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Resize Signature Online

Crop a signature image and resize it to an exact width and height, with an optional file-size target — all inside your browser.

1 · Choose a signature image

A photograph of a signature on paper works best: crop tight to the ink, and the tool keeps the strokes rather than smoothing them away.

2 · Crop the margins

Your signature appears here once you choose a file.

3 · Choose the output size

Example sizes
These are common examples, not requirements. Every form sets its own rules, so check the one you are filling in.
How the size is applied
The height follows the width, so the signature is never stretched.

Output will be 300 × 100 px, the same shape as the crop.

4 · Format, file size and download

No signature chosen yet.

Format

Resizing happens in this browser. Your signature is not uploaded, stored or logged.

Your file is never sent to a server. It is read and processed by your own browser, and the results are not stored.

How to use it

  1. Choose a scan or photo of your signature.
  2. Drag the crop tight around the ink so the margins and the paper edge are gone.
  3. Type the width and height your form asks for, or start from an example size.
  4. Choose a format, add a KB target if the form has one, and download the result.

Limits worth knowing

  • The example sizes (140 × 60, 200 × 80, 300 × 100) are examples, not standards. Every form sets its own rules, and this tool cannot know what yours requires — check the instructions you were given.
  • The signature keeps its shape. “Keep the shape exactly that size” derives the height from the width, and “Fit inside the box” shrinks it until it fits — neither stretches it.
  • A file-size target is only available for JPEG and WebP. PNG is lossless, so it cannot be compressed to a KB target; a target that cannot be reached is reported rather than approximated.
  • Very low quality makes thin strokes break up and look ragged. The tool measures how much the output differs from your crop and warns when a setting changes it noticeably.
  • There is no background removal or “clean up” feature. A shadow, a fold or a yellow cast in the scan stays in the image; crop tightly and start from an even, well-lit capture instead.
  • No tool can promise that a particular form will accept your signature. What this one can do is produce exactly the dimensions and file size the form asks for.
  • Colour profiles and EXIF data are not carried into the resized file.

What forms usually mean by signature size

A signature field on a form is described in pixels: a box such as 140 × 60 into which the image has to fit. Some portals also cap the file at 20 KB or 50 KB, and a few want a specific format. Those three numbers — width, height, file size — are what this tool lets you hit exactly.

The crop matters more than the resize. A photograph of a signature on a full sheet of paper, cropped to the sheet, spends most of its pixels on blank paper. Cropping tight to the ink means the resized image uses its pixels on the strokes, which is why a tightly cropped 20 KB signature looks far better than a loosely cropped one at the same size.

Before you start, read the field you are filling in. If it says “maximum 200 × 80”, use Fit inside the box and one side may come out smaller — which is still within the rule. If it says “exactly”, keep the shape mode, because that is the mode that produces the exact numbers.

Keeping thin strokes readable

A signature is mostly thin lines, and thin lines are the first thing compression damages. Two things help: crop instead of shrinking, and give the output as few pixels to work with as the form allows while still being legible.

When a KB target is set, the encoder searches for the best quality that meets it. The result tells you whether the target was met, and how much the pixels changed compared with your crop. If the difference is large, the previews show it — a signature that no longer reads as your signature is worse than one that is a few kilobytes over the limit.

PNG is the safest choice for legibility because it is lossless. If a KB target forces JPEG or WebP, raise the dimensions a little rather than dropping the quality further: more pixels at moderate quality usually beats fewer pixels at low quality for line art.

What this tool does not do

It does not remove backgrounds, enhance contrast, straighten a photographed page or turn a blue pen black. Those effects look impressive in a preview and can change the strokes someone compares against a wet signature — and if the feature is not genuinely implemented, claiming it would be worse than leaving it out.

It does not tell you what your bank, exam board or visa portal accepts. Requirements differ and change, and only the form you are filling in is authoritative.

It does not upload anything. The image is decoded by the browser, cropped on a canvas in this tab, encoded by the browser, and discarded when you close the page. There is no server endpoint here that could receive it.