Why Is My Compressed PDF Larger?

Sometimes a compressed PDF comes back barely smaller — or in rare cases slightly larger. This is expected behavior for certain files, not a bug, and understanding why points to the right fix.

The file was already optimized

PDFs exported from modern software are often already well compressed. Text compresses efficiently, so a text-heavy report or ebook may have almost nothing left to remove — savings of a few percent are normal here.

Re-encoding can add a little overhead

Rebuilding a PDF (restructuring objects, embedding processing metadata) can add a small amount of weight. On a file with no compressible content, that overhead can outweigh the savings, producing a slightly larger file. The report shows the honest numbers so you can keep the original instead.

What to try instead

If Balanced did little, the remaining options depend on the content:

• Try Maximum Compression — it recompresses images aggressively and is the best shot at further savings.
• Check for large embedded images: scanned pages at high resolution are the most common culprit.
• Split out only the pages you need — fewer pages means a smaller file regardless of compression.
• If quality already looks perfect and the file will not shrink, accept the original: not every PDF can get smaller without visible damage.