Published August 31, 2026

How to Prepare a Signature Image for an Online Form

A signature may be rejected even when the writing looks correct. Online forms can check its format, pixel dimensions, aspect ratio and file-size range. Starting with a clean source image makes every later step easier.

1. Sign on clean white paper

Use dark blue or black ink unless the receiving instructions specify something else. Leave enough space around the writing so it is not clipped, but avoid photographing an entire sheet of paper.

2. Use even lighting

Place the paper near soft daylight or under even indoor lighting. Avoid shadows from the phone and bright reflections. Hold the camera parallel to the paper so the signature does not become skewed.

3. Crop unnecessary space

Remove most of the blank paper while keeping every stroke visible. A close crop gives the signature more useful pixels and makes it easier to remain readable after compression.

4. Resize and enhance the signature

Open the PicLiva Signature Resizer. The tool places the writing on a 600 × 200 pixel white canvas, converts it to grayscale, increases contrast and exports a compressed JPG. Select the KB maximum shown by the form.

5. Check the exact requirement

Do not assume every portal accepts the same dimensions or 20KB limit. Some require a range such as 10–20KB, a different width and height, or a specific format. If the required dimensions differ, use the Image Resizer or exact cropper.

6. Inspect the downloaded result

• Every stroke should be visible.
• The writing should not touch the edges.
• The background should be clean and readable.
• The file format should match the instruction.
• The dimensions and KB value should both fall within the allowed limits.

7. Keep the signature private

A signature is sensitive personal information. PicLiva processes the selected image inside your browser, but you should still avoid sharing the downloaded file publicly and remove unnecessary copies from shared devices.