Airfoil Alternatives for Windows
Airfoil is not available for Windows but there are some alternatives that runs on Windows with similar functionality. The most popular Windows alternative is 
Stream What You Hear, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 10 alternatives to Airfoil and ten of them are available for Windows so hopefully you can find a suitable replacement. Other interesting Windows alternatives to Airfoil are 
WiFi Audio Wireless Speaker (Free), 
TuneBlade (Freemium), 
SoundWire (Freemium) and 
AirParrot (Paid).
- Stream What You Hear (SWYH) is a Windows application to broadcast the sound of your computer (ie: “what you hear”) on an UPnP/DLNA device such as TVs, amps, network receivers... View 14 alternatives to Stream What You Hear
- Free • Open Source
- Windows
Stream What You Hear vs Airfoil
Won't stream to airplay devices - Utility for turning your Android smartphone or tablet into a wireless speaker. View 11 alternatives to WiFi Audio Wireless Speaker
- TuneBlade - Stream audio to Airport Express, Apple TV, AirPlay compatible speakers and HiFi Receivers. Free version limitation: streaming stops every 10 minutes. View 7 alternatives to TuneBlade
- SoundWire lets you send any music or audio ("what you hear now") from your Windows or Linux PC to your Android mobile devices. View 11 alternatives to SoundWire
- Freemium • Proprietary
- Windows
- Linux
- Android
- Raspberry Pi
- AirPlay mirror your Mac or PC's screen to your Apple TV, wirelessly. Features 1080p Mirroring. View 20 alternatives to AirParrot
- Acoustic Bridge gives you the power to redirect audio from one PC to the speakers of another PC. View 9 alternatives to Stardock Acoustic Bridge
- Use your phone as a wireless speaker. Easily listen to music, movies or games wirelessly from your device. View 5 alternatives to AudioRelay
- This is a Java application to use the speaker connected to other computer on the network. It transfers audio in uncompressed PCM format and uses 172 kilobyte per second bandwidth. View 8 alternatives to SpeakerShare
Discontinued
The official website is no longer available. Last version, 1.0, released in January 2014, can be still downloaded from Softpedia.
- Free • Proprietary
- Mac
- Windows
- Linux
- AirMyPC allows you to wirelessly AirPlay mirror your Windows PC screen and sound to your TV through 2nd/3rd AppleTV. View 13 alternatives to AirMyPC
- Share Speaker Player is an outstanding yet easy-to-use application to share speaker in LAN with high quality. View 8 alternatives to Share Speaker Player
Discontinued
The official website is no longer available. Last version, 1.10, released in August 2009, can be still downloaded from Wayback Machine
- Free • Proprietary
- Windows