Always be aware of restrictions on how you can use any music that you download for free. There will be an End User License. Please make sure you read the fine print so that you know the limits and terms of the “free” download. Some sites expressly state that you cannot use the music for commercial purposes. You can get hit by unexpected fees and copyright infringement notices. Many of these companies make their money by placing ads on YouTube videos that have used their music.
Free Music (and Sound Effects):
A substantial number of music tracks and sound effects are available to download for free from this site. Commercial use of the music tracks is allowed. The site requires that you give credit to them for the use of their sounds and they may share your email address with other companies owned by their owner. The End User License and other site policies are well documented and easy to read.