Compress ICO to 20KB
Compress files to 20KB directly in your browser with no upload required.
Select ICO files
or drop files here
Maximum file size: 50MB per file
100% Secure
All processing happens in your browser. Your files never leave your device.
Super Fast
Process multiple files in seconds with our optimized browser-based tools.
High Quality
Keep your files clear and usable while reducing size or converting formats.
Compress, convert & crop images offline on iPhone - privacy-first, batch up to 200
Related Tools
Compressing ICO to Under 20 KB
The 20 KB target keeps a minimal favicon — often a single 16×16 layer, optionally 32×32 — for the smallest possible valid ICO. This suits tiny favicons where broad compatibility matters more than high-resolution variants. At these dimensions, simple shapes and limited palettes compress best. The result works in browser tabs and legacy contexts. For modern high-DPI tiles, consider shipping a separate PNG alongside this lean ICO.
How to Use This Tool
-
1
Select Your Files
Click the upload button or drag and drop your files into the upload area. You can select multiple files at once.
-
2
Start Processing
Choose the settings you need, then start the tool. Processing happens in your browser and results appear in real time.
-
3
Download the Results
Download your processed files individually or all at once when the task is complete. Your original files remain unchanged.
Frequently Asked Questions
Is a 16×16 only favicon enough?
For browser tabs, yes. Modern high-DPI displays benefit from a 32 px layer or a separate PNG favicon alongside the ICO.
Why is my ICO so small now?
We removed all but the essential small resolutions. ICO size is driven by how many resolutions and colors each layer stores.
Why Choose Let Compress?
- No file upload required - 100% client-side processing
- Free to use with no registration needed
- Batch compress multiple files at once
- Optimized compression algorithms for best results
- Works on all modern browsers and devices
- No file size limits or compression quotas
Learn More About Image Compression
Explore these authoritative resources to deepen your understanding of image compression and optimization.
MDN Web Docs: Image Optimization
Comprehensive guide on image optimization for web performance by Mozilla.
Google Web Fundamentals: Image Optimization
Best practices for image optimization from Google's web performance team.
W3C WebP Specification
Official W3C specification for the WebP image format.