Open the downloaded copy
Do not judge the preview or the original. Open the exact file created by the compressor in a normal PDF viewer. Confirm that it loads without a repair warning and that the viewer reports the expected filename and page total.
Guide
Check a compressed PDF before submitting it.
File size is only the first pass condition. A submission-ready PDF must also preserve every piece of information the recipient needs.
Inspect every page at useful zoom
Move from the first page to the last and check page order, orientation, margins, and cropping. Zoom into the smallest important text, faint handwriting, stamps, signatures, diagrams, and identification numbers rather than assuming the cover page represents the rest.
Test features you expect to keep
Try selecting text, clicking links, using bookmarks, typing into form fields, and searching for a known phrase when those behaviors matter. Strong page-image compression can remove them even when the document still looks correct.
Check machine-readable details
A barcode, QR code, or fine document number can fail before surrounding text looks obviously blurry. Scan codes from the compressed file when possible. If the receiving organization relies on automated reading, prefer a gentler result.
Verify privacy and redaction
Compression is not redaction. Hidden layers, metadata, annotations, or content outside a crop may require a dedicated redaction workflow. Review what is visible, and use an appropriate redaction tool before compression when sensitive information must be irreversibly removed.
Record the final size and source
Confirm that the finished file is below the stated target, keep the original separately, and upload the verified download. A clear filename such as application-document-under-1mb.pdf can help prevent accidentally selecting the uncompressed source.