Compress PDF to 150 KB

Get a PDF under 150 KB for an application portal. Type the size, check page 1 in the preview, and download. Free, no sign-up, and nothing is uploaded.

Before you start

150 KB falls between the 100 KB and 200 KB limits that many portals use, and some set it for each document. Shared evenly, it gives about 75 KB a page to a 2-page document and 30 KB a page to a 5-page one.

The PDF tool below opens with 150 KB typed in. It keeps the pages as sharp as it can and lowers them only as far as it must. If your PDF is already under 150 KB, the tool tells you, and you keep your original.

Tips

Look at the three ready-made sizes (Small, Medium and Large) before you type. Their real sizes show on the cards, and one of them may already be under 150 KB.

Scanning the pages? 150 to 200 DPI is enough. The tool saves pages at no more than 150 DPI, so a 600 DPI scan only gives you a bigger file to start with, not a sharper result.

For pages of printed text, tick "Black & white". Keep colour for photos, stamps and coloured signatures.

A worked example: 3 scanned pages in 150 KB

Take a colour scan of 3 pages. Shared evenly, 150 KB gives each page about 50,000 bytes.

SafeResize saves each page as a picture. It starts at 150 DPI, where an A4 page is about 1240 × 1754 pixels, and lowers the JPG quality until the file fits. If even a low quality is too big, it steps down: 120 DPI, then 96 (about 794 × 1123 pixels for A4), 72 (about 595 × 842), 56 and 45. It stops at the first step that fits.

The result page shows the DPI it used. Under 90 DPI, it asks you to zoom in on the small text. Ticking "Black & white" often lets the same pages fit at a higher DPI, because a grey page needs less space than a colour one.

Questions and answers

What does 150 KB mean in bytes?

It is 150,000 bytes if a website counts 1,000 bytes to a KB, and 153,600 bytes if it counts 1,024. SafeResize keeps the PDF under 150,000 bytes, so it passes both.

Why does the preview show only page 1?

Page 1 is shown exactly as it was saved, so you can judge the sharpness. The other pages are made the same way. Open the downloaded file to look at every page.

Will the pages keep their size and order?

Yes. Every page keeps its paper size and its place in the document. Only the picture on each page gets lighter.