"Photograph must not exceed 100 KB." "Documents must be uploaded in PDF, under 200 KB." "Signature: 10 KB to 20 KB." Indian government portals, state PSC sites, university admission forms and bank KYC uploads all state a hard number, and they refuse a file that is over it by a single kilobyte. What none of them tell you is how to actually get your file to that number.
Why "low, medium, high" compression is the wrong tool
Most compressors offer you three quality presets and leave you to work it out. You pick medium, get 340 KB, pick maximum compression, get 40 KB and a blurry mess, and end up running the same file five times trying to land somewhere near the number on the instruction page.
The problem is that you are being asked the wrong question. You do not want "smaller" - you want a specific number, and within that number you want the sharpest, largest file that still fits. That is a search problem, and a computer is much better at it than you are with a dropdown.
The Compress to Exact Size tool takes the number instead of a vague quality setting. You type 100, or 20, or 47 if that is genuinely what your form says, and it searches for the highest quality that still comes in under your target - so you lose only as much quality as the limit actually forces, and not a bit more.
How to do it
- Open the Compress to Exact Size tool and drop in your PDF, JPG, PNG or WebP file.
- Pick a target from the presets - 20 KB, 50 KB, 100 KB, 200 KB, 500 KB, 1 MB, 2 MB - or type your own number in the box next to them. The custom box is the one to use for the odd limits real forms hand out.
- Leave "Keep the original dimensions exactly" unticked unless your form also specifies pixel dimensions. With it ticked, the tool is not allowed to shrink the picture, so a very small target may simply be unreachable.
- Press Compress, check the result, and download.
What actually happens to the file
For an image, the tool re-encodes it as a JPEG over and over at different quality levels, closing in on the highest one that still fits under your number. Only when even a low quality cannot get there does it start reducing the pixel dimensions, because losing resolution is a bigger sacrifice than losing a little JPEG quality and should be the last resort, not the first.
For a typical phone photo going to 100 KB, you will struggle to see any difference on screen. At 20 KB you will start to notice softness, and that is unavoidable - 20 KB is genuinely very little data for a photograph, no matter which tool you use.
The honest catch with PDFs
Hitting a hard size cap on a PDF is a different job from ordinary PDF compression, and it has a real cost you should know about before you use the output for anything important. To guarantee a specific size, every page has to be re-rendered as an image and rebuilt into a new PDF at whatever quality reaches your target. That means the text in the result is no longer text. It is a picture of text. Ctrl+F stops finding words, you cannot select or copy a line out of it, and anything that reads PDF text automatically will see an empty document.
For a form upload, a printout, or a scan you are emailing to an office, that is almost always fine - the person on the other end is looking at it, not searching it. But if you need the text to stay real, selectable text, use the regular Compress PDF tool instead. It shrinks the images inside the PDF and leaves the text layer alone, which keeps the document usable but cannot promise an exact final size. Those two things genuinely trade off against each other, and any tool claiming otherwise is not being straight with you.
When the form gives a range, not a ceiling
A lot of Indian exam forms specify both ends: "photograph 20 KB to 50 KB", "signature 10 KB to 20 KB". These portals check both. A clean, high-contrast scan of a signature can compress down to 6 KB, which looks perfectly fine to you and gets refused for being under the minimum - a rejection that makes no sense until you notice the lower bound.
For that case, use the Exam Photo and Signature Resizer instead. It takes both numbers, knows the published spec for SSC, IBPS, RRB, UPSC and others, and lands the file inside the range rather than just under the ceiling.
Sizes you are commonly asked for
| What you are uploading | Size commonly asked for | Where it comes up |
|---|---|---|
| Passport photo | 20-50 KB | SSC, RRB, IBPS application forms |
| Signature | 10-20 KB | Most exam and banking portals |
| Photo, larger allowance | Up to 100 KB | Many state PSC and university portals |
| Scanned certificate or marksheet | 100-500 KB | Document upload steps, scholarship portals |
| Full document set as one PDF | Up to 1-2 MB | Job applications, tender and KYC submissions |
Treat that table as a rough guide to what to expect, not as a specification. The number that matters is the one on your own form's instruction page, and it changes between portals and between cycles.
Getting a decent result at a small target
- Crop before you compress. Empty background around a face is data the compressor has to spend quality on. A tightly cropped head-and-shoulders photo at 20 KB looks far better than a full-length one squeezed to the same size.
- Start from the best original you have, not from a file that has already been compressed twice and forwarded on WhatsApp. Compression damage accumulates and cannot be undone.
- Photograph documents in even, bright light. Shadows and colour casts add noise, and noise is expensive - it eats the quality budget that should be going on the actual content.
- If a scanned document has to fit a small limit, greyscale usually beats colour. A black-ink-on-white marksheet gains nothing from colour data.
Nothing is uploaded
The whole thing runs inside your own browser, using its own image and PDF engines, so your file never leaves your device. That is not a policy we promise to follow - the tool has no upload step in it at all. It is also why the tool is free and needs no account: nothing of yours is stored, so there is nothing to charge for.