TNPSC accepts a photo between 20 KB and 50 KB. It is a range, not just a maximum. A file can be rejected for being too small as easily as for being too large. Here is why each happens and how to fix it.
Too big: reduce the dimensions first
A studio file shared on WhatsApp is usually 150–400 KB. A camera original can be several MB. People reach for a quality slider or a "compress to 50 KB" site, but the real problem is the pixel count.
Shrinking a 3000 × 4000 px photo to the required 130 × 170 px removes about 99% of the pixels. After that, a normal JPEG quality setting lands inside 20–50 KB on its own. Crushing the quality while the photo is still full size gives you a blurry face in a file that is still the wrong dimensions.
Two things that make files bigger: saving as PNG, which TNPSC doesn't accept anyway, and busy backgrounds. A plain white studio backdrop compresses to almost nothing.
Too small: start from the original
The "file too small" error usually appears after the photo has been through an online compressor, sometimes twice. Each round throws detail away, and you can't get it back by saving again at higher quality.
- Go back to the original studio file, not the compressed copy.
- Resize to 130 × 170 px once, at the highest quality that stays under 50 KB.
- Don't enlarge the image to gain KB. A 1000 × 1300 px photo may pass the KB check and then fails the pixel check.
Sometimes a very plain portrait still comes out just under 20 KB, even at top quality. Little detail means little data. The TNPSC photo compressor handles this by appending a JPEG comment block, a standard part of the file format that holds no image data. The file reaches the minimum without a single pixel changing.
"Compress to 100 KB" and other numbers
Searches for photo compressor 100 KB or 200 KB come from other exams. SSC, railway, bank and university forms all set their own limits. For TNPSC, anything over 50 KB is rejected. 30 or 40 KB is fine as long as the image is 130 × 170 px.
Likewise, "20 to 50 KB image width and height" has no single answer. KB and pixels are separate rules. For TNPSC the pixels are fixed at 130 × 170, and other dimensions you find online belong to other forms.
The file says 49 KB and still gets rejected
"KB" can mean 1,000 or 1,024 bytes, and your phone, your computer and the upload form may not agree. A file right on the edge can pass on one and fail on another. Aim for the middle of the range, around 30–40 KB, and the difference stops mattering. The tool shows the measured size after preparing, so you can see where the file landed before you download.
The signature has the same kind of range, 10–20 KB, and the same fixes apply. Its specific issues are in the signature guide.