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Resize Image Online

Reduce an image's file size or pixel dimensions using the available resize modes. Choose an automatic balanced reduction, work toward a file-size limit, or set width and height when exact dimensions matter.

or drop one image here

One JPG or PNG up to 25 MiB
View limits & supported files
Supported input
Select a JPG or PNG image
Limits
One JPG or PNG up to 25 MiB
Additional limits
Target from 5 KB to 5,000 KB
Processing
No file upload
File handling
Files remain in your browser
Browser processing No account required Direct download
Practical guidance

Resize image dimensions or reduce file size

Use the resize mode that matches the real requirement. A target file size and a target pixel dimension are different goals, so choose the control that corresponds to the destination's rules.

Use Smart Reduce for a balanced smaller copy

Let the tool choose a practical reduction when you need a smaller image without specifying an exact KB value or pixel size.

Work toward a target file-size limit

Use Target KB when an upload portal or form sets a maximum file size. A successful result stays at or below the target and shows the actual output size.

Set width and height when dimensions matter

Choose explicit pixel dimensions when the destination requires a particular width or height rather than only a smaller file.

About this tool

Choose the resize method that matches the requirement

Image Resizer provides different controls for different constraints. Use file-size reduction for upload limits and dimension controls when the destination specifies pixels.

Useful for

  • Prepare images for forms, portals, websites, or email limits.
  • Reduce oversized screenshots or camera photos before document conversion.
  • Create a separate resized copy while keeping the original available.

Good to know

  • JPG/JPEG and PNG inputs are supported. Target KB and Width & Height create JPEG output; Smart Reduce can return the untouched source when re-encoding would not make it smaller.
  • Target KB treats the value as a maximum and does not promise an exact byte count.
  • Do not enlarge a small source image and imply that new detail has been created.

How to Resize an Image

Choose the source image, select the resize mode that matches your requirement, review the output, and download the resized copy.

  1. Choose a supported image.
  2. Select Smart Reduce, Target KB, or Width & Height according to the job.
  3. Enter any required file-size or dimension values.
  4. Create the resized image and review its actual file size and dimensions.
  5. Download the result and keep the original source if it may be needed later.
How to Resize an Image

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Need to place several images into a document? Convert JPG or PNG to PDF.

Image size questions

Can I resize an image to a target KB size?

Yes. A successful Target KB result is at or below the requested value, but an exact byte count is not guaranteed.

Can I resize by width and height?

Yes. Enter explicit pixel dimensions, optionally keep the aspect ratio locked, and choose whether smaller images may be enlarged.

What does Smart Reduce do?

Smart Reduce keeps the decoded dimensions, tries balanced JPEG encoding, and returns the untouched source file when re-encoding would not make it smaller.

What format is the resized image?

Target KB and Width & Height create JPEG files. Smart Reduce may return the untouched original file, including PNG, when re-encoding would not make it smaller.

Will resizing reduce image quality?

Reducing dimensions or re-encoding an image can change visible quality. The amount depends on the resize mode and source image.

Are my images uploaded to PDFKaka?

No. Selected image contents are processed locally in this browser.

Practical PDF guides for complete tasks

Image Resizer guide How to Resize an Image to a Required KB Limit Set required pixel dimensions first when the destination specifies them. Read guide → Image Resizer guide How Image Dimensions, DPI, and File Size Work Together Understand how pixel dimensions, DPI, and encoding affect image size so you can choose the right width, height, and KB target. Read guide → Image Resizer guide How to Reduce Image Size Without Excess Blur Remove unnecessary pixels first and use the highest JPEG quality that still meets the required maximum size. Read guide →
View all PDFKaka Guides →