Compress PDF to 50 KB or less
Add your PDF, press Compress, and the tool makes it 50 KB or smaller, using the sharpest quality that fits. It runs on your device: no upload, no sign-up, no limit on how many files you do.
- Free, no sign-up
- Runs in your browser
- Nothing uploaded or kept
How to use it
Add your PDF
Drop it in the box, or choose it. You can merge, reorder or delete pages first.
Check the limit is 50 KB
The 50 KB button is already selected. Pick another size, or type your own, if your form wants something different.
Compress and download
See the result size and whether it fits, then download it.
Drop PDFs or pictures here
The tool is loading. Add as many files as you like, of any size your device can hold.
Your files stay in this page. Nothing is uploaded, and nothing needs an account.
What 50 KB means in bytes
50 KB is 51,200 bytes, counting 1 KB as 1,024 bytes, which is how file managers and most upload forms count. A few forms count 1 KB as 1,000 bytes; if yours is one of them and the file is rejected by a small margin, choose a slightly lower size (for example 45 KB).
Why people compress to 50 KB
A 50 KB limit shows up on online application forms that ask for a short scanned document, a certificate or a signed page.
How the tool gets there
Each page is redrawn as a picture and saved at the quality that lands just under 50 KB: the tool tries a few settings on sample pages, writes the whole file once and measures it against 51,200 bytes, and if it came out over (or well under) it adjusts in proportion and goes round again, up to four times. In our tests one dense A4 page of scanned text fit 50 KB but came out soft, and three such pages did not fit (the smallest was 69 KB). If your PDF is already under 50 KB, the tool says so and leaves it alone with its text intact; at a hard limit the text in the result can no longer be selected or searched, and the file you added is never changed.
If it cannot reach 50 KB
Keep the document to a few pages, and remove covers and blank pages first. The tool never claims a size it did not reach: it shows the smallest result it could make and says how far over it is.
Also searched for as: compress pdf to 50 kb, reduce pdf size to 50 kb, pdf under 50 kb.
Related PDF tools
- Compress PDFAdd your PDF, pick the largest size you can send (20 KB to 5 MB, or your own), and the tool finds the sharpest quality that fits.Open
- Merge PDFDrop two or more PDFs (or pictures) into the page, drag the pages into the order you want, and download one PDF.Open
- Delete pagesAdd your PDF, click the pages you do not want, press Delete, and download what is left.Open
- Reorder pagesAdd your PDF, drag the pages into the order you want (or use the arrows on a phone), and download.Open
Frequently asked questions
Will my PDF still be readable at 50 KB?
Usually, but it depends on the pages. The result screen says whether the text should read clearly, may look soft, or may be hard to read, so you can check before you send it. A page of small print squeezed into 50 KB will be softer than a page with large type.
Why does my PDF not get smaller than 50 KB?
Every page costs a few hundred bytes of structure plus its picture, so a PDF with many pages has a floor, and 50 KB may sit below it. In our tests that floor was about 23 KB for a dense scanned page. A PDF that is only text can already be smaller than its pages drawn as pictures; then the tool gives your original back and says so. Remove pages you do not need from the list, or choose a larger size, and compress again.
Are my files uploaded anywhere?
No. The tool runs in your browser: your files are read and written on your own device and nothing is sent to a server. You can check this yourself by opening your browser's network tab while you use it.
Is there a limit on file size, pages or number of files?
We set none: no cap on files, pages or megabytes, no daily limit and no sign-up. The only limit is your device's memory, and the tool warns you when the files you add come to more than about 400 MB.
What can this not do?
It works on pages: it reorders, turns, deletes, splits, merges and compresses them, and converts pictures and pages. It does not read the text in a scan (no OCR), edit the words inside a page, open password-protected PDFs, or convert to Word or Excel.
Does it add a watermark or anything else to my pages?
No watermark and nothing drawn on your pages. The only trace is the PDF's Producer field, which says the file was made by LetRelay free PDF tools.
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