How small do the dimensions have to go to fit {{kb}} KB?

Around {{pw}} by {{ph}} for a detailed photograph, and much larger — around {{fw}} by {{fh}} — for a signature or a flat scan. The tool measures your file instead of guessing.

Resize an image to 300 KB

Set to 300 KB already. Choose a photo and the tool shrinks the frame — and the quality if it has to — until the file sits just under 300 KB.

Choose an image or drag one onto this box — JPG, PNG, WebP, GIF or HEIC

Target size KB Maximum width If quality alone cannot get there

Choose an image and it will be compressed here, in this browser. Nothing is uploaded.

Your image is never uploaded. Compression runs in this browser using the canvas API, and there is no server to send it to. This tool is provided free and without warranty — open the result before you submit it anywhere.

What 300 KB means in pixels

300 KB still has a frame. It is large enough for a full-width web image or a detailed photograph at moderate dimensions, so most pictures reach it by giving up a little width rather than being crushed. The number on the form is still a ceiling, not a target to hit exactly.

Why shrinking the frame beats crushing the quality

A 4000-pixel phone photo forced into 300 KB on quality alone turns to mush, because there are too many pixels to describe. Dropping the width first — 800, 600, 400 — keeps edges readable. The tool does that when quality alone cannot get under the limit.

Your image is never uploaded

The resize happens in your browser. The image is never transmitted, never stored, and disappears when you close the tab — which matters, because a file with a size limit attached is usually an identity document.

What fits inside 300 KB

A JPEG spends bytes on detail, so the number of pixels 300 KB can hold depends entirely on how busy the picture is. These are the rough budgets, and they are why a signature can stay large while a photograph of the same size limit has to shrink.

Kind of image	Pixels it can afford	Roughly, at 4:3
Signature or line drawing	6,144,000	about 2,860 × 2,150
Passport or ID photo	2,560,000	about 1,850 × 1,390
Scanned document page	1,536,000	about 1,430 × 1,070
Detailed photograph	930,909	about 1,110 × 830

Estimates from typical JPEG output at everyday quality. A detailed photograph gets about 930,909 pixels to work with at 300 KB — near enough 1,110 × 830. Anything bigger has to give up either dimensions or detail, and dimensions are almost always the better thing to give up.

Common questions

How do I resize a photo to 300 KB?

Choose the file on this page. The target is already 300 KB. The tool drops quality first and then the dimensions, so the file lands just under the limit instead of overshooting a form that will reject it.

What width and height fit in 300 KB?

It depends on how busy the picture is. A detailed photograph needs fewer pixels than a signature at the same file size. The table on this page is the working estimate; the tool measures your actual file.

How small do the dimensions have to go to fit 300 KB?

Around 1,110 by 830 for a detailed photograph, and much larger — around 2,860 by 2,150 — for a signature or a flat scan. The tool measures your file instead of guessing.

Why does the resized file sit just under 300 KB instead of on it?

Because the form rejects anything over 300 KB. The tool treats the number as a ceiling and stops once it is close, rather than risking an overshoot that gets the upload bounced.