Why Assignment PDFs Are So Large
Students most often create large PDFs by photographing handwritten work on a phone and converting the photos to PDF. A single phone photo is 3-8MB. A 5-page assignment becomes a 15-40MB PDF before any compression. Some scanning apps also default to very high resolution. The result is a file far larger than needed for the teacher to read it on a screen.
How to Compress a PDF for Classroom Upload
Open the ToolMint Compress PDF page on your phone or computer. Tap or click Upload and select your assignment PDF. Choose Medium or High compression — for scanned handwriting, High compression is fine because the original resolution is much higher than the screen needs. Download the compressed PDF and re-upload to Google Classroom.
How Small Should a Classroom PDF Be?
For most school submissions, under 5MB is ideal and under 2MB is even better. A compressed 5-page scanned assignment should be well under 1MB at High compression, with handwriting remaining completely readable. If you are submitting something with printed text rather than handwriting — such as a typed essay exported as PDF — the file is already small and compression may not be needed.
Reducing Size Before Creating the PDF
If you regularly submit phone-captured assignments, reduce image size before converting to PDF. Most scanning apps have a quality or resolution setting. Setting it to Medium rather than High reduces the source image size by 50-70% before compression even runs. Apps like Adobe Scan, Microsoft Lens, and CamScanner all have quality settings worth checking.
Other File Issues in Google Classroom
Google Classroom accepts PDF, DOCX, PPTX, and image files. If a teacher specifies PDF format and your submission is too large, compression is the fix. If the classroom shows an error that is not about file size, check that the file is not password protected — use the Unlock PDF tool to remove any password before uploading.