PDF Compressor
Select a PDF from your device to re-save it with a more efficient internal structure. This runs entirely in your browser — your file is never uploaded to a server.
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PDF compressor
How It Works
Your PDF is reloaded and re-saved in your browser using pdf-lib with object-stream compression enabled, which can reduce redundant internal structure in the file. This is a genuine but limited form of compression — it doesn't re-encode embedded images the way a dedicated desktop tool would.
MyDelsu is an independent student platform and is not affiliated with DELSU administration. This tool is provided for guidance only — always verify results against your official transcript, result slip, or academic regulations.
This tool runs entirely in your browser — your file is selected locally on your device and is never uploaded to a server. Nothing leaves your device at any point.
Compression results vary by file — some PDFs (especially image-heavy ones) may not shrink much with browser-based compression. We never promise a specific ratio.
You select the file locally from your device (this is a local file selection, not a server upload).
Frequently Asked Questions
Is my file uploaded anywhere?+
No — everything happens locally in your browser. Your PDF is never sent to a server.
How much smaller will my file get?+
It depends entirely on the PDF. Files with redundant internal objects can shrink noticeably; image-heavy PDFs often shrink little or not at all, since this tool doesn't re-encode images. We show you the real before/after size so you can judge for yourself.
Why didn't my file get any smaller?+
Browser-based compression works on the PDF's internal object structure, not on re-compressing embedded images or fonts. Some PDFs are already efficiently structured and won't shrink further with this method.
Is this the same as a desktop PDF compressor?+
No — desktop tools can re-encode images and fonts for much larger savings. This tool trades some compression power for running entirely on your device with no upload.