Resize a signature for forms and applications

How it works

1. Drop a scan or photo of your signature.
2. Set the required dimensions (for example 140 x 60 px), the maximum size (for example 20 KB) and the output format.
3. Choose a background color for JPG output (white is the usual choice).
4. Download a file that meets both constraints, or a clear explanation of the closest achievable result.

Common requirements

• 140 × 60 px / ≤ 20 KB — The most common signature specification on exam and visa portals.
• ≤ 20 KB — Byte ceiling on most signature upload fields — pair it with the pixels your form states.
• ≤ 10 KB — Tighter ceilings still found on older government portals.
• ≤ 50 KB — Signature boxes that accept a scan or a phone photo.
• White background — Required when the portal converts to JPEG and transparency would turn black.
• PNG, transparent — For portals that accept PNG and show the signature over their own background.

How to resize a signature for a form upload (140×60 px, under 20 KB)

Forms state two constraints at once — the classic signature 140x60 px and under 20 KB. Enter both numbers and the tool applies them in the right order: resize to the exact pixels, then search quality until the file fits the byte ceiling, then report what was achieved.

If a signature under 20 KB still looks blocky, the limitation is the form, not the tool: 20 KB leaves very little room for information. A clean white background, dark pen strokes and no desk or shadow in the frame are what make that ceiling comfortable instead of painful.

Format matters as much as size. A transparent PNG keeps a clean edge but usually needs more bytes; JPEG on a white background is typically the smallest. Both are one click apart here, and the background colour is yours to choose so flattened transparency never becomes a black box.

Requirements vary by portal, exam and country, which is why there are no region presets: resize signature for upload with the exact numbers from your own form. If the page already refused your file with a signature size too large error, the byte ceiling is the constraint to attack first.

Supported formats

JPEG, PNG, WebP, AVIF and photos of signatures. Transparent PNGs are supported and can be flattened onto a chosen background.

Best with files up to 50 MB. Hard safety limit 200 MB.

Privacy

Everything happens in your browser: the image is decoded, transformed and encoded locally. Nothing is uploaded, and no filename, pixel data or metadata is sent anywhere. Read more on the privacy page.

Technical methodology

• Pixel dimensions and the KB ceiling are applied in one pipeline: resize first, then optimize quality to fit the ceiling at the best quality that fits.
• Transparent signatures converted to JPEG are flattened onto the background color you choose, so no black boxes appear.
• No country- or form-specific preset pages exist by design: requirements vary and change, so the tool takes the exact numbers and explains the common cases.

Known limitations

• Common form requirement patterns vary — always enter the exact numbers from your form, not from a blog post.
• Very small KB limits combined with large pixels may force gray-scale-like quality on detailed scans; the report shows what was achieved.