
Online Image Compressor by Compress Karu
Online Image Compressor is a powerful Firefox extension that allows you to easily compress images without sacrificing quality. Reduce file sizes for faster uploads, sharing, and storage while maintaining visual fidelity.
You'll need Firefox to use this extension
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About this extension
CompressKaru's Online Image Compressor brings professional image compression directly to your Firefox browser. This lightweight extension enables you to quickly reduce image file sizes while maintaining visual quality. Perfect for web developers, designers, photographers, and anyone who works with images regularly.
The extension features an elegant, user-friendly interface that makes image compression intuitive. Simply drag and drop your images, adjust compression settings to your needs, and download the optimized results. No technical knowledge required - just efficient image compression at your fingertips.
With customizable compression settings, you can balance quality and file size according to your specific needs. Whether you're optimizing images for websites, social media, or email, Online Image Compressor has you covered.
Features
✅Drag-and-drop interface: Simply drag images directly into the extension
✅Custom compression levels: Adjust quality settings from 0-100%
✅Resize images: Set maximum dimensions while maintaining aspect ratio
✅Multiple output formats: Save as JPEG, PNG, or WebP
✅EXIF data control: Option to preserve or remove metadata
✅Instant preview: See compression results before downloading
✅Context menu integration: Right-click on any image to compress it
✅Clipboard support: Copy compressed images directly to clipboard
✅Customizable defaults: Set your preferred compression settings
✅100% private: All processing happens locally in your browser
✅No file size limits: Compress images of any size
How to Compress an Image Size?
↳Basic Compression
➤ Click the extension icon in your Firefox toolbar
➤ Drag and drop an image into the compression area (or click "Choose File")
➤ Adjust the compression level using the slider
➤ Set maximum width if resizing is needed
➤ Click "Compress Image"
➤ Click "Download Image" to save the compressed result
↳ Context Menu Compression
➤ Right-click on any image on a webpage
➤ Select "Compress this image" from the context menu
➤ Adjust settings in the popup window
➤ Download or copy the compressed image
↳ Customizing Default Settings
➤ Right-click the extension icon
➤ Select "Options" or "Preferences"
➤ Set your preferred default compression level
➤ Choose default maximum width
➤ Select preferred output format
➤ Toggle EXIF data preservation
➤ Click "Save Settings"
FAQs
1️⃣. Does this extension upload my images to a server?
A: No. All compression happens locally in your browser – your images never leave your computer.
2️⃣. What image formats are supported?
A: The extension supports JPEG, PNG, GIF, WebP, and BMP formats.
3️⃣. Will compression reduce image quality?
A: Higher compression levels may reduce quality. Use the preview to find the perfect balance between size and quality.
4️⃣. Is there a file size limit?
A: No, you can compress images of any size, limited only by your browser's memory.
5️⃣. Can I compress multiple images at once?
A: Currently, the extension compresses one image at a time.
6️⃣. Does this work on mobile Firefox?
A: The extension is designed for desktop Firefox. Mobile support may be limited.
7️⃣. Will this extension slow down my browser?
A: The extension is lightweight and only active when you use it.
Visit https://compresskaru.com/ for more online image tools and resources.
The extension features an elegant, user-friendly interface that makes image compression intuitive. Simply drag and drop your images, adjust compression settings to your needs, and download the optimized results. No technical knowledge required - just efficient image compression at your fingertips.
With customizable compression settings, you can balance quality and file size according to your specific needs. Whether you're optimizing images for websites, social media, or email, Online Image Compressor has you covered.
Features
✅Drag-and-drop interface: Simply drag images directly into the extension
✅Custom compression levels: Adjust quality settings from 0-100%
✅Resize images: Set maximum dimensions while maintaining aspect ratio
✅Multiple output formats: Save as JPEG, PNG, or WebP
✅EXIF data control: Option to preserve or remove metadata
✅Instant preview: See compression results before downloading
✅Context menu integration: Right-click on any image to compress it
✅Clipboard support: Copy compressed images directly to clipboard
✅Customizable defaults: Set your preferred compression settings
✅100% private: All processing happens locally in your browser
✅No file size limits: Compress images of any size
How to Compress an Image Size?
↳Basic Compression
➤ Click the extension icon in your Firefox toolbar
➤ Drag and drop an image into the compression area (or click "Choose File")
➤ Adjust the compression level using the slider
➤ Set maximum width if resizing is needed
➤ Click "Compress Image"
➤ Click "Download Image" to save the compressed result
↳ Context Menu Compression
➤ Right-click on any image on a webpage
➤ Select "Compress this image" from the context menu
➤ Adjust settings in the popup window
➤ Download or copy the compressed image
↳ Customizing Default Settings
➤ Right-click the extension icon
➤ Select "Options" or "Preferences"
➤ Set your preferred default compression level
➤ Choose default maximum width
➤ Select preferred output format
➤ Toggle EXIF data preservation
➤ Click "Save Settings"
FAQs
1️⃣. Does this extension upload my images to a server?
A: No. All compression happens locally in your browser – your images never leave your computer.
2️⃣. What image formats are supported?
A: The extension supports JPEG, PNG, GIF, WebP, and BMP formats.
3️⃣. Will compression reduce image quality?
A: Higher compression levels may reduce quality. Use the preview to find the perfect balance between size and quality.
4️⃣. Is there a file size limit?
A: No, you can compress images of any size, limited only by your browser's memory.
5️⃣. Can I compress multiple images at once?
A: Currently, the extension compresses one image at a time.
6️⃣. Does this work on mobile Firefox?
A: The extension is designed for desktop Firefox. Mobile support may be limited.
7️⃣. Will this extension slow down my browser?
A: The extension is lightweight and only active when you use it.
Visit https://compresskaru.com/ for more online image tools and resources.
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Permissions and dataLearn more
Required permissions:
- Input data to the clipboard
- Download files and read and modify the browser’s download history
- Access your data for all websites
More information
- Add-on Links
- Version
- 1.3
- Size
- 232.7 KB
- Last updated
- 2 months ago (May 12, 2025)
- Related Categories
- License
- All Rights Reserved
- Version History
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