Four uploads, four rules: getting the photo, signature, thumb impression and declaration right on a bank exam form

Many bank and insurance recruitment forms in India ask for the same four scanned images: a photo, a signature, a left thumb impression and a handwritten declaration. Each one has its own pixel size and its own KB range, and two of them mention DPI. Get any of them wrong and the form throws an error or, worse, accepts something that gets your application questioned later.

I went through the current NICL Administrative Officer advertisement (2026-27) line by line, because it spells all four out. Online registration for it runs from 8 to 28 Oct 2026. Other forms that ask for these four documents set their own numbers, so read your own notice, but the traps are the same.

What the advertisement actually says

From the NICL AO 2026-27 detailed advertisement, listed on the official recruitment page at https://nationalinsurance.nic.co.in/recruitment:

Document	Pixels (as written)	File size	Other rules
Photograph	200 × 230 (preferred)	20 KB to 50 KB	Recent colour passport-style photo, light (preferably white) background
Signature	140 × 60 (preferred)	10 KB to 20 KB	Black ink on white paper, not in capital letters
Left thumb impression	240 × 240 at 200 DPI (preferred), "i.e. 3 cm × 3 cm"	20 KB to 50 KB	JPG/JPEG, black or blue ink on white paper, not smudged
Handwritten declaration	800 × 400 at 200 DPI (preferred), "i.e. 10 cm × 5 cm"	50 KB to 100 KB	JPG/JPEG, English, your own handwriting, black ink, not in capital letters

The declaration text it gives is:

I, ___________ (Name of the candidate), hereby declare that all information submitted by me in the application form is correct, true and valid. I will present the supporting documents as and when required.

It also says the form shows an error if the file size and format aren't as prescribed, and that you'll capture a live photo by webcam or phone during the application, in addition to the uploaded one.

Notice that every file has a minimum as well as a maximum. That's the part that catches people.

Gotcha 1: the cm and the pixels don't agree

DPI is just the bridge between centimetres and pixels: pixels = cm ÷ 2.54 × DPI.

• 3 cm at 200 DPI is 236 px, not 240.
• 10 cm at 200 DPI is 787 px, not 800.
• The photo is also described elsewhere in the advertisement as 4.5 cm × 3.5 cm. At 200 DPI that would be about 276 × 354 px, nowhere near 200 × 230.

So if you type "3 cm, 200 DPI" into a resizer, you'll get 236 × 236 and be slightly off. When a notice gives both, use the pixel numbers. They're the precise ones.

Gotcha 2: a clean scan is too small

A 140 × 60 signature in black ink on white paper is mostly white. As a JPEG it compresses to a few KB, below the 10 KB minimum. Same for a 240 × 240 thumb impression against the 20 KB minimum. My 140 × 60 test signature came out at 1,137 bytes, and a 240 × 240 test thumb at about 5.7 KB.

You can't fix that by scanning worse. The honest fix is padding: a JPEG can carry a comment segment that image viewers ignore. Adding comment bytes raises the file size without changing a single pixel. I checked this by comparing pixels before and after padding: zero difference.

Gotcha 3: KB vs bytes at the top end

Ranges like "20 KB to 50 KB" don't say whether 1 KB is 1000 or 1024 bytes. A file of 50,500 bytes is under 50 × 1024 but over 50 × 1000. Aim for the middle of each range rather than the edge.

My workflow for the four files

Everything below uses free tools. The commands use ImageMagick (magick) and ExifTool (exiftool), both free for Windows, macOS and Linux. I ran them on Linux; the padding one-liner needs a Mac or Linux terminal because it uses printf.

0. Scan or photograph them properly. White paper, daylight or a bright lamp, no shadows. The advertisement asks for a scanner at least 200 dpi in true colour, cropped to the edge of the item. With a phone, shoot straight down. Write the declaration in normal joined or print handwriting, not capitals.

1. Crop tight. Crop each image to the edge of the photo, signature, thumb or declaration. Any white border is wasted pixels. Crop to roughly the right shape (for example 7:3 for the 140 × 60 signature) so the next step doesn't stretch anything.

