Online CRN Converter & Compressor - Encode Images to CRN (Crunch)
Create crunchy textures using our free online CRN converter. Swiftly encode your assets to .crn container files relying on Crunch (BC1/BC3 DXT compressions) minimizing end distribution size.
Related Searches
Step 1: Select Image
Drag and drop an image here
or
- Requirement: width and height must be multiples of 4
HDR input note
HDR, EXR, and UltraHDR JPEG files can be used as inputs. Most current output paths still tone map into the RGBA8 encode pipeline; use DDS BC6H, KTX2 RGBA16F, or KTX2 RGBA32F when you need to preserve HDR source data as much as possible.
Features
Unity Crunch Compression
Powered by the Crunch compression algorithm, designed specifically for Unity game asset slimming and ultra-fast download distribution.
BC1 & BC3 (DXT1/DXT5) Modes
Full support for opaque BC1 (DXT1) and transparent BC3 (DXT5) textures, balancing exceptional compression ratios with GPU transcode speed.
Quality Control
Quality level 0-255 to balance visual quality and size.
Browser-side Processing
All encoding runs locally without uploading source images.
Unified Workflow
Same upload/status/download UX as other encode pages.
Round-trip Validation
Encoded files can be verified immediately in CRN decode page.
How to Use
Upload Image
Select PNG/JPG/WebP or other common image formats.
Choose Format
Select BC1 or BC3 based on your target use case.
Set Quality
Adjust quality level in the 0-255 range.
Download Result
Download the generated .crn file when encoding completes.
Frequently Asked Questions
CRN (.crn) is an advanced texture container created by the Crunch algorithm (originally developed by Rich Geldreich). Widely adopted in the Unity game engine and indie game development, CRN slashes texture disk footprint far beyond standard DDS files and unpacks directly into GPU-native DXT1/DXT5 (BC1/BC3) blocks in milliseconds.
CRN is optimal for indie games, Steam PC titles, and web/online game pipelines needing minimal install size and fast downloads. It reduces texture transfer sizes by 50%-70% over raw DDS while retaining high fidelity.
BC1/BC3 are 4x4 block-based formats, so non-4x dimensions are blocked in this first release.
Higher quality usually improves image fidelity, but may increase encode time and output size.
No. Encoding is performed locally in your browser via WebAssembly.
Yes. You can load the generated file in the CRN decode page for quick validation.