Will it always get under 20 KB?

Not always, and it will tell you when it cannot. The search stops at quality 30, because below that a JPEG stops being a smaller version of your photograph and becomes a blocky approximation of it. If 20 KB is unreachable at that floor, you get the smallest sensible file and a clear statement that the target was missed — the fix is then to reduce the dimensions, which is far more effective than pushing the quality lower.

Is my photo uploaded?

No. Every encoding pass runs in your browser, so the file never leaves your device — and there are several passes, all of them local. Nothing about your photograph is sent anywhere.

Why does this take longer than normal compression?

Because it encodes the image several times. Compressing to a fixed quality is one pass; hitting a size target means trying a quality, measuring the result, and narrowing in. It usually settles within about six passes, which is a second or two for a typical photograph.

Can I change the target?

Yes — the field under the result is editable. This page exists because 20 KB is what people search for, but if it turns out your real limit was different, change the number and convert again rather than hunting for another page.

Does the result go slightly over sometimes?

No. The search only keeps results that measure under the target, so what you download is under it. Nothing is estimated — every candidate is a real encode that we measured.

Compress JPG to 20 KB — Free, No Upload

Reaching 20 KB without wrecking the picture

The only route to 20 KB that keeps a photograph looking like a photograph is to make it small in dimensions as well as in quality. An image 400 or 500 pixels wide at a moderate quality reaches 20 KB comfortably; the same picture at 2000 pixels wide does not, at any quality worth using.

This is usually fine, because the requirement almost always comes with a matching display size. Forms asking for a 20 KB photograph are asking for a thumbnail or a small profile picture, and nothing will ever draw it larger than a couple of hundred pixels. Set the resize control to 800 px or below and the target stops being a fight.

What a 20 KB JPG looks like

If you leave the dimensions alone, expect the search to bottom out at our quality floor and report that it could not reach the number. That is deliberate. Below about quality 30 a JPEG stops being a compressed photograph and becomes a blocky approximation of one, and producing that silently to satisfy a number would answer the request while failing the person who made it.

Government and institutional forms are the usual source of a 20 KB limit, and they are also the usual source of a matching pixel limit further down the same page. Reading that second requirement first tends to make the first one easy.

Why a target size is a search and not a setting

A JPEG encoder takes a quality number, not a file size. The relationship between the two depends entirely on the picture — a photograph of a brick wall and a photograph of a clear sky at the same quality and the same dimensions differ in size by a factor of ten, because one is full of detail and the other is nearly empty.

So there is no formula. We encode at a quality, measure the result, and adjust — narrowing in on the highest quality that still fits under 20 KB. It costs a handful of encoding passes, which is why this takes a moment longer than compressing to a fixed quality, and it is the only honest way to answer a question posed in kilobytes.

How to compress a JPG to 20 KB

Drop your JPG onto this page, or click to choose one.
We encode at several qualities and keep the best one under 20 KB, in your browser.
If the target could not be reached, the page says so rather than handing you something unusable.

Compressing to 20 KB: common questions

Will it always get under 20 KB?: Not always, and it will tell you when it cannot. The search stops at quality 30, because below that a JPEG stops being a smaller version of your photograph and becomes a blocky approximation of it. If 20 KB is unreachable at that floor, you get the smallest sensible file and a clear statement that the target was missed — the fix is then to reduce the dimensions, which is far more effective than pushing the quality lower.
Is my photo uploaded?: No. Every encoding pass runs in your browser, so the file never leaves your device — and there are several passes, all of them local. Nothing about your photograph is sent anywhere.
Why does this take longer than normal compression?: Because it encodes the image several times. Compressing to a fixed quality is one pass; hitting a size target means trying a quality, measuring the result, and narrowing in. It usually settles within about six passes, which is a second or two for a typical photograph.
Can I change the target?: Yes — the field under the result is editable. This page exists because 20 KB is what people search for, but if it turns out your real limit was different, change the number and convert again rather than hunting for another page.
Does the result go slightly over sometimes?: No. The search only keeps results that measure under the target, so what you download is under it. Nothing is estimated — every candidate is a real encode that we measured.

Sometimes the better answer is a different format — especially for a photograph stored as JPG.