Compress PDF to 100 KB

A 100 KB limit is the tightest one you will commonly meet on application forms. It is usually meant for a single scanned page: a signature sheet, an ID card scan, a category certificate or a one-page letter. This page is preset to 100 KB, so you only need to pick the file and run it.

What 100 KB really means here

Dokurapi counts 1 KB as 1000 bytes, so 100 KB is 100,000 bytes. The compressor does not aim for exactly that number. It aims for 94% of it, which is 94,000 bytes. Some upload systems count 1 KB as 1024 bytes and others as 1000, and the 6% margin covers that gap so you are not rejected by a few hundred bytes.

Realistic expectations for 100 KB

The tool renders each page to an image and rebuilds the PDF with JPEG pages. It tries four render scales (1.2, 1.0, 0.82 and 0.68) and three JPEG qualities (78%, 64% and 50%), stopping at the first combination that fits. What that means in practice:

• One page: a clean scan or typed page usually fits, often at a fairly high setting.
• Two or three pages: often possible, but small print may soften. Zoom in and read it before you upload.
• Many scanned pages: may not reach 100 KB while staying readable. The tool will say the target was not met and still hand you the smallest version.

A page full of colour photos or dark backgrounds is harder to shrink than a white page with black text. Scanning in greyscale, cropping away the empty border, and avoiding shadows from a phone camera all help.

Check before you upload

A file under the limit is useless if the reviewer cannot read your registration number. After compressing, open the PDF and zoom to 100% or more. Look at the smallest text on the page: dates, serial numbers, stamps and signatures. If anything is blurred, a smaller page count will help more than another round of compression.

Also remember that the compressed copy is image-only. Text cannot be selected, links stop working, and any digital signature is removed. Keep the original file for your own records; it is never altered.

When the file still does not fit

1. Remove pages the form did not ask for, such as blank backs or instruction sheets.
2. Split the document if the portal offers several upload slots.
3. If you started from phone photos, crop each photo tightly, combine them with photo to PDF, then compress again.
4. If the form actually allows more, try the 200 KB compressor for a sharper result.

Limits vary by organisation and by year, so treat the receiving portal's current instruction as the final word. Nothing you select here is uploaded, and there is no account or usage cap.