Reduce Image Size in KB

Free and unlimited: set a maximum edge and a file-size budget. This tool reduces unnecessary pixels before compressing your image.

Free & unlimitedNo signupNo daily caps
Image compressor

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JPG, PNG & WebP · Up to 20 files · 30MB each
Output settings

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TOOL GUIDE

Reduce oversized images by choosing both dimensions and bytes

How to use this tool

  1. Choose your image.
  2. Set a maximum edge in pixels and the target KB.
  3. Reduce, review the new dimensions, and download.

Two limits, one workflow

Pixel dimensions control the amount of visual information. File size controls storage and upload limits. Lowering dimensions first can give better results than heavily compressing a full-resolution original.

When to reduce dimensions before compression

Use this workflow when a source image contains substantially more resolution than its destination needs. A full camera photo may be thousands of pixels across even when a form or thumbnail uses only a small version. Removing unnecessary pixels first gives the encoder less information to fit within the requested file allowance.

The output is a JPEG. If your source PNG or WebP has transparency, that transparent area becomes white. Choose the mixed-format compressor instead when you need to preserve an alpha channel or compare other output formats.

Tools for this step: Mixed-format image compression

Example: a 2,400-pixel photo for a smaller upload

Consider a 2,400 × 1,800 landscape photograph. With a maximum edge of 800 pixels, the proportional resize creates an 800 × 600 image before target-driven compression. That leaves one ninth of the original pixel count. It does not guarantee one ninth of the original bytes, because the new image still needs to be encoded.

Now enter the actual file-size ceiling from the destination. If that JPEG still exceeds the allowance, the tool can lower quality and reduce dimensions again. Check the final width and height, since the initial 800-pixel setting is a ceiling rather than a guaranteed minimum.

Set the maximum edge and target independently

Maximum edge is measured in pixels. Target size is measured in decimal KB, where one KB is 1,000 bytes. These settings answer separate questions: how large the image may be in dimensions, and how large its encoded file may be in storage. A useful result needs both to suit the destination.

Quality affects the JPEG encoding. A higher setting generally retains more detail, but it can require more bytes. Start with the intended pixel dimensions and a moderate quality level, inspect the result, and adjust only if the file misses its requirement or important detail looks damaged.

The reducer’s three main controls
ControlUnitEffect
Maximum edgePixelsLimits the longest side proportionally
Target sizeDecimal KBSets a ceiling for the attempted output bytes
QualityEncoder settingControls the JPEG quality search

Why a smaller file might still be rejected

Upload forms can enforce dimensions, file extension, orientation, or content rules in addition to bytes. Read the result measurements and compare them with the complete instructions. An image meeting a KB cap can still be too narrow or too short, and this tool cannot certify application-photo requirements.

If the result has too few pixels, try a closer crop of the useful content or an allowance that permits more detail. Repeatedly recompressing the already-reduced download will not restore the source. Keep the original and make new attempts from it.

Tools for this step: Crop unnecessary background · Set exact output dimensions

Frequently asked questions

Is this tool free and unlimited?

Yes. It is free to use with no signup and no daily usage caps. You can process up to 20 files of up to 30MB each in one batch, then download your results.

Is this the same as resizing to an exact width and height?

No. This tool limits the longest edge and then works toward a byte target. It may reduce dimensions further. Use the dedicated resizer when a specific canvas is the primary requirement.

Can I enter a custom target instead of choosing a preset?

Yes. Enter the receiving service’s limit in the target-size field. The output is measured against that value; the tool does not create a new public webpage or change the canonical URL for custom settings.

Why does the result have a white background?

The reducer exports JPEG, which does not support transparency. Transparent source pixels are blended onto white. Use a PNG or WebP output in the mixed-format compressor if transparency must survive.

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