How to photograph or scan your signature for an exam form
A clean signature image is mostly decided before you open any app: the paper, the pen, the light and how you hold the phone. Get those right and resizing to 10 or 20 KB keeps every stroke readable.
Sign in black ink on plain white paper, larger than the final size. Photograph it straight from above in daylight, with no flash and no shadow. Crop tightly around the signature, then resize to the pixels and KB your form asks for, which is commonly 10 to 20 KB.
What you need
- Plain white paper, unruled and without a coloured tint. Lines and textures show up after compression.
- A black pen that writes a solid, even line, such as a gel or felt-tip pen. A faint ballpoint line can break up when the file is compressed to 10 KB. Some notifications allow blue ink as well; check yours.
- Daylight from a window, or a bright room light behind you rather than above the paper.
- A phone camera or a scanner. Either works; the steps differ slightly below.
Step 1: Sign larger than the final size
Forms usually want a wide, short signature image, commonly around 140 × 60 pixels, a shape of roughly 7 : 3. Sign inside an imaginary box of about 7 × 3 cm, a little larger than you would on a form. A larger original keeps more detail when it is shrunk, and leaves room to crop.
Sign in your normal running hand. Several boards reject signatures written entirely in capital letters.
Step 2: Light it evenly
Place the paper flat on a table near a window. Turn off the flash: it creates a bright spot in the middle and a dark edge around it. Watch for the shadow of your hand or phone falling across the paper, which is the most common reason a signature comes out grey.
Step 3: Photograph it straight on
- Hold the phone parallel to the paper, directly above the signature. A tilted phone turns the rectangle into a trapezoid and slants the strokes.
- Step back and zoom in slightly (about 2x) instead of holding the phone close. This reduces distortion and keeps your shadow off the page.
- Tap the signature to focus, then take two or three shots and keep the sharpest.
If you use a scanner instead, scan in greyscale at 300 DPI and save as JPEG. That gives more than enough detail to resize down.
Step 4: Crop tightly
Crop so the signature fills the frame with only a thin white margin. Large white borders waste the few kilobytes the form allows and make the signature look tiny once resized. Keep the crop roughly the shape of the final image so it does not get stretched.
Step 5: Clean up and resize
If the paper looks grey, raise the contrast or convert the image to greyscale so the background turns white and the ink stays dark. Then resize to the pixel size and KB range in your notification. Our signature resizer guide lists common limits by exam, and the resizer applies them for you.
Mistakes that get signatures rejected
| Mistake | What happens | Fix |
|---|---|---|
| Lined or coloured paper | Lines and tint remain after compression | Use plain white paper |
| Thin, faint pen | Strokes break into dots at 10 to 20 KB | Use a pen with a solid black line |
| Signature in capitals | Rejected by boards that forbid it | Sign in your normal running hand |
| Shadow or flash glare | Grey background, uneven ink | Daylight, flash off, phone held higher |
| Photo taken at an angle | Slanted, distorted strokes | Hold the phone parallel to the paper |
| Too much white space | Signature looks tiny and faint | Crop close around the signature |
| Image sent through WhatsApp first | Already compressed; may drop below the minimum KB | Use the original photo from the camera |
Thumb impressions and handwritten declarations
The same approach works for a left thumb impression and a handwritten declaration: plain white paper, even light, straight-on photo, tight crop. Each has its own size and format, though, so do not reuse the signature settings. See the thumb impression and handwritten declaration guides.
Frequently asked questions
What pen should I use to sign for an exam form?
A pen that writes a solid, even black line, such as a gel or felt-tip pen. Faint ballpoint lines can break up when the image is compressed to 10 or 20 KB. Check whether your notification also allows blue ink.
Should I use a scanner or my phone?
Either works. With a phone, use daylight, no flash, and hold the phone parallel to the paper. With a scanner, scan in greyscale at 300 DPI and save as JPEG.
Why does my signature look grey after resizing?
Usually a shadow or uneven light on the paper. Retake it in daylight with the flash off, or raise the contrast so the background turns white before resizing.
Can I sign in capital letters?
Avoid it. Several boards, including banking exams, reject a signature written entirely in capital letters. Sign in your normal running hand.
How big should I sign on the paper?
A little larger than you would on a form, inside roughly a 7 x 3 cm area. A larger original keeps more detail when it is resized down to the form's pixel size.
Related guides
Resize your signature to the exact KB
Pick your exam and the pixel and KB limits are applied for you. Everything runs in your browser, so the file never leaves your device.
Open PhotoResizer →