2. Resize to the exact pixels and set the DPI. In GIMP: Image > Scale Image, units in px, type the size from the table. Then Image > Print Size and set the resolution to 200 pixels/in before exporting as JPEG. Windows Paint and macOS Preview can resize by pixels too, but they don't let you set DPI. With ImageMagick, one line per file:

magick thumb-scan.jpg -resize 240x240! -units PixelsPerInch -density 200 -quality 92 thumb.jpg
magick decl-scan.jpg -resize 800x400! -units PixelsPerInch -density 200 -quality 92 declaration.jpg
magick sign-scan.jpg -resize 140x60! -quality 95 signature.jpg
magick photo-scan.jpg -resize 200x230! -quality 92 photo.jpg

The ! forces the exact size. Without it, ImageMagick keeps the aspect ratio and you may end up a few pixels short.

3. Check the bytes, pixels and DPI. File properties on Windows, Get Info on a Mac, or:

exiftool -FileSize# -ImageSize -XResolution -ResolutionUnit thumb.jpg

-FileSize# prints the exact byte count, which avoids the KB question from Gotcha 3.

4a. Too big? Cap it. Lower the JPEG quality in GIMP's export dialog, or let ImageMagick search for the highest quality that fits under a ceiling. Leave some headroom:

magick photo.jpg -define jpeg:extent=48kb photo-capped.jpg

4b. Too small? Pad it. Add a comment of blank characters roughly equal to the missing bytes, plus a little:

exiftool -Comment="$(printf '%*s' 10000 '')" signature.jpg

That took my 1,137-byte signature to 11,141 bytes, safely over 10 KB under either definition, with identical pixels and the 200 DPI header untouched. ExifTool keeps a backup copy named signature.jpg_original; upload the one without the suffix. One comment segment holds up to about 64 KB, which covers every gap in this table.

Gotcha 4: re-encoding can drop the DPI

Any step that re-encodes the JPEG can rewrite its header. In my testing, a browser-based compressor that re-encodes through a canvas didn't keep 200 DPI in its output. The pixels and bytes were right, but the DPI value was gone. If that happens, put it back after the last step:

exiftool -JFIF:XResolution=200 -JFIF:YResolution=200 -JFIF:ResolutionUnit=inches thumb.jpg

That only edits header fields and doesn't touch the pixels. The advertisement calls 200 DPI "preferred for required quality" and I can't tell you whether the portal reads the field, so treat this as belt and braces.

In range and still refused

• Rename the file. One word, no spaces or special characters, like photo.jpg. On a NICL AO thread on r/bankingexam, that alone fixed a photo that was already in the required range. The guideline's own example name is image01.jpg.
• Make it a real JPEG. Renaming a PNG, WebP or iPhone HEIC file to .jpg doesn't convert it. Open it and export or save it as JPEG.
• Brighten it onto white. If the form complains about the image quality, raise the brightness, crop tight and make the background pure white. A black and white filter works well on a signature.
• Fix a sideways preview. One applicant's declaration showed up rotated 90 degrees after upload on the IBPS site. Phone photos often store rotation as a tag rather than in the pixels, and some viewers ignore the tag. Rotate the image in an editor and save a new copy, or run magick declaration.jpg -auto-orient declaration-upright.jpg, so the pixels themselves are upright.
• No capitals. The advertisement says a signature or declaration in capital letters won't be accepted, and one candidate reported being turned away at an SBI PO exam centre for uploading their name in capital letters as the signature. Copy the declaration text word for word in your normal handwriting.
• Try another browser. If the file checks out and the form still errors, a different browser or a private window rules out a cached page or a browser quirk.

Before you press final submit

The advertisement says you can edit the application and re-upload an image if it isn't clearly visible, before you submit. Use that. Look at each preview on the form itself: is the face clear, is the signature readable, is the thumb ridge pattern visible and not a black blob? A file that passes the size check but shows a smudge is still a problem, and the advertisement is clear that change requests after submission won't be entertained.

I built ToolOcean, a set of browser-based file tools. Its exact-size compressor does steps 4a and 4b without a terminal: you set a ceiling and a minimum, and it pads the JPEG if it lands under the minimum. The files stay on your device: https://toolocean.co/compress-image-to-50kb

Drafted with AI help, tested and checked by me.