How to use pdf24 compress PDF to 600 KB in 4 steps
- Choose the PDF. Tap Choose PDF files or drop the document on the box. Several files are fine; each one gets its own result.
- Keep the 600 KB target. Exact size is preselected with 600 KB as the limit. Type a slightly lower number if the portal is strict.
- Press Compress PDF. A lossless save is tried first; then pages are redrawn at lower resolution, step by step, until the file fits.
- Download and check. Save the -compressed.pdf copy and open it to confirm every page is still readable.
What fits in 600 KB with pdf24 compress PDF to 600 KB?
A 600 KB limit holds many pages of typed text, because text costs about 1 KB per page. Scanned pages are heavier: in our tests a readable scanned page needed 15 to 20 KB, so 600 KB fits about 33 scanned pages. Colour photos need the most room per page.
| Pages | Budget per page | Typed text | Scanned pages |
|---|---|---|---|
| 1 | 600 KB | Fits easily | Fits easily |
| 2 | 300 KB | Fits easily | Fits easily |
| 3 | 200 KB | Fits easily | Fits easily |
| 5 | 120 KB | Fits easily | Fits easily |
| 10 | 60 KB | Fits easily | Fits easily |
| 20 | 30 KB | Fits easily | Readable |
pdf24 compress PDF to 600 KB for scanned pages
Scans are pictures of paper, so every page is an image. Grayscale at about 150 DPI keeps text sharp at a fraction of the size of a 300 DPI colour scan.
pdf24 compress PDF to 600 KB for photo pages
Photo pages lose the most when squeezed hard. Keep one photo per page and crop away table tops or floors before you build the PDF.
pdf24 compress PDF to 600 KB for typed documents
Files exported from Word or a browser are mostly text and fonts. They often fit 600 KB after the lossless save alone, with text still selectable.
pdf24 compress PDF to 600 KB: how kilobytes are counted
The tool counts 1 KB as 1,024 bytes, the stricter way, so a result shown as 600 KB also passes portals that count 1,000 bytes per KB.
How small can pdf24 compress PDF to 600 KB go and stay readable?
Compression to 600 KB stops at the first setting that fits. In our runs of 2026-10-17 a 5-page scan of 2,522 KB reached 384 KB and four colour photo pages of 8,265 KB reached 412 KB for the closest target, 500 KB. Below about 15 KB per scanned page, small print starts to blur.
| Test file | Original | Target | Result | Fits? |
|---|---|---|---|---|
| 5-page scanned contract, 200 DPI | 2,522 KB | 1 MB | 895 KB | Yes |
| 5-page scanned contract, 200 DPI | 2,522 KB | 500 KB | 384 KB | Yes |
| 5-page scanned contract, 200 DPI | 2,522 KB | 200 KB | 148 KB | Yes |
| 5-page scanned contract, 200 DPI | 2,522 KB | 100 KB | 82 KB | Yes |
| 5-page scanned contract, 200 DPI | 2,522 KB | 50 KB | 34 KB | Yes |
| 4 full-colour photo pages | 8,265 KB | 1 MB | 827 KB | Yes |
| 4 full-colour photo pages | 8,265 KB | 500 KB | 412 KB | Yes |
| 4 full-colour photo pages | 8,265 KB | 200 KB | 150 KB | Yes |
| 4 full-colour photo pages | 8,265 KB | 100 KB | 91 KB | Yes |
| 4 full-colour photo pages | 8,265 KB | 50 KB | 39 KB | Yes |
“JPEG is a commonly used method of lossy compression for digital images, particularly for those images produced by digital photography.”
What can you do when pdf24 compress PDF to 600 KB cannot reach 600 KB?
A file that will not compress to 600 KB usually has too many pages or colour scans at high resolution. Remove pages the form does not need, rescan in grayscale at 150 DPI, split the document into parts, or rebuild it from the original photos, which shrinks every picture first.
- Remove the pages the portal does not need.
- Convert the PDF to grayscale, then compress again.
- Split the PDF and upload it in parts.
- Rebuild it with JPG to PDF from the original photos.
pdf24 compress PDF to 600 KB works in Chrome, Edge, Firefox and Safari on Windows, macOS, Linux, Android and iOS.
pdf24 compress PDF to 600 KB: frequently asked questions
Is pdf24 compress PDF to 600 KB free?
Yes. Compressing a PDF to 600 KB here costs nothing: no account, no watermark and no daily limit. The work runs on your own device, so there is no server bill to pass on, and you can repeat it as often as the form needs.
Will pdf24 compress PDF to 600 KB make the file exactly 600 KB?
The result is 600 KB or smaller, never larger. An exact byte count is not possible with image compression, so the tool keeps the largest result that still fits the limit and shows the final size before you download the file. If a portal still refuses it, type a target a few KB lower.
Does pdf24 compress PDF to 600 KB upload my file?
No. The browser reads the PDF with the File API and every step runs in JavaScript on your phone or computer. The result line reports 0 bytes uploaded, and nothing is stored anywhere, so there is nothing to delete afterwards. It also works offline once the page has loaded.
Does pdf24 compress PDF to 600 KB keep text selectable?
Only when the lossless save is enough. To reach a hard target, pages are redrawn as JPEG images, so text can no longer be selected or searched and links are lost. Run OCR afterwards if you need searchable text again, which also runs in the browser.
More pdf24 compress PDF to 600 KB tools and guides
pdf24 compress PDF to 600 KB: sources
- File API (MDN Web Docs) — MDN
- PDF format family (Library of Congress) — Library of Congress
- JPEG (Wikipedia) — Wikipedia