Image Compressor & Resizer

TOOLS

QUBU / IMAGE TOOLS

Lighter images. The right dimensions.

Compress, resize and try a target file size. Your files stay on this device.

Private by design · Processed on this device

Drop images here

Up to 20 files · 20 MB each · 16 megapixels

Choose images

Static images only. Animated files are not flattened silently.

Output settingsFormat

Quality 90%

PNG is lossless; the quality slider does not reduce PNG file size.

Maximum width (px)

Maximum height (px)

Keep aspect ratio; do not upscale

With the ratio lock off, dimensions are applied exactly and may stretch the image. A blank field keeps its original dimension.

Target file size (optional)

1 KB = 1024 bytes. The target is attempted by reducing quality, without further resizing. PNG has no quality setting.

Dimensions follow your chosen limits. Metadata is removed; the browser may change colours.

Keep image dimensions and file sizes under control

Prepare screenshots for upload limits, give product images a consistent width or reduce the weight of a game page's cover images. The tool reads static JPG, PNG, WebP and supported AVIF files. Output formats are tested in your browser. Your images are never uploaded to a server.

How to use it

Select up to 20 images, each within 20 MB, 16 megapixels and 8192 pixels per side.
Choose a format and quality. Use PNG or WebP for transparency, or JPEG for opaque photographs.
Optionally enter maximum width and height. With aspect ratio locked, the image fits inside that box without cropping or upscaling.
Optionally set a KB/MB target. Check the preview and actual file size, then download individual images or a ZIP.

Example: a game page cover

For a 2400 × 1600 cover, setting width to 1200 and leaving height blank produces 1200 × 800 pixels. Start with WebP at 85% quality. A 200 KB target lets the tool try lower quality settings when needed. There is no guarantee that your image will fit: inspect small lettering and sharp edges in the downloaded result.

How the target works

The browser re-encodes the image on a canvas, first at your selected quality. If it exceeds your target, it tries up to eight more quality levels down to 10%. The first tested result that fits is returned. If none fits, you get the smallest tested result with a clear warning. This is a bounded search, not a claim to find the best possible quality. The tool never secretly reduces dimensions to meet the target. Here, 1 KB means 1024 bytes and 1 MB means 1,048,576 bytes.

Why did my PNG not get smaller?

PNG encoding is lossless and ignores the quality slider. Re-encoding can increase file size. Reduce pixel dimensions or choose WebP when appropriate. This tool does not reduce the colour palette or guarantee a smaller file.

Limits and privacy

File signatures and pixel limits are checked before processing; actual output format and dimensions are checked afterwards. Animated files and tiled AVIF images are not supported. Metadata is removed and colour profile conversion can change colours. JPEG replaces transparency with your chosen background. Batch output is limited to 100 MB; large images can take time on phones. Clear files releases previews and results from memory.

Frequently asked questions

Are my images stored on a server?

No. Conversion, resizing and ZIP generation happen in your browser.

What happens when I unlock the aspect ratio?

Entered dimensions are applied exactly. This can stretch or upscale the image; a blank dimension keeps its original value.

What does the quality percentage mean?

It is an encoder setting, not the percentage of detail retained. With a target it is the upper limit. Different browsers may produce different file sizes.

Related tool

For a format change without resizing, use the Image Converter. Explore the other production helpers in QUBU Tools.