Audio streaming software for internet radio and 24/7 live audio.

It depends on which job you are hiring it for. Radio automation tools assemble your program on a computer, and encoders like OBS turn that program into a stream. Castr is the delivery layer: audio streaming software in the cloud that takes the stream and handles ingest, playback on your website, recording, and distribution to every platform. For internet radio and live shows, a free encoder plus Castr covers the whole chain.

Audio streaming means sending sound over the internet so listeners play it in real time instead of downloading a file. Live audio streaming covers radio stations, talk shows, DJ sets, and event feeds. Castr ingests the live feed from your encoder and delivers it to listeners as an HLS stream over multiple CDNs.

Connect an encoder that outputs RTMP or SRT to Castr and leave it running, since streams have no time limit on any plan. For a channel that mixes prepared