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Compress PDF to Under 500KB – For Strict Upload Limits

A free tool that automatically compresses a PDF to under 500KB. It’s made for forms and application systems with strict limits. Photos and scanned images are compressed first, and text is kept readable. Your file is processed in your browser and never uploaded.

Your files are processed in your browser and are never uploaded to a server.

How to compress a PDF to under 500KB

  1. 1Tap “Select PDF file”, or drag and drop a PDF.
  2. 2Compression to under 500KB starts automatically. Longer documents take a little more time.
  3. 3Check the size before and after, and the preview.
  4. 4Tap “Download compressed PDF” to save it.

Supported files and limits

Supported files
One PDF file (.pdf)
You get
A compressed PDF
File size
Up to 100MB per file
Good to know
  • Only the images inside the PDF are compressed at first, so text stays as it is. Pages are turned into images only if the target size can't be reached otherwise (text can then no longer be selected or searched).
  • Password-protected or edit-restricted PDFs can't be processed. Remove the password first with Unlock PDF.

When you need a PDF under 500KB

500KB is one of the stricter limits. Short documents usually fit, but photo-heavy or long PDFs need more care.

ID copies

Copies of a My Number card, driver’s license or residence card often need to be small. One- or two-page documents like these usually fit in 500KB.

Online forms with strict limits

Some school, municipal and company forms accept only very small files.

Limits vary by site and organization. Always check the instructions where you’re submitting.

How this tool gets your PDF under 500KB

The tool first compresses only the photos and scanned images in your PDF, keeping text and layout as they are wherever possible. If that gets it under 500KB, text can still be selected and copied.

Only if that isn’t enough are pages turned into images to shrink further, and never below a quality where text stays readable. If 500KB can’t be reached while keeping text readable, the tool tells you, and you can still download the smallest file it made.

If your PDF won’t go under 500KB

PDFs with many pages or photos may not fit. Try these:

  • Delete pages you don’t need (blank or unrequired pages) before compressing
  • Split the PDF by document and check whether you can submit several files
  • If color isn’t needed, convert to grayscale before compressing
  • If a larger size is allowed, compress to under 1MB instead

We count 500KB the smaller way

Sizes can be counted two ways: 1MB as 1,000,000 bytes or as 1,048,576 bytes. This tool uses the smaller definition (1KB = 1,000 bytes, 1MB = 1,000,000 bytes), so your file stays under the limit either way.

Your documents stay on your device

Your PDF isn’t uploaded to a server; it’s processed in your browser. Documents with personal information, such as résumés and ID copies, are compressed without leaving your device. The data is discarded when you close the page.

Works with documents scanned on your phone

Open this page in your iPhone or Android browser and select a PDF from the Files app or Google Drive. No app is needed. Long PDFs are faster on a computer.

Check before you submit

  • Small text such as names and dates is readable in the preview
  • Photos and seals aren’t blurred beyond recognition
  • Pages are in the right order and orientation (fix them with Rotate PDF or Reorder PDF Pages)
  • Keep the original file too (text may not be selectable after compression)

Frequently asked questions

Q. Is it free?

A. Yes. It’s free with no usage limits, and no watermark is added to your PDF.

Q. Will my PDF always get under 500KB?

A. Most PDFs of a few pages fit, but PDFs with many pages or photos may not reach 500KB while keeping text readable. The tool tells you when that happens.

Q. What should I do if it doesn’t fit?

A. Delete unneeded pages, split the PDF, or convert it to grayscale, then compress again.

Q. How is 500KB counted?

A. As 500,000 bytes, the smaller of the two common definitions, so it stays under the limit either way.

Q. Will compression lower the quality?

A. Photos and images get lower quality, but text is kept as it is wherever possible and never made unreadable. Check the preview before downloading.

Q. Can I still select text afterwards?

A. Yes, if compressing images was enough. If pages had to be turned into images, text can no longer be selected, and the tool tells you.

Q. What if my PDF is already small enough?

A. The tool tells you it’s already under 500KB and can be submitted as it is.

Q. Is my PDF uploaded to a server?

A. No. Your PDF is processed in your browser and never uploaded. The data is discarded from memory when you close the page.

Q. Does it work on a smartphone?

A. Yes. It works in iPhone and Android browsers with no app to install.

Q. Do I need to sign up?

A. No. There’s no account and no email address required. Just open the page and use it.

Q. Can I compress a password-protected PDF?

A. No. Password-protected PDFs can’t be compressed. Remove the password first, then try again.

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