Compress a PDF to under 50 KB.

• UPPSC, photo (JPEG, not PDF): Ensure that the size of the scanned photo image is not more than 50KB and sign image is not more than 30KB. (UPPSC, photo and signature scanning instructions)
• IBPS, photo and left thumb impression (JPEG): Photo 20 KB – 50 KB; left thumb impression 20 KB – 50 KB. (IBPS CRP PO/MT-XVI notification, pp. 39–42)
• SSC CHSL 2026, signature (JPEG): Candidates are required to upload the scanned signature in JPEG/JPG format (10 to 20 KB). (SSC CHSL 2026 notice, ¶9.6)

A 50 KB limit is nearly always on an image, not a PDF: photos, signatures and thumb impressions. If your portal wants a JPEG, the photo and signature resizer makes it to the exact KB and pixels instead. Use this page when a portal wants a one-page PDF that small, such as a signature or ID scan it asks for as PDF.

• One dense typed page just fits, at 72 DPI: in our test a full A4 page of small type came out at 48 KB, readable but soft. A signature, an ID card or a certificate with large type has far less detail and comes out sharper.
• Two pages of anything but the sparsest content won't fit; the tool goes down to 72 DPI and then tells you the smallest it could make. Split them.
• Tick “Grey pages” for a colour scan of a black-and-white document: the tint of the paper is detail JPEG has to spend bytes on.
• The result is checked against 50 KB counting 1,000 bytes to the KB, which is the stricter reading; a 1,024-byte portal will accept it too.

Every page is redrawn as a JPEG at the sharpest DPI that fits, from 200 down to 72, so the file is only as small as it has to be. The tool tells you the DPI it settled on when it goes below 120.

• Crop before you scan: a signature or an ID card should fill the page, not sit in a corner of an A4 scan with white space costing bytes for nothing.
• Scan or photograph in flat light. Shadows and a grey cast are texture, and texture is what JPEG can't compress away.
• If it's an image the portal wants, don't make a PDF at all: the photo tool's custom size takes a KB range and gives you a JPEG.
• If the tool reports it couldn't get under 50 KB, it tells you the smallest it could make, so you know how far off you are; try grey, or one page at a time.

Photos of documents rather than a PDF? The images-to-PDF tool makes one PDF under the same limits, and an Aadhaar goes through the safe Aadhaar copy tool, which masks the number as well.