The upload form says my PDF is too large
Every portal states its limit somewhere in small grey text, then rejects the whole file when you exceed it. The fix is not “compress harder” — it is knowing the number and working backwards from it.
Compress to Size — free and local
Takes your upload limit in KB or MB and finds the best quality that still fits under it.
Find the real limit first
Look for it near the upload control: “max 2 MB”, “文件大小不超过 500KB”, “attachments must be under 5 MB”. Government services, university application systems and job portals usually publish it, and it is usually smaller than people expect — 1 MB or 2 MB rather than 25 MB.
If the limit is not stated, assume 2 MB. That is the most common default, and a file comfortably under it passes almost anywhere. Aim for 70–80% of the stated limit: some portals re-process your file and add their own overhead.
Work backwards from the number
The exact-size compressor measures a few pages to learn how heavy your document is, then picks the resolution and JPEG quality that will land under your limit. Unlike preset compressors, it verifies the actual output size and steps down again if it overshot — so you are not guessing in a loop.
When the limit is genuinely unreachable for a long scan, it tells you the smallest honest result instead of silently handing over a blurry file that passes the upload and fails the reviewer. In that case, split out the pages that matter and compress only those.
Two other levers that work better than compression
Remove pages. A 40-page scan that needs to be 2 MB is a page-count problem; a 4-page extract of the pages the reviewer actually reads is a compression problem, and it solves easily.
Remove images. If the document is a text report with a few heavy photos, converting the photos to lower-resolution JPEGs outside the PDF and re-inserting them saves more than re-encoding the whole document.
Questions
What if my PDF still will not fit?
You get the smallest faithful version plus a clear message that the target was not reached. Split the document and compress only the pages that need submitting — that almost always fits.
Does it keep text selectable?
Reaching a hard limit means rebuilding pages as images, so no. The trade-off is unavoidable: text layers cost kilobytes, full-page images cost megabytes.
Is the file uploaded anywhere?
No. The compression runs in your browser tab. Nothing is transmitted, so there is no server copy and no retention policy to worry about.
Related
SlimPDF runs every tool in your browser. No file is ever uploaded, stored or shared.