Audio Joiner

Online Audio Joiner is designed to merge several songs (mp3, m4a, wav, etc) into a single track. The program is absolutely free and operates online; therefore you don’t need to install it on your computer. Just open the browser and start merging. Features: Seamless Merging Cross-fade Support of Most Audio and Video Formats User-Friendly Interface Interval Adjustment Merge Unlimited Number of Songs

Screenshots from Chrome Web Store