How to use pdf24 compress PDF to 25 MB 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 25 MB target. Exact size is preselected with 25600 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 25 MB with pdf24 compress PDF to 25 MB?
A 25 MB 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 25 MB fits about 1422 scanned pages. Colour photos need the most room per page.
| Pages | Budget per page | Typed text | Scanned pages |
|---|---|---|---|
| 1 | 25,600 KB | Fits easily | Fits easily |
| 2 | 12,800 KB | Fits easily | Fits easily |
| 3 | 8,533 KB | Fits easily | Fits easily |
| 5 | 5,120 KB | Fits easily | Fits easily |
| 10 | 2,560 KB | Fits easily | Fits easily |
| 20 | 1,280 KB | Fits easily | Fits easily |
pdf24 compress PDF to 25 MB 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 25 MB 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 25 MB for typed documents
Files exported from Word or a browser are mostly text and fonts. They often fit 25 MB after the lossless save alone, with text still selectable.
pdf24 compress PDF to 25 MB: how kilobytes are counted
The tool counts 1 KB as 1,024 bytes, the stricter way, so a result shown as 25 MB also passes portals that count 1,000 bytes per KB.
How small can pdf24 compress PDF to 25 MB go and stay readable?
Compression to 25 MB stops at the first setting that fits. In our runs of 2026-10-17 a 5-page scan of 2,522 KB reached 895 KB and four colour photo pages of 8,265 KB reached 827 KB for the closest target, 1 MB. 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 25 MB cannot reach 25 MB?
A file that will not compress to 25 MB 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 25 MB works in Chrome, Edge, Firefox and Safari on Windows, macOS, Linux, Android and iOS.
pdf24 compress PDF to 25 MB: frequently asked questions
Is pdf24 compress PDF to 25 MB free?
Yes. Compressing a PDF to 25 MB 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 25 MB make the file exactly 25 MB?
The result is 25 MB 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 25 MB 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 25 MB 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 25 MB tools and guides
pdf24 compress PDF to 25 MB: sources
- File API (MDN Web Docs) — MDN
- PDF format family (Library of Congress) — Library of Congress
- JPEG (Wikipedia) — Wikipedia
- Gmail attachment size limit (Google) — Google
- Outlook attachment size limits (Microsoft) — Microsoft