Compression · Knowledge
How to Reduce PDF Size
Email gateways and form uploads often reject multi‑MB PDFs. A local PDF compressor rasterizes or re-encodes pages so the download fits the limit — keep the original if you still need a text layer.
Quick take: Use the PDF Compressor with a quality slider for scans and image-heavy docs. Keep the master when selectable text or print fidelity matters.
Why PDFs get huge
Phone scans, embedded photos, and high-DPI page renders dominate size. Pure text PDFs are usually already compact.
What compression does
Format Convertly’s PDF Compressor re-encodes pages as JPEG-backed content for size. That can flatten selectable text — treat the result as a delivery copy.
Workflow tips
Start higher on the quality slider for contracts. Lower it for rough scans meant only for preview. Merge or split first if you only need a subset of pages.
Key points
- Image-heavy PDFs shrink the most.
- Compression may sacrifice selectable text.
- Always keep the original master PDF.
Open a compressor
Shrink files privately in your browser — pick a category, then a format tool when you know the extension.
Shrink large PDFs locally with a quality slider before email or upload.
Related compression guides
Related quality guides
Related concepts
FAQ
Will text stay selectable?
Often not after image-based compression. Keep the original if you need copy/paste or accessibility text.
Is the PDF compressor free?
Yes — it runs in your browser on Format Convertly with no signup.
Browse all compression guides, compressors, or quality guides.