Signature Resizer
Resize a scanned signature to exact pixels like 300×80 and a KB range like 10–20 KB. Auto-crop, white background, JPG or PNG — free and never uploaded.
- No upload — 100% private
- Instant, on your device
- Free, no sign-up
- Works offline once loaded
How it works
How to use Signature Resizer
Sign on plain white paper with a dark pen, then snap a photo or scan it.
Drop the image here — the tool crops tightly to the ink and whitens the paper automatically.
Choose the pixel size and KB range your form asks for, such as 300 × 80 px and 10–20 KB.
Check the live preview, exact pixel size and final KB, then download the JPG.
Why use it
Why use our Signature Resizer tool
Auto-crop to the ink
Finds the edges of your signature and trims the empty paper around it, ignoring small specks of dust.
Clean white background
Turns grey, shadowy paper into pure white and darkens faint strokes while keeping blue ink blue.
Exact pixels, no stretching
Presets like 300 × 80, 140 × 60 and 3.5 × 1.5 cm at 200 DPI. Your signature is centred with white padding, never distorted.
Hit a KB range
Set a minimum and maximum such as 10–20 KB. Quality is tuned automatically and the final size is shown before you download.
Private by design
Your signature is processed in your browser and never uploaded — important for something that can be used to sign documents.
FAQ
Frequently asked questions
What size should my signature be for an online form?
It depends on the form. Many application portals ask for something like 300 × 80 px or 140 × 60 px and a file between 10 and 20 KB, but rules change — always follow the instructions printed on your form.
Why is my signature still under the minimum KB?
A small, clean signature compresses to very few bytes. The tool first raises the quality; if the file is still too small, it can add harmless padding (a JPEG comment) so it meets the minimum. The picture itself is unchanged.
Will my signature be stretched to fit 300 × 80?
No. The signature is scaled to fit inside the box and the remaining space is filled with white, so the letters keep their natural shape.
How do I get a transparent signature?
Turn on Clean background, choose No limit for file size, pick PNG and tick Transparent background. Transparent PNGs work well for pasting into Word or PDF documents.
Is it safe to upload my signature here?
Nothing is uploaded. All cropping, cleaning and compression runs on your own device, and the image disappears when you close the tab.
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