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Byte budget · minimum size
Increase PDF file size
An unusual thing to want, until a submission portal tells you your document must be at least 100 KB and your neatly produced two-page PDF is 38 KB. This adds inert bytes inside the file structure until it reaches the size you name.
Result
How the padding works
A PDF is a collection of numbered objects with a cross-reference table pointing at them. Nothing in the specification requires every object to be reachable from the page tree, and readers simply ignore the ones that are not. The tool registers one extra stream object containing filler text, of exactly the length needed, and the document is written out again with that object included.
Your pages, fonts and images are copied across without modification, so the document opens, prints and reads exactly as it did before. If the arithmetic leaves it a few bytes short after the rewrite, the remainder is added as a trailing comment, which readers skip because the cross-reference table already told them where the document ends.
When this is the wrong answer
If the portal's minimum exists because it expects a scanned document and you are submitting a small text-only PDF, padding gets you past the validator but may still fail a human check. In that case, export at a higher resolution or add the pages you were asked for. Padding solves a byte count, not a content requirement.
Common questions
Will the padded PDF still open normally?
Yes. The document structure stays valid and the unreferenced object is skipped by every reader. Open the result before you submit it, as a matter of habit.
Can I make a PDF exactly 100 KB?
Very close. The tool measures the file after the rewrite and tops it up, landing within a few bytes above your target. It aims slightly over rather than under, because a minimum requirement is failed by being short, not by being long.
Does this work on a password-protected PDF?
Only if it opens without a password. Encrypted documents cannot be rewritten without the key, and this tool will report an error rather than guess.
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