Reduce PDF size without quality loss
Most compressors trade visible quality for size — the result is a file that uploads but looks washed-out, especially on diagrams and screenshots.
Why this works
PDFRun's Lossless mode strips embedded fonts you don't need, deduplicates repeated images, removes unused objects and re-encodes with Flate compression. Pages look pixel-identical to the original, but the file is meaningfully smaller.
How it works
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1Open the toolClick the orange button above and select the "Lossless" preset.
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2Upload your PDFDrop the file in. Works for files up to 100 MB on the free tier.
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3Run lossless compressionImage data is preserved exactly; only metadata, fonts and structure are optimised.
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4Compare and downloadUse the side-by-side preview to confirm visual parity, then save.
Who this is for
Real-world uses
Designers
Send portfolio PDFs without dulling colours or softening type.
Engineers
Share schematics and CAD exports where every line must stay crisp.
Academic authors
Submit papers where figures and equations must remain print-ready.
FAQ
Common questions
How much does lossless save?
Typically 10–35%. Larger savings usually require some image re-encoding.
Will fonts still render correctly?
Yes — only unused glyphs are stripped, never glyphs that appear in your document.