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Image4 min readUpdated 21 October 2026Steps checked against the tool on 21 October 2026

How to resize an image to a size in KB

Online forms often say a photo must be "under 50 KB". That is a limit on file size: how much storage the file uses. It is different from the image's width and height in pixels, such as 200 × 230.

Resize Image to KB treats your target as a maximum. It finds the best quality that fits under it, and reduces the pixel dimensions only when that is needed or when you ask it to.

Free tool

Resize Image to KB

Works in your browser. No signup.

Resize an image to KB
  1. Step 1Choose image
  2. Step 2Pick target KB
  3. Step 3Resize Image
  4. Step 4Download Image

Step by step

  1. 1

    Choose your image

    JPG, PNG and WebP images are accepted. The image is processed in your browser.

  2. 2

    Pick a target size

    Choose 20 KB, 50 KB, 100 KB or 200 KB, or Custom to type any size in KB.

  3. 3

    Set advanced options if needed

    Under Advanced options you can set a maximum width or height (the aspect ratio is always kept), the output format, and whether to keep dimensions or quality when shrinking.

  4. 4

    Resize and download

    Click Resize Image. Check the before and after sizes, the new dimensions and the preview, then click Download Image.

File size and pixels are different

The tool shows both: the file size before and after, and the dimensions, for example 1200×1600 → 600×800. If a form asks for exact pixel dimensions as well as a KB limit, use Form Ready Image, which handles both together.

Limitations to know

The target is a maximum. The tool does not make a file larger to meet a minimum size.

By default a PNG is saved as JPG so it can reach small sizes, and transparent areas become white. WebP stays WebP. You can choose a different output format under Advanced options.

If the tool cannot reach your target, check the reported output size and preview. You may need a larger target or different settings.

HEIC photos are not accepted here. Convert them with HEIC to JPG first.

Questions

Why does my 20 KB photo look blurry?

Very small targets need strong compression. If the form allows a larger size, use it. A plain background and even lighting also help a photo stay clear at small sizes.

Why was my PNG saved as a JPG?

JPG files can be much smaller than PNG files for photos, so Auto output uses JPG. Choose PNG under Advanced options if you need it, but it may produce a larger file and may not meet a very small target.

Free tool

Resize Image to KB

Resize an image to KB

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