Compress image to 20 KB

What 20 KB does to a photo, and to a signature

We compressed our 25 photos to 20 KB with the tool above. With Allow shrinking ticked all 25 fit, and every one was made smaller in pixels. With it unticked, 0 of 25 fit. A signature has the opposite problem: IBPS also sets a minimum, and at its preferred pixel size the file stays too small.

Photos at 20 KB with Allow shrinking ticked, by kind

Close-up textures lost the most: the lowest score was 0.634, for a photo cut to 383 × 216.

Source: our test on 2026-11-10 (harness eacd79c, site code eacd79c), headless Chromium 145 on a desktop Mac, 25 CC0 photos. Similarity is our own 8×8-block luma score (SSIM): 1.000 means no visible change. How we test

IBPS signature, 10 to 20 KB

Each file was cropped and resized to the pixels shown, then saved with the setting shown. In range means at least 10,240 bytes and at most 20,000 bytes. IBPS asks for JPG or JPEG, so the PNG row is for comparison only.

Source: our test on 2026-11-10 (harness eacd79c, site code eacd79c), headless Chromium 145 on a desktop Mac, 4 images we made. How we test

How to get a file under 20 KB

1. If the form gives a pixel size, resize the image to it first. If it gives only a KB limit, skip this.
2. Add one JPG, PNG or WebP image above (or a HEIC in Safari). The target is already 20 KB.
3. Leave Allow shrinking ticked, unless you resized to a fixed pixel size. No photo in our test fit 20 KB without it.
4. Press Compress image. Read the size and the pixel size under the result.
5. If the form also sets a minimum, check the result against it. The compressor does not raise a file to reach a minimum: it treats the target as a ceiling, never a floor, and adds no padding to grow it.
6. Download the JPG and upload it.

When 20 KB goes wrong

My photo looks blurry at 20 KB.

It had to lose pixels to fit. In our test the long side ended at a median 612 px, and close-up textures came out as small as 333 px. Check the pixel size under the result: if the form shows the photo small, this is expected. If you need more detail, crop away the background first so the bytes go to the subject.

The result says Target not reached.

Allow shrinking is off. Without it the quality stops at 0.36, and our photos then came out at a median 268.4 KB: 0 of 25 fit. Tick Allow shrinking, or resize the photo to the form's pixel size first.

IBPS says my signature file is too small.

At the preferred 140 × 60 px a signature holds very little data. Our files came out at a median 2,550 bytes with the compressor, and the largest file any setting made at that size was 9,447 bytes, short of the 10,240 bytes a 10 KB minimum can mean. Candidates report blurred, tiny signatures after upload (user reports, for example this Quora question). The notice calls the size preferred. At 420 × 180 px the compressor put 2 of our 4 files in range, and the converter at JPG quality 100 did it for 3 of 4 at 280 × 120 px. Check what your portal accepts before you change the pixel size.

Is 20 KB the same as 20,480 bytes?

Our compressor counts 1,000 bytes as one KB. None of the official pages above says whether a KB is 1,000 or 1,024 bytes. A target of 20 KB gives at most 20,000 bytes, which is under the cap either way. The minimum is the risk: if the portal counts 1,024 bytes, a 10 KB minimum needs at least 10,240 bytes, so check the size under the result.

The official rules

From the official pages, with the date each one shows. An archived page was not reachable from our test machine, so we read a saved copy.

The SSC signature has the same 10 to 20 KB range, with its size given in centimetres; it has its own page.

Other pages for this job: Compress image to 50 KB · Compress image to 100 KB · Compress image for SSC signature · Compress image · Resize first or compress? · Exam photo and signature guide