How to compress without sacrificing the quality of the original file.

Learn how to compress PDFs to size limits like 5 MB, 1 MB, or 300 KB using the Smallpdf Compress PDF, plus proven tactics for strict upload rules.

Need to compress a PDF to meet a strict upload limit? While you can't type in an exact target size, you can get very close quickly with the right compression settings and a few practical workarounds.

Oversized PDFs tend to fail at the worst moment: a form rejects your upload, an email won't send, or a portal caps attachments at 1 MB and your PDF comes in just over the limit.

In this guide, we'll show you how to compress a PDF to a chosen size using Smallpdf, plus what to do when standard compression isn't enough for tight limits like 500 KB or 300 KB.

Use this table to choose the right approach first, then refine if needed.

Note: Benchmark based on a 50 MB file; larger inputs yield larger outputs.

When people want to compress a PDF to a specific size, they usually mean:

Most online tools, including Fynepdf, don't let you enter an exact size like "make it 500 KB." PDF content varies too much. Instead, the tools optimize your file and show the final size, so you can adjust with extra steps if you're still over the limit.

Fynepdf's Compress PDF is the fastest way to shrink a PDF while keeping it readable.

Open Compress PDF in your browser..

Drag and drop your file into the upload area, or click "Choose Files."

You can upload from:

You'll see two options:

Download your compressed PDF, then check the size:

If you're still above the limit, use the tactics in the next section.