make sure stamps, annotations and verification features stay fully visible on both the original and the translation. The public uni-assist pages we checked don't specify in general whether the original and the translation belong in one PDF or should be uploaded as separate files. Follow the current instructions in My assist and from your university.

Reduce the file and check the limit

If a scan is larger than allowed, you can reduce it in your browser with PDF to target size. The input file may be up to 50 MiB. Here is how it works:

1. Keep the original file as a separate copy. The tool does not overwrite it, so it always creates a new file.
2. Click “Choose PDF” and select your scan.
3. Choose the method. The lossless method optimizes the PDF's structure and data streams without changing image quality. “Balanced” and “Smaller file” re-encode suitable images as JPEG. The stronger the reduction, the more likely it is that fine details are lost, which is especially noticeable with stamps and small text.
4. Set the target size to 10 MB. The tool uses 10,000,000 bytes for this and aims for a file that does not exceed this value.
5. Click “Reduce PDF to a target size” and download the result. If no smaller valid result is produced, you receive an unchanged copy of the original.
6. Open the saved file and go through each page using the list from the previous section.

A reached target only means that the saved file is at most 10,000,000 bytes in size. This result does not tell you whether My assist will accept the file or whether its content is sufficient. There is no guarantee of a particular reduction; how much is possible depends on the PDF's content. If the file remains too large, you can find the causes in PDF won't get smaller.

The compressor rejects digitally signed or certified PDFs as well as encrypted files. PDFs with signatures and forms explains what you can do in that case and why a scanned signature is not a digital signature.

Exact bytes instead of a rounded display

A rounded display such as “10 MB” does not reveal whether the size was counted decimally or in binary. In the upload limit calculator, select your PDF. The calculator reads the exact file size in bytes and compares it with the limit you enter. Enter 10 MB to check against 10,000,000 bytes, or 10 MiB for the binary reading. The calculator does not change the file and is not connected to My assist.

Merge or split?

The public uni-assist pages we checked don't specify in general whether you should bundle your documents into one PDF or spread them across several files. Whether you split a document or combine pages depends on the current instructions in My assist and from your university. If they allow it, use Split PDF to spread a document across several files; how large the individual parts turn out depends on the content, because shared components can end up in several parts. With Merge PDF, you combine pages into one file, which usually makes it larger. Both tools load ordinary PDFs of up to 50 MiB per file and no more than 250 pages, and when merging, no more than 100 MiB of input in total; they reject PDFs with digital signatures, interactive forms, embedded attachments or layers. If your document is larger or longer, it's better to create the parts separately when scanning or in the original program, or to use another suitable PDF program and make sure signatures, stamps and codes are preserved. Don't leave out any required page just to fit a file under the limit, and check the size of the saved files again after each step.

Upload in “Meine Dokumente” and update later

Uploads go into the “Meine Dokumente” (My Documents) section in My assist. The public uni-assist pages we checked don't describe in detail exactly how to categorize a document there. When uploading, follow the current notes in My assist and your university's instructions.

Important for later corrections: according to the FAQ, you can no longer delete a file that has already been processed. However, you can upload a newer version to update the document. Before each upload, check whether the file is really complete instead of relying on replacing it later.

1. Check your university's list to see which document is missing or should be replaced.
2. Check the new file for completeness, legibility and size.
3. Give it a unique name with a date, for example “Bachelorzeugnis_Uebersetzung_2026-10-13.pdf”, so you can distinguish it from older versions.
4. Upload them in My assist under “Meine Dokumente” (My Documents) and follow the current notes in the portal.
5. Afterwards, check in My assist which file is displayed there.

Keep the original and earlier versions on your device until your application is complete. This guide helps you with the technical preparation of the files. uni-assist and your university decide whether your documents are complete and whether you are admitted. For job applications to employers with a cover letter and CV, there is a separate guide: Reduce application PDF.

Upload fails even though the file is small enough

Format and size are not the only possible causes. For example, the uni-assist FAQ describes the message “Bad Request” and names a network or firewall problem as a possible cause. The message may therefore point to such a problem, but it does not mean your PDF is too large. Check the format and exact size once, then follow the error message instead of compressing the file again and again. Each additional lossy compression can make small text, stamps and codes harder to read without fixing the actual error.

1. Note the exact wording of the error message, the date and time, and the file name and exact size in bytes.
2. Check once whether the file is a genuine PDF and at most 10,000,000 bytes in size. If both are fine, don't make any further changes to size or quality.
3. Do not turn off any security settings on your device or network. Instead, try another trusted device or network that you are allowed to use.
4. If the error persists, contact uni-assist through the contact channels listed on the uni-assist website and include your notes.
5. After each new attempt, check in “Meine Dokumente” whether a file has arrived and which file it is.

Save each modified version under its own name with a date. That way, if questions come up, you know exactly which file you uploaded and can go back to the more legible version at any time.