Compress a PDF for UPSC — certificates between 50 KB and 300 KB

How to use Compress PDF for UPSC

1. Choose the scanned certificate PDF. The Target size box shows 300 KB, which the tool counts as 300,000 bytes.
2. Keep If needed, convert pages to images to reach the size ticked; most certificates are scans.
3. Tick Greyscale (smaller for text documents) only for black-and-white certificates whose seal and signature stay readable in grey.
4. Press the Compress to … button.
5. Check the New size. It must read at most 293 KB (the tool’s display of 300,000 bytes) and, to clear the 50 KB minimum safely, at least 51 KB.
6. Download the file and rename it to the exact UPSC name, such as board_certificate.pdf, before you upload it.

UPSC’s document table

UPSC’s “Instructions for uploading documents” on upsconline.nic.in (dated July 2025 in the file’s properties, read on 27 October 2026) lists each document with its profile, format, size range and required file name:

The instructions add one blunt rule: a document will not be uploaded if any other file name, format or size is used. So a PDF for UPSC has to pass three checks at once: PDF format, a size inside 50–300 KB, and the right name.

What it does and when to use it

A certificate scanned on a modern phone or office copier is often well over 300 KB, because the scanner saves the page as a large, detailed colour image. This tool brings that file under 300 KB while keeping as much of the page as the budget allows. The photo, signature and ID card are JPG uploads, so they belong in the UPSC Photo & Signature Resizer and, for the ID card, Compress Image to 200 KB.

How it works

The file never leaves your device.

• At or under 300,000 bytes: the file comes back unchanged.
• Otherwise a lossless rebuild repacks the PDF’s internals without touching what is on the page.
• If that is not enough, each page is drawn again as a JPEG, starting at 150 DPI, and the tool searches JPEG quality between 35% and 85% for the largest result that fits.
• If 35% at 150 DPI is still too big, it picks a lower resolution from a fixed list (120, 100, 85, 72 DPI and lower) based on the size it measured.

Worked examples

A one-page matriculation certificate scanned at 600 DPI in colour. One page in 300,000 bytes is about 1.1 bits per pixel at 150 DPI on A4, enough for clear print. That budget lets the tool start at 150 DPI, and the method line tells you the resolution and quality it settled on.

A two-page caste certificate. Each page gets 150,000 bytes. If both pages are black text on white, ticking Greyscale leaves more of those bytes for detail.

A four-page disability certificate that will not fit at 150 DPI. Suppose the first attempt at 150 DPI and 35% quality comes to 520 KB. The tool computes 150 × √(300 ÷ 520) × 0.95 = 108.24 and moves to the next step at or below that, 100 DPI. Read the result at full size; if any line of the certificate blurs, rescan with plainer settings.

When the file is below the 50 KB minimum

Compression cannot help here, because removing bytes only takes you further from the floor. A PDF downloaded from an issuing authority’s website, or a very plain scan, can weigh less than 50 KB. Some honest ways up:

• Rescan the paper certificate at a higher resolution, such as 200 or 300 DPI, and in colour. Both make the image larger. Then compress to 300 KB if it overshoots.
• Convert the small PDF to a higher-resolution image PDF. Use PDF to JPG at 200 or 300 DPI, then JPG to PDF. The page looks the same, but it is stored as a detailed picture, so the file grows. The text is no longer selectable, which does not matter for an upload.
• Do not pad the file with blank pages or unrelated images. The reviewer has to see the certificate, and only the certificate.

Whichever way you go, check the final size again: at least 51 KB as the tool shows it, and no more than 293 KB.

When even the smallest result is too big

• Remove pages that are not part of the certificate, such as a covering letter or a blank back, with the PDF Page Deleter.
• Rescan with plainer settings: 150 or 200 DPI, greyscale if the document has no colour, cropped to the paper’s edge.
• Photograph the page flat in even light and rebuild it with JPG to PDF if the scanner’s output is very noisy.

What the tool cannot do

• It cannot rename your file; the output is called after your original with -300kb added, so rename it to the UPSC name yourself.
• It cannot keep text selectable once pages become images, and it warns you when that happens.
• It cannot make a faded or skewed scan legible.
• It cannot check that you are uploading the right certificate for the profile, or that the portal will accept it.

For the arithmetic behind page budgets, see the guide to compressing a PDF for an online form.