What is the difference between Low, Medium, High, and Lossless?

Lossless reorganises the PDF's internal data without modifying images. No visual change, but typically a modest size reduction. Low keeps images at close to their original resolution, suitable when the output still needs to print at high quality. Medium targets standard screen resolution, the right choice for sharing by email and uploading to portals. High targets the smallest possible file. Image quality is reduced and visible under close inspection, but text and document structure are unchanged at every level.

Can I compress a password-protected PDF?

No. PDFHaul cannot process encrypted PDFs. If your file requires a password to open or has owner-level restrictions, remove the password protection first using a PDF editor, then upload the unlocked file.

Why did my PDF barely compress?

Your PDF is likely made up mostly of text and vector graphics rather than raster images. PDF text is stored as font instructions rather than pixels, so there is nothing to resample. If your file is text-heavy and already small, the Lossless option may still reduce it slightly by stripping redundant internal data structures.

Does compression change the text or fonts in my PDF?

No. Compression only targets raster images. Text is rendered from font outlines and is never resampled at any compression level. The text in your compressed file is visually identical to the original at any zoom level.

Does compression work on scanned PDFs?

Yes, and this is where it is most effective. A scanned PDF is entirely composed of raster images, one per page. These compress substantially. The text is still readable after compression; it is rendered at a lower pixel density appropriate for screen viewing rather than print.

Is it really free to compress PDFs?

Yes, completely free with no daily limits and no watermarks on the output. No subscription required.

What is the file size limit?

Each PDF can be up to 50MB on the free tier. PDFHaul supports all common PDF versions and formats including scanned documents and PDFs with embedded images.

Compress PDF Files Online

Reduce PDF file size without losing quality. Choose Low, Medium, or High compression to get the right balance for your document. No software to install, no account required, and no files stored after you're done.

Drop your PDF here

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Up to 50 MB

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How to Compress PDF

1
Upload your PDF
Click the upload area or drag and drop your PDF. Files up to 50MB are supported on the free tier.
2
Choose your compression level
Select Low, Medium, or High compression depending on how small you need the file. Medium offers the best balance of quality and size savings for most documents.
3
Download your compressed PDF
Click Compress PDF and download your optimised file in seconds. No watermarks, no signup required.

Why use PDFHaul
to compress PDFs?

Choose your compression level

Three modes: Low for minimal changes, Medium for the best size-to-quality balance, and High for the smallest possible output. You decide the trade-off.

Files deleted in 2 hours

Your documents are automatically purged from our servers within 2 hours. Not stored, not analysed, not sold.

No watermarks, ever

Your compressed PDF is clean. No branding, no watermarks, no trial version stamps on your documents.

Works on any device

Use PDFHaul on desktop, tablet, or mobile browser. No app install needed for the web version.

Who needs to
compress PDFs?

Oversized PDFs cause problems for anyone sharing files over email or uploading to web portals.

Email attachments

Many email providers cap attachment sizes at 10-25MB. Compressing PDFs before sending avoids bounce-backs and makes attachments load faster for recipients on mobile connections.

Uploading to portals

Government portals, legal filing systems, and client platforms often impose strict file size limits. Compressed PDFs slip through without manual workarounds or splitting the document.

Cloud storage and archiving

Reducing file sizes cuts storage costs and speeds up sync across devices. Compress a backlog of old PDFs and free up space without losing any document content.

Sharing large reports

Finance reports, audit packs, and research documents can run to dozens of megabytes. Compression makes them practical to share over email or via link without any visible quality compromise.

How PDF compression works

When PDFHaul compresses a PDF, it resamples the raster images embedded in the file using Ghostscript. A photograph embedded at 300 pixels per inch gets downsampled to a lower pixel density depending on the level you choose. At normal screen viewing distances the difference is imperceptible, but the file is substantially smaller.

Text in a PDF is not an image and is not affected. PDF text is stored as font definitions and character codes, already a compact format with no pixel data to remove. A contract or report that is mostly typed text will compress by a small percentage regardless of the level you choose. A scanned document where every page is a photograph can compress by 70% or more at High compression.

The four levels correspond to different image quality targets. Lossless reorganises the PDF's internal structure without touching images, appropriate when you need the smallest possible file with no visual changes. Low keeps images at close to print quality. Medium targets screen reading quality, which covers most email and portal use cases. High targets the smallest file size. Images are noticeably softer under close inspection but acceptable for archiving or bulk distribution.

Adobe Acrobat applies the same underlying approach in its PDF Optimiser, alongside optional steps like font subsetting. For most documents, image resampling accounts for the majority of file size reduction. The results PDFHaul produces at Medium and High compression are comparable to Acrobat's equivalent output intents for image-heavy PDFs.

Frequently asked questions

Everything you need to know about compressing PDFs

It depends on how much raster image content the PDF contains. A scanned document where every page is a photograph can shrink by 70% or more at High compression. A PDF built entirely from text and vector graphics may only reduce by 5-15% at any level. PDF text and vector paths are compact by design and are not resampled. The results screen shows the exact before and after sizes for your file.