Getting a PDF under an upload size limit

Getting a PDF under an upload size limit

Government and institutional portals impose file size limits, and scanned documents routinely blow past them. The good news is that oversized scans are almost always oversized for one avoidable reason.

Why your scan is enormous

A scanned PDF is not text. It is a sequence of photographs of paper.

Scan a two-page document in full colour at maximum resolution and you can easily produce several megabytes per page. The same document in greyscale at 200–300 dpi may be a fraction of that, and for reading purposes looks identical.

Colour is the bigger culprit of the two. Most documents contain black text on white paper, and storing that in full colour is spending file size on nothing.

Fix 1 — rescan properly (best result)

If you still have the paper, this beats every compression tool.

Settings that matter:

On a phone, use the built-in document scan mode rather than the camera. Most phones have one — in the Notes or Files app, or in the camera itself. It detects the page edges, corrects the perspective, converts to greyscale, and outputs a proper PDF. Raw camera photos are usually both larger and harder to read.

Fix 2 — compress what you have

Most PDF applications have a Reduce File Size or Optimize command. Choose a setting intended for screen viewing rather than printing.

Before compressing, delete what does not need to be there: blank pages, duplicate scans, the cover sheet, pages the portal did not ask for. Removing three pages beats compressing five.

A caution about online compressors. They are convenient, and using one means uploading your document to a server you know nothing about, in a jurisdiction you did not choose, often with unclear retention. For a document containing your passport number or financial details, that is a real trade-off — see Where your documents actually live when you upload them. Prefer a tool that runs locally.

Fix 3 — split it

If the limit is per file rather than per submission, split the document and upload the parts.

Name them so a human can follow: passport-pages-1-2.pdf, passport-pages-3-4.pdf — not part1.pdf. Somebody has to read these, and a clear name is the difference between a smooth review and a request for clarification.

Check first whether the portal allows multiple files for one requirement. Some do not.

The rule that matters most

Legibility first, size second.

An upload that fits but cannot be read gets rejected later by a person, and that rejection costs weeks rather than the ten minutes you saved. Before submitting, open the compressed file at full size and confirm you can clearly read:

• every digit of every number
• names, including accents and diacritics
• dates
• signatures
• stamps and seals
• any handwritten annotation

If any of those are mushy, go back and compress less.

When the portal still refuses

Size is not always the actual problem, and the error message is rarely specific. Check:

• Page count limits — some portals cap pages as well as megabytes
• File type — some accept only PDF, some only specific image formats
• Filename — spaces, accents, apostrophes and very long names break some upload widgets
• A different browser — some upload components fail silently in one browser and work in another
• The total submission size, not just the individual file
• Session timeouts — a long form session can expire mid-upload and report a vague failure

Assembling a submission

For an application with several required documents:

1. Read the requirement list first and produce exactly the files it names.
2. One document per file, unless told otherwise.
3. Name files descriptively — smith-jane-notice-of-assessment-2025.pdf.
4. Check each one opens and is legible before uploading anything.
5. Keep the originals at full quality — see How long to keep tax records and documents in Canada.
6. Record what you submitted and when, with a screenshot of the confirmation.

How my-id.ca helps

Uploading the same documents to the fifth portal this month is largely a filing problem, and my-id.ca is a filing tool: your documents live in one encrypted Canadian vault, searchable by their contents, reachable from any device — so preparing a submission does not begin with hunting through folders and email attachments.

Documents you fill in my-id.ca are generated as PDFs rather than scanned, which means they are text-based and small to begin with. And keeping the full-quality original alongside the compressed submission copy is straightforward when both live in the same place — see Storage: what counts, and how to free space.

Next steps

• Filling government PDFs on a phone
• How to fill a form from a photo
• Where your documents actually live when you upload them
• How long to keep tax records and documents in Canada

Important: this is general information, not legal advice

This article is general information about working with documents — it is not legal, immigration, technical, or professional advice, and my-id.ca does not provide legal or professional consultation. my-id.ca is not a government agency, law firm, lawyer, or licensed advisor, and is not affiliated with or endorsed by Adobe, Apple, Google, Microsoft, IRCC, or any government body.

Portal requirements — size limits, accepted formats, page counts — differ by agency and change over time. Always confirm the current requirements on the portal itself and on the issuing agency's official site (canada.ca and ontario.ca) before submitting. For advice about your individual circumstances, consult a qualified professional or a government-funded settlement agency. If anything in this guide differs from an official source, the official source is correct.