Skip to content

How to reduce an image's file size (to 50 KB, 100 KB or less)

By the Fusion Office team · Updated

Quick answer

Open Compress image, choose File size, type the limit (for example 50 KB) and press Compress. The image is saved at the highest quality that fits. For exact dimensions too, such as a 3.5 × 4.5 cm photo, use Resize image with its file-size limit.

Fit an image under a size limit

  1. 1Open Compress image and choose one or more images.
  2. 2Select Compress by File size and enter the limit, such as 20 KB, 50 KB or 100 KB (you can also write 1.5 MB).
  3. 3Keep the format, or choose JPG for photos.
  4. 4Press Compress and check the new size shown for each image, then download.

Compress or resize?

Compressing lowers the quality of the stored image; resizing lowers its dimensions in pixels. Small targets usually need both: a 12-megapixel phone photo can't become a 20 KB file at full size without looking terrible, but at 600 pixels wide it can look fine.

Forms for exams, jobs and government services often specify both dimensions and size, for example a 3.5 × 4.5 cm photo under 50 KB, or a signature of 140 × 60 pixels under 20 KB. Resize image handles both at once: set the size in pixels or cm (with presets for passport photos and signatures), turn on Limit the file size, and enter the KB limit.

Pick the right format

  • JPG: photos and scanned signatures. Smallest for photographs.
  • PNG: screenshots, logos and graphics with sharp edges or transparency. Usually larger for photos.
  • WEBP: smaller than both for most images, but some older forms don't accept it.

If a form rejects your file type, Convert image changes it to JPG, PNG or WEBP, including iPhone HEIC photos. Crop away unneeded background first with Crop image: fewer pixels means a smaller file.