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Compress Images to a Target Size

Automatically fit photos under 100KB, 200KB, 500KB, 1MB, or your own file size limit

Drop images here or choose files

JPG, PNG, WebP. Up to 20 images, 20MiB per file, 100MiB total, and 40 megapixels per image.

1KB = 1,000 bytes; 1MB = 1,000KB. Enter a custom limit from 1 to 10,000KB.

Dimensions are reduced if quality changes alone cannot meet the limit. PNG is resized to reduce file size.

What this tool does

Meet a specific upload size limit without guessing which quality setting to use. This free online tool measures the actual bytes of each encoded JPG, PNG or WebP image and adjusts quality, then dimensions if needed, until it fits under 100KB, 200KB, 500KB, 1MB or a custom limit. Compare the original photo with the output and download one image or the successful batch as a ZIP. All image processing stays in your browser.

Common use cases

  • Fit a profile photo under an application form’s maximum file size.
  • Prepare a batch of product photos for a marketplace with an upload cap.
  • Reduce email attachments and inspect how much detail remains before sharing.

How to use it

  1. Choose JPG, PNG or WebP files, or drop them into the file area.
  2. Select a preset or enter a custom KB limit, then choose the output format.
  3. Select Compress to This Size and compare the original and output dimensions, size and appearance.
  4. Download individual results or save all successfully compressed images in a ZIP.

Input and output example

Input: A photo with a target size of 500KB and JPG output
Output: A successful result is a JPG no larger than 500,000 bytes. The exact size and dimensions depend on the source image.

Important notes

  • KB uses decimal units: 100KB is 100,000 bytes and 1MB is 1,000,000 bytes. Pixel dimensions are a separate requirement.
  • Lossy JPG and WebP output can lose detail. Dimensions are reduced when quality adjustments alone cannot meet the limit. PNG uses resizing to reduce file size.
  • JPG replaces transparent areas with white. Choose PNG or WebP to keep transparency.
  • Up to 20 files, 20MiB per file and 100MiB total. Each image must be at most 40 megapixels and 16,384px on each side. HEIC, GIF, SVG and animated WebP are not supported. PNG output is also a still image.
  • Check the destination’s dimensions, accepted formats and photo rules separately from the file size.

Frequently asked questions

How do I compress a photo to 100KB?
Choose your image, select 100KB and compress. A successful output contains at most 100,000 bytes. Review the preview because a small limit may require lower quality or smaller dimensions.
Does compression change the image dimensions?
JPG and WebP start with quality adjustments. If those cannot meet the limit, the tool reduces dimensions. PNG is resized to reduce file size. Aspect ratio is preserved apart from integer-pixel rounding.
Are my photos uploaded?
No. Reading images, compression, preview and ZIP creation happen locally in your browser.
Why is the output larger than the original?
Changing formats or re-encoding an already small image can increase its size. The comparison shows both file sizes and reports a size increase when that happens.
Can I download all compressed images at once?
Yes. Up to 20 images are processed sequentially. The ZIP contains successful outputs only, with numbered filenames to avoid collisions.