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Resize and clean up a signature image

Sign on white paper, take a photo and add it here. The tool trims the blank margins, whitens the paper and keeps the file at 20 KB or less, with sizes you can adjust.

1. Add your signature

2. New size

Units
px
px

3. File size and format

Maximum file size

Saved as JPG. Kept under 20,000 bytes, so it passes whether a site counts 1 KB as 1,000 or 1,024 bytes.

Add a photo or scan of your signature.

Check the size and file limits in your form's instructions before uploading.

How to prepare your signature image

  1. Sign and take a photo

    Sign with a dark pen on plain paper and take a photo in good light, or scan it. Any of JPG, PNG, WebP or HEIC works.

  2. Add the photo

    Signature mode is on when this page opens: Trim blank margins and Whiten background are switched on, and the maximum file size is 20 KB.

  3. Enter the size your form asks for

    Set the width and height in pixels, cm, mm or inches using the size in your form's notice. Switch off Trim blank margins or Whiten background if the result looks wrong.

  4. Check the preview and the KB

    The tool shows the final size in KB and pixels. Change the KB limit if your form states a different one.

  5. Download the JPG

    Save the file and upload it to your form.

What is different in signature mode

  • Trim blank margins

    The image is cropped automatically to the ink, so your signature fills the frame instead of floating in white space. This is on by default.

  • Whiten background

    Light-grey paper is turned white, which gives a cleaner result than a plain photo. This is on by default.

  • 20 KB limit pre-set

    The maximum file size starts at 20 KB and the output is a JPG. You can change the limit if your form says otherwise.

  • Your own dimensions

    Sizes stay adjustable in pixels, cm, mm or inches, so a wide, short signature box is easy to match.

  • Stays on your device

    Your signature is processed in your browser and is not uploaded. There is no sign-up and no watermark. Free to use.

What signature mode sets

Trim blank marginsOn by defaultCrops automatically to the ink
Whiten backgroundOn by defaultTurns light-grey paper white
Maximum file size20 KBChangeable
Output formatJPGSaved as signature-<width>x<height>.jpg
Size unitsPixels, cm, mm or inchesAdjustable; DPI choice appears for cm, mm and inches
Accepted imagesJPG, PNG, WebP and HEICUp to 25 MB and 50 megapixels

Signature size and KB limits differ by form. Take the figures from your form's notice. This tool only helps you meet them.

Frequently asked questions

How do I make a signature image for an online form?

Sign on plain white paper, photograph it in good light and add the photo here. The tool trims the margins, whitens the background and keeps the file at 20 KB or less. Then set the size from your form's notice and download.

What size should my signature be?

Your form's notice states it, and it varies from form to form. Enter that width and height in pixels, cm, mm or inches. This page does not state any exam's requirements.

What does Trim blank margins do?

It crops the picture to the ink of your signature, removing empty paper around it. Turn it off if you want to keep the margins.

What does Whiten background do?

It turns light-grey paper white so the signature stands out. It works best with a dark pen on plain paper. If it affects a light signature, switch it off.

Can I use a different KB limit?

Yes. The limit starts at 20 KB but you can choose another preset or enter a custom number of KB.

Can I upload a photo taken on an iPhone?

Yes, HEIC photos are accepted along with JPG, PNG and WebP.

Is my signature uploaded or stored?

No. The image is processed in your browser and is not uploaded. Location data is not included in the saved file either.

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