BASALT · JOURNAL
How to reduce PDF size without making text blurry
A smaller PDF is useful only if the recipient can still read it. The safest compression workflow identifies what makes the file large, changes that component, and checks text and images at the size people will actually use.
Find the source of the size
Scanned pages, oversized images, embedded fonts, duplicate objects, and attachments can all dominate a file. A text-heavy document may not shrink much from image compression. Remove unnecessary attachments and pages before changing image quality.
Compress selectively
Downsample photographs more aggressively than small text scans. Preserve monochrome line art and OCR clarity. Avoid repeatedly recompressing an already compressed image. Keep a source copy so you can compare readability and restore quality if needed.
Verify the result
Compare file size, page count, text search, print output, and representative images at 100% zoom. Check that signatures, barcodes, and redaction marks remain legible. Review metadata and attachments because compression does not remove sensitive content automatically.
Frequently asked questions
Why is a scanned PDF still huge after compression?
It may contain high-resolution color images, duplicate layers, or embedded source files. Inspect the document components instead of lowering quality blindly.
Does OCR increase file size?
It can add a text layer, but the searchability may be worth the cost. Optimize the underlying scans first.
Is “smallest file size” the right setting?
Not for legal, financial, or medical documents when it makes numbers or marks unreadable.
Doing it in Basalt
Basalt compresses PDFs locally and lets you review readability, searchable text, and document structure before sharing the smaller file. Download Basalt.
Redaction that proves itself
Basalt destroys the content you mark, then re-opens the file it wrote and proves the content is gone before it saves anything. Your documents never leave your Mac.