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IMAGES & MEDIA

Image Compressor

Reduce image file sizes for JPG, PNG, WebP, GIF, and BMP formats. Set quality percentage or a target size limit in KB, resize dimensions in pixels, and inspect original vs compressed previews with a split slider before downloading.

Tool statusUses server processing
Preview
This tool is processed on the server.

Your images are sent to the backend, re-encoded at the settings you chose, and deleted right after processing.

prontouso://images/image-compressor
JPG · PNG · WEBP · GIF · BMPPILLOW SERVER
Or drop imageschoose a file
.png, .jpg, .jpeg, .webp, .gif, .bmp · up to 20.0 MB. Sent to our server to process, then deleted right away.

How it works

  1. Enter your input

    Fill in the values, paste your text, or upload the file this tool works with.

  2. See results instantly

    Most tools update live as you type; a few use a single button. Either way, the result appears right on this page.

  3. Use your results

    Copy, download, or share what the tool produces — you're always in control of the output.

Secure in-memory processing on our server — To deliver advanced image compression without browser limitations, images are transmitted over an encrypted connection to a ProntoUso server, re-encoded strictly in memory for the request, and immediately discarded. No files are written to disk or stored after processing.

What is Image Compressor?

ProntoUso's Image Compressor reduces JPG, PNG, WebP, GIF, and BMP file sizes by adjusting compression levels, KB target size caps, or resolution limits. Processing happens securely in server memory using real image encoding.

UNDERSTAND THE TOOL

How to balance quality, KB target size, and color palette

Learn how file size reduction works for JPG, PNG, WebP, and GIF images, balancing visual fidelity, file size caps, and output formats.

Quality Mode vs. Target KB Size Mode

In Quality mode (10 to 100), you manually set the encoding level: lower numbers create smaller files but may introduce visual artifacts on photos. In Target Size mode (KB), the server performs a binary search to find the highest quality setting that stays within your requested KB cap — ideal for form uploads with strict file size limits.

How compression affects JPG, PNG, and WebP differently

For lossy formats like JPG and WebP, compression discards high-frequency detail and subtle color variations that human eyes rarely detect. For PNG — which is strictly lossless at the pixel level —, size reduction is achieved via color palette quantization. Quality 100 retains all original colors, while lower settings compress the palette for smaller files.

Compression profiles and optional resizing

The Balanced profile fits most images. Smaller File enables chroma subsampling on JPGs and reduced palettes on PNGs. Best Quality prioritizes color fidelity and lossless encoding for smaller images. If your original image has an excessively high resolution, enable the optional Resize toggle to set max width or height limits before compressing.

Interactive before-and-after comparison and batch zip

After compression, use the interactive split-slider comparator to inspect image details side-by-side. When uploading multiple images at once, the tool processes the batch in a queue and allows downloading items individually or packaged together in a ZIP file.

How to use it

  • Drop one or more images (JPG, PNG, WebP, GIF, or BMP) into the dropzone.
  • Select compression mode (Quality or Target Size in KB) and choose your preferred profile.
  • Optionally enable resizing to set maximum width and height dimensions.
  • Click Compress, inspect the visual before/after comparison, and download individual files or the batch ZIP.

Secure in-memory processing on our server

To deliver advanced image compression without browser limitations, images are transmitted over an encrypted connection to a ProntoUso server, re-encoded strictly in memory for the request, and immediately discarded. No files are written to disk or stored after processing.

Frequently Asked Questions

What is the difference between Quality mode and Target KB Size mode?

Quality mode uses a fixed percentage slider (10 to 100). Target KB Size mode lets you specify a maximum file size cap in KB, and the tool automatically determines the highest quality level that fits within that size.

Why does PNG compression modify the color palette?

Because the PNG format does not support direct lossy pixel compression like JPG, file size reduction is achieved by reducing the number of distinct colors in its palette. A quality of 100 keeps 100% of original colors, while lower values optimize the palette while preserving edge sharpness.

What happens if the target KB size is lower than physically possible?

If the image cannot fit into the requested KB limit even at the lowest acceptable quality, the tool delivers the smallest feasible file and displays an informative warning, preventing unreadable image degradation.

Does image compression change width and height dimensions?

No. Standard compression reduces file size in bytes while keeping pixel dimensions unchanged. If you want to alter width and height, turn on the optional Resize toggle before compressing.

Can I compress multiple images at once and download a ZIP?

Yes. The tool supports batch uploads. Once batch processing is complete, you can review each file and download all compressed images bundled together in a single ZIP file.

Are uploaded images stored on ProntoUso servers?

No. Processing occurs exclusively in server RAM during transmission. As soon as the compressed file is delivered back to your browser, temporary in-memory data is erased.

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