AscendLab
Tool guide

Image Compressor Guide

Reference for reducing image file size with browser-side processing, including supported formats, quality controls, transparency limits, and common errors.

Quick answer

Upload an image, choose the output format and quality level, preview the size change, then download the compressed result.

What this tool does

The image compressor reduces file size by re-encoding an image in the browser. It helps prepare screenshots, photos, documentation images, and web assets for faster sharing or publishing.

Supported input

  • Common browser-decodable image formats such as PNG, JPEG, and WebP
  • Screenshots, photos, UI exports, and simple graphics
  • Files that fit comfortably in browser memory

Output

  • Downloadable compressed image
  • File size comparison
  • Format and quality-dependent result

Step-by-step use

  1. Select an image file.
  2. Review the original size and dimensions.
  3. Choose an output format.
  4. Adjust quality and preview the result.
  5. Compare original and output size.
  6. Download the compressed image.

Data handling and processing behavior

Processing is handled in the browser for this tool based on the current public implementation. Avoid entering sensitive images unless you have reviewed the implementation.

Limits

  • PNG compression may not reduce size much for some images.
  • JPEG does not preserve transparency.
  • Canvas-based processing may change metadata or color profile details.
  • Very large images may slow mobile browsers or low-memory devices.

Common errors

The output is larger

Some PNGs and flat graphics are already efficient. Try another format or resize the image first.

Transparency disappeared

The image was likely exported to JPEG. Use PNG or WebP when transparency matters.

Text looks fuzzy

The quality value may be too low or the image was resized too aggressively.

Next steps

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