Scanned documents are deceptively large — a single colour scan can be several megabytes, far over the limit most exam, bank and visa portals set. Here's how to compress a PDF below the size you need while keeping the text and stamps clearly legible.

Why scanned PDFs are so large

A PDF made from photos or scans is essentially a stack of images, and colour images at high resolution are heavy. That's why a three-page scan can be 5–10 MB. Compressing works by re-encoding those page images at a lower (but still readable) quality, which can cut the size by 70–90%.

Compress to a specific target

The easiest way is a target page. Pick the limit your portal sets — 200 KB is the most common, with 100 KB, 500 KB, 1 MB and 2 MB also available — drop in your file, and download. The tool finds the highest quality that fits under your target. For a general squeeze, use Compress PDF.

If it's still too big

A few extra moves help on stubborn files:

  • Scan in greyscale or black-and-white where colour isn't required — it compresses far smaller.
  • Split the PDF or delete blank pages to remove weight before compressing.
  • If the file is a mix of odd page sizes, resize it to A4 first for consistency.

Keep it private

Because the whole process runs in your browser, your documents are never uploaded — which is exactly what you want for bank statements, certificates and ID proofs. Always confirm the exact size limit and format in your portal's official instructions before uploading.