A signature resizer for online application forms
Recruitment exams, university admissions, scholarship portals and government job sites usually want a scanned signature and a photograph in a very particular shape: exact pixel dimensions, a file size between two KB values, JPG format. Miss any one and the upload is rejected. This signature resizer takes a phone photo of your signature, crops it tightly to the ink, turns it into clean black on white, and saves a JPG at the pixel size and KB range you enter.
It was built with Indian exam and job portals in mind, where wording like “signature 140 × 60 pixels, 10–20 KB” is typical — but requirements differ from notice to notice and change between years. The sizes listed in the tool are common examples, not official rules: always read your own exam notice and type its numbers. Everything runs in your browser, so your signature is never uploaded to us.
How to use the Signature Resizer
- Sign in the box size you need on plain white paper with a dark pen (use the ink colour your notice asks for), then photograph or scan it in good light.
- Drop the image on the upload area. Choose an example size or “My notice’s size”, and type the width, height and KB range from your notice.
- Keep “Clean up signature” ticked: the paper turns pure white, the ink pure black, and the image is trimmed to the signature. Move the Ink threshold slider if strokes look thin or specks remain.
- Check the badges under the preview — they confirm the file is inside your KB range — and read the exact byte count.
- Press “Download JPG” and upload the file to the form. Use the same steps with a photograph preset for your photo.
Signature Resizer features
Tight automatic crop
Finds the ink and trims the empty paper around it, leaving a small margin, so the signature fills the required box.
Clean black on white
An adaptive threshold removes shadows, paper texture and grey casts from phone photos — even when one side of the page is darker.
Exact pixels and KB range
Set the width, height, minimum and maximum KB; the tool finds the best JPG quality inside the range.
Minimum size padding
Tiny black-and-white signatures can be under a minimum like 10 KB. The tool can add an inert comment block to the JPG to reach it — the picture itself is unchanged.
DPI when a notice asks
Write 200 or 300 DPI into the JPG header when a form specifies it.
Editable presets
Every example size is just a starting point: change any number to match your notification.
Reading the requirements in your notice
Application notices normally state four things for each document. Copy them into the tool exactly:
- Dimensions in pixels, for example “140 × 60 pixels (width × height)”. Width comes first.
- File size range, for example “10 KB to 20 KB”. The tool keeps files under the maximum whether the portal counts 1 KB as 1,000 or 1,024 bytes, and at or above the minimum by either count.
- Format, almost always JPG/JPEG. Keep the output format on JPG.
- Other rules such as ink colour, “signature in running hand” or a ban on capital-letter signatures. The tool cannot check these, so read them carefully.
Converting centimetres to pixels
Some notices give the signature size in centimetres. Pixels = centimetres ÷ 2.54 × DPI. At 200 DPI, 3.5 × 1.5 cm is 3.5 ÷ 2.54 × 200 ≈ 276 by 1.5 ÷ 2.54 × 200 ≈ 118 pixels — which is the second example in the list. If the notice also states a DPI, set the same value in “DPI tag”.
| Size in cm | Pixels at 100 DPI | Pixels at 200 DPI | Pixels at 300 DPI |
|---|---|---|---|
| 3.5 × 1.5 | 138 × 59 | 276 × 118 | 413 × 177 |
| 4.0 × 2.0 | 157 × 79 | 315 × 157 | 472 × 236 |
| 3.5 × 4.5 (photo) | 138 × 177 | 276 × 354 | 413 × 531 |
Why uploads get rejected — and the fixes
- File too small: a clean black-and-white signature at 140 × 60 px is often only a few KB. Keep “Pad up to the minimum” ticked to reach a 10 KB minimum without changing the picture.
- File too large: lower the maximum KB or the pixel size; the tool lowers quality automatically to fit.
- Signature looks faint or broken: raise the Ink threshold, or sign again with a darker pen.
- Grey or shadowed background: keep “Clean up signature” ticked and photograph the paper in daylight without a shadow from your phone.
- Photograph rejected: use a recent photo on a plain light background; the passport photo maker helps with head size, and the visa photo maker handles digital visa photos.
Signature Resizer FAQ
How do I resize my signature to 10–20 KB?
Choose the example “Signature · 140 × 60 px · 10–20 KB” or type your own size, keep “Pad up to the minimum” ticked and download. The signature resizer keeps the JPG between the two limits and shows the exact byte count.
Are these the official sizes for my exam?
No. The presets are common examples only. Requirements vary by exam, employer and year, so always follow the dimensions and KB range in your official notification and type them into the tool.
How do I make my signature background white?
Keep “Clean up signature” ticked. It turns the paper pure white and the ink pure black, even in a phone photo with shadows. Adjust the Ink threshold if needed.
Is padding a file up to the minimum KB allowed?
The padding is an ordinary JPEG comment block that image viewers ignore; the picture and its pixel size do not change. If you prefer, untick it and use a larger pixel size or a higher quality instead, if your notice allows.
Can I resize my photograph with this tool too?
Yes. Choose the photograph example or “My notice’s size”, untick “Clean up signature”, and drag the preview to centre your face.
Is my signature uploaded anywhere?
No. The image is processed in your browser and never sent to a server — important for something as sensitive as your signature.