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It's the night before a deadline, you've got a 600MB screen recording, and the submission box rejects it. You search the limit, find a reassuring "5GB", and have no idea why your much smaller file won't go.
Here's the thing almost every help page leaves out: the figure the platform vendor publishes and the figure your campus enforces are two different numbers, and the second one is the one that matters.
There Are Two Limits, Not One
Every major learning management system has this split:
- The platform ceiling. The absolute maximum the software will ever accept. Set by the vendor, identical everywhere, and usually generous.
- Your institution's quota. A per-course or per-user storage allowance that your university's IT department configures. Far smaller, wildly inconsistent between schools, and the thing that actually blocks your submission.
When a classmate at another university tells you they uploaded a 1GB file fine, they aren't wrong — their campus is just configured differently from yours.
Canvas
Instructure, the company behind Canvas, documents a hard ceiling: Canvas does not support uploads larger than 5GB, per its own Files documentation. Instructure also states that this upload limit is fixed and cannot be modified, so your school can't raise it even if it wants to.
Your course quota is a separate matter entirely, and the published figures from US institutions show how much it varies:
| Institution | Documented course quota |
|---|---|
| Florida State University | 500 MB |
| Yale University | 1.5 GB |
| University of Illinois Chicago | 2 GB |
| Canvas Free-for-Teacher accounts | 100 MB |
That's a 20× spread between a free teacher account and a university course, and none of those numbers is the 5GB you'll find if you search "Canvas file size limit".
The useful exception
Files you submit to an assignment are generally not counted against your personal user quota in Canvas — only files you upload to your own Files area or a course Files area are. This is why you can sometimes submit a large assignment successfully but fail to upload that same file to your personal files. If you're hitting a quota wall, check which of the two you're actually doing.
Blackboard
Blackboard's default is documented at 2560MB — 2.5GB — and Blackboard's own file size documentation notes that its mobile apps cap at 250MB for both Original and Ultra courses. That mobile cap catches a lot of people out, because submitting from your phone can fail on a file that would upload fine from a laptop.
Institutional limits diverge even further than Canvas:
| Institution | Documented per-file limit |
|---|---|
| UMBC | 75 MB |
| Univ. of St. Augustine | 100 MB |
| Blackboard mobile apps | 250 MB |
| Blackboard default | 2,560 MB (2.5 GB) |
UMBC's figure is worth noting because its documentation explains the reasoning: the per-file limit exists specifically to protect a shared course quota, and it applies to instructors and students alike. That's the pattern across most campuses — a small per-file cap defending a modest course total.
Google Classroom
Classroom works differently, and it's the one case where the limit usually isn't the problem. Attachments live in Google Drive rather than inside Classroom, so your Drive storage quota is the real constraint. Google's assignment documentation notes you can attach up to 20 files to a single assignment.
Two practical consequences. First, if your personal Google account is out of space, Classroom submissions can fail for reasons that have nothing to do with Classroom — see our guide on what to do when Google Drive storage is full. Second, because the file stays in your Drive, revoking access later removes your instructor's ability to open it. Don't tidy up your Drive before a grade is posted.
How to Find Your School's Actual Limit
Thirty seconds of searching beats guessing:
- Search your university's name plus "Canvas file size limit" or "Blackboard upload limit". Almost every US institution publishes this in its IT knowledge base — every figure in the tables above came from one.
- If you're an instructor, open the course Files area. Canvas displays the quota and how much is used.
- Still unclear? Ask the campus help desk before the deadline, not after.
Treat any number you find on a general blog — this one included — as a starting point, not an answer. Only your own institution's documentation is authoritative for your account.
Video Assignments Are the Real Problem
Nearly every "my file is too large" situation in a US course comes down to video. A few minutes of screen recording at 1080p, or a phone clip shot in 4K, clears 500MB without effort — and 500MB is at or above the entire course quota at plenty of schools.
Before you fight the upload, try shrinking the file. Recording at 1080p instead of 4K typically cuts size by around three quarters. Exporting at 30fps rather than 60 roughly halves it again. For a screen recording of slides or code, those settings cost you nothing you'd actually notice.
If it's still too large, your instructor may well prefer a link. Video assignments are commonly submitted as links precisely because LMS quotas can't absorb them — but confirm before you assume.
What to Do When It Won't Submit
In the order worth trying:
1. Compress it. PDFs built from scanned pages or image-heavy slide decks often shrink by half or more with no visible loss. This solves most document cases outright.
2. Re-export video at lower settings. 1080p, 30fps. See above.
3. Submit from a laptop, not your phone. Specifically relevant on Blackboard, where the mobile apps cap at 250MB independently of whatever your campus allows.
4. Split it. If the work genuinely divides — a report plus an appendix — submit as separate files. Don't split a single video into parts; nobody wants to grade that.
5. Submit a link. With your instructor's agreement, upload the file elsewhere and put the link in the submission comment or text entry box. Your campus Google Drive or OneDrive is the most defensible choice, because it's institutional and won't expire mid-grading.
When you just need it to arrive
For a one-off handoff — getting a recording to a group partner, sending a file to an instructor who asked for it by email — Realtime Sender takes files up to 30GB free with no account, and gives you a short code to paste into a message.
One caveat worth being straight about: transfers here are temporary by design and delete after download or when the code expires. That's the wrong tool for a graded submission an instructor may open days later. For anything that needs to stay available, use your school's cloud storage.
Frequently Asked Questions
What is the file size limit in Canvas?
Instructure documents a hard ceiling of 5GB for Canvas file uploads, and that ceiling cannot be raised by your school. But your course has a separate storage quota set by your institution, and that is usually what stops you. Published course quotas range from 100MB on free teacher accounts to 2GB at some universities.
Why can't I upload a 400MB file if Canvas allows 5GB?
Because two different limits apply. The 5GB figure is the maximum single file Canvas will accept anywhere. Separately, your course has a storage quota set by your school, often 500MB to 2GB for the entire course. If the course is near its quota, a 400MB file will be refused even though it is well under 5GB.
Do assignment submissions count against my Canvas quota?
Generally no. Files you submit to an assignment are not counted toward your personal user quota in Canvas. Files you upload to your own Files area or to a course Files area do count. This is why you can sometimes submit a large assignment but not upload the same file to your personal files.
What is the Blackboard file size limit?
Blackboard's default maximum upload is documented at 2560MB, which is 2.5GB, and its mobile apps cap at 250MB. In practice your institution sets a much lower limit. Published campus limits include 75MB, 100MB, 250MB and 256MB, so the only reliable number is the one your own school documents.
How do I submit an assignment that is too large?
First compress it, since PDFs and slide decks often shrink dramatically. If it is still too big, check whether your instructor accepts a link instead of a file, which is common for video assignments. Upload the file to a transfer service or your school's cloud storage and submit the link in a comment or text entry box. Always confirm with your instructor first.
How do I check my own school's Canvas limit?
Search your university IT knowledge base for Canvas file size or storage quota. Nearly every US institution publishes its own figure, and those numbers differ widely between campuses. Your instructor can also see the course quota in the course Files area.
Platform limits and institutional quotas change. Figures here were checked against the vendor and university documentation linked above in October 2026; your campus is always the authority for your own account. Content from those sources has been summarised and rephrased rather than reproduced.