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Resize an image by size or by KB

Set the width and height in pixels, cm, mm or inches, and optionally a maximum file size in KB. Useful for photos and signatures that an online form asks you to upload.

1. Add an image

2. New size

Units
px
px

3. File size and format

Maximum file size
Format

Add an image to resize it.

Check the size and file limits in your form's instructions before uploading.

How to resize an image

  1. Add your image

    Choose one JPG, PNG, WebP or HEIC (iPhone) image, up to 25 MB and 50 megapixels.

  2. Choose how to size it

    Pick Pixels, cm, mm or inches and enter the width and height. Keep proportions is on by default, so changing one side updates the other.

  3. Set a print resolution if you use cm, mm or inches

    The DPI choice (100, 150, 200 by default, or 300) appears only for cm, mm and inches. The tool converts your size to pixels at that resolution.

  4. Add a maximum file size if you need one

    Choose 20 KB, 50 KB, 100 KB or 200 KB, or enter your own number of KB (5 to 5000). Leave it on Any if only the dimensions matter.

  5. Check the result and download

    The tool shows the final size in KB and pixels. If you unlocked proportions, use Crop & position to adjust what is kept, then download the file.

What you can do with this tool

  • Pixels, cm, mm or inches

    Enter the width and height in whichever unit your form uses. For cm, mm and inches you pick the print resolution (100, 150, 200 or 300 DPI), and that DPI is written into the JPG file.

  • Optional maximum file size

    Pick 20, 50, 100 or 200 KB, or type a custom value from 5 to 5000 KB. JPG quality is lowered step by step until the file fits, and the exact final size is shown. 1 KB is counted as 1,000 bytes, so the file passes whether a site counts 1,000 or 1,024.

  • Cropped, never stretched

    If you unlock proportions and the new shape differs from your photo, the photo is cropped, centred by default. Use Crop & position to move it. It is never stretched.

  • Honest about what it cannot reach

    If the target is too small to reach at an acceptable quality, the pixel size is reduced, unless you fixed exact pixel dimensions. In that case the tool tells you it cannot reach the target.

  • JPG or PNG output

    JPG is the default. A KB target always gives a JPG, and transparent areas of a PNG become white.

  • Location data not included

    The output is re-encoded, so EXIF data such as GPS location is not carried over.

  • Stays on your device

    Everything runs in your browser. Your image is not uploaded, there is no sign-up, no watermark, and the tool is free.

Limits and output details

Accepted imagesJPG, PNG, WebP and HEICOne image, up to 25 MB and 50 megapixels
Size unitsPixels, cm, mm or inches
Print resolution100, 150, 200 (default) or 300 DPIUsed for cm, mm and inches
Largest output8000 px per side
Maximum file sizeOptional: Any, 20, 50, 100, 200 KB or customCustom: 5 to 5000 KB. 1 KB is counted as 1,000 bytes, so the file also passes sites that count 1,024
Output formatJPG (default) or PNGA KB target always produces a JPG
Output file nameresized-<width>x<height>.jpgOn the signature page: signature-<width>x<height>.jpg

Frequently asked questions

How do I resize an image to a specific size in KB?

Add your image, then choose a maximum file size: 20, 50, 100 or 200 KB, or a custom value. The tool lowers the JPG quality step by step until the file fits and shows the final size in KB.

Can I set the size in cm or mm?

Yes. Choose cm, mm or inches and enter the width and height. They are converted to pixels at the print resolution you pick (100, 150, 200 or 300 DPI), and that DPI is saved in the JPG so it prints at that size.

Why was my upload rejected even though the file is under the KB limit?

Forms often check the pixel size or the file format as well as the KB. Read your form's notice for the required dimensions and format, set them here, and add the KB limit too. This tool shows the final size in both KB and pixels so you can compare.

Will the picture be stretched?

No. With Keep proportions on, the shape stays the same. If you unlock it and choose a different shape, the photo is cropped, centred by default, and you can move the crop with Crop & position.

What if my form needs a minimum file size?

The tool does not pad files to make them bigger. It shows the size it produces, and if you need more KB you can raise the pixel dimensions or allow a larger maximum.

Can I choose PNG instead of JPG?

Yes, when you are not setting a KB target. A KB target always produces a JPG, and any transparent parts of a PNG become white.

Will the quality drop?

Making an image smaller in pixels or KB removes detail. When you set a KB limit the tool uses the highest JPG quality that still fits and shows the result, so you can judge it before downloading.

Does this tool know my exam's photo size?

No. Required sizes differ by exam and change from year to year, so check the size in your form's notice and enter it here. This tool does not state any exam's requirements.

Is my image uploaded anywhere?

No. The image is resized in your browser and is not uploaded. There is no sign-up and no watermark. The saved file has no location data and is named resized-<width>x<height>.jpg rather than using your original file name.

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