Free, browser-based, no upload required
Reduce any image below 20KB entirely in your browser. Portals that enforce a 20KB limit often reject files at exactly 20KB, so this tool targets 18KB by default to give your submission a safe margin below the threshold.
Safe margin
Targets 18KB, not 20KB
Any format
JPEG, PNG, WebP, HEIC
No uploads
Files stay on your device
Drop image here to compress to 18KB
JPEG, PNG, WebP, AVIF, HEIC. All processing stays in your browser.
Default target is 18KB. If your portal requires a different limit, change the target size in the field above.
A 20KB ceiling is one of the strictest file size limits you will encounter on a form or portal. It most commonly appears on signature upload fields and legacy government systems that were built to serve users on very slow internet connections.
Digital signature uploads
Many online forms require a scanned signature image under 20KB. This is the most common real-world reason users encounter this limit, particularly on banking, legal and government forms.
Avatar and profile thumbnail fields
Older portal systems with fixed-size thumbnail slots often cap uploads at 20KB because the image is displayed at very small sizes and does not need high resolution.
Strict legacy government forms
Some state-level government portals in India, Bangladesh and other countries impose a 20KB ceiling on applicant photographs, particularly for older scholarship and subsidy application systems.
Low-bandwidth submission systems
Portals designed for rural or low-connectivity users sometimes enforce very tight file size limits across all uploaded assets to ensure the system remains accessible on slow connections.
Forms and portals that impose a 20KB ceiling are typically legacy systems built for low-bandwidth environments, or fields designed for small image types such as signature scans and thumbnail avatars. The limit is enforced server-side, meaning your file must be strictly below 20KB before you attempt to submit. Files at exactly 20KB are often rejected because the system checks for less than, not less than or equal to.
When a portal specifies a maximum of 20KB, any file smaller than 20KB will pass. You do not need to hit exactly 20KB. This tool targets 18KB by default, leaving a safe 2KB margin so your file passes even if the portal measures file size differently or has a slightly stricter internal threshold.
It depends on the type of image. A scanned signature or simple line drawing compresses to under 20KB with very little quality loss because these images have low visual complexity. A full-colour photograph at 20KB will show visible compression and reduced dimensions, but will remain clear enough for identity verification and form submission purposes.
JPEG, PNG, WebP, AVIF and HEIC are all supported as input. The output is JPEG or WebP. For portal submissions, always choose JPEG as the output format. It is universally accepted by every upload system including older government and banking portals.
No. All compression runs entirely in your browser using JavaScript and the Canvas API. Your image never leaves your device at any point. You can verify this by disconnecting from the internet after the page loads. The tool will still compress and download your image successfully.
Yes. Even a small reduction from 22KB to under 20KB is handled correctly. The binary search algorithm finds the highest JPEG or WebP quality setting that produces a file below the target, so small reductions like this work just as reliably as large ones. The tool targets 18KB by default, so you will have a comfortable margin below the portal limit.
