How to Compress a PDF

Click Choose PDF or drag and drop your file onto the upload area.
Select a compression level — Standard removes unused metadata; Aggressive re-renders pages at lower resolution.
Click Compress PDF and wait for processing to complete.
Download your compressed file and compare the original vs. new file size.

Standard vs. Aggressive Compression

Two compression modes are available depending on your needs:

Standard compression — Removes unused objects, duplicate streams, and metadata bloat. Preserves all content at original quality including selectable text. Best for PDFs that need to stay searchable or editable. Typical reduction: 5–30%.
Aggressive compression — Re-renders each page as a downsampled JPEG image and combines them into a new PDF. Achieves much higher reduction (50–80%) but removes selectable text and may reduce sharpness on text-heavy pages. Best for scanned documents, forms, and PDFs you only need to read and share.

Why Compress PDFs?

Email attachments: Most email services have a 10–25 MB attachment limit. Compressing large PDFs ensures they get through.
Web uploads: Many portals, HR systems, and submission forms cap file sizes at 5–10 MB.
Storage: Smaller PDFs save space on drives and cloud storage services.
Sharing: Compressed files are faster to upload, download, and share via messaging apps.
Bandwidth: Smaller PDFs load faster in PDF viewers and browsers.

What Affects PDF File Size?

PDFs grow large for several reasons:

Embedded images: High-resolution photos embedded at full quality are the most common culprit.
Embedded fonts: Full font sets embedded for compatibility can add hundreds of KB.
Metadata and history: Editing history, creator metadata, and revision information adds overhead.
Redundant objects: PDF editors sometimes leave unused objects and streams in the file.

Frequently Asked Questions

Is my PDF uploaded to a server?

No. Everything runs in your browser using JavaScript. Your PDF is read locally, processed in memory, and never transmitted to any server. Your document is completely private.

How much will my PDF shrink?

Standard mode typically reduces size by 5–30% by removing unused objects. Aggressive mode re-renders pages as images, achieving 50–80% reduction. Results vary greatly depending on the PDF content. Image-heavy PDFs compress the most.

Will compression affect quality?

Standard mode preserves all content at original quality. Aggressive mode reduces image resolution, so text-heavy pages may show slightly reduced sharpness when zoomed in. For most reading purposes, the quality difference is not noticeable.

My PDF barely got smaller — why?

Some PDFs are already well-optimized or contain content that doesn't compress well (e.g., already-compressed JPEG images, or minimal metadata). If standard compression barely helps, try aggressive mode. If the file is still large after aggressive compression, the content itself may be the limiting factor.

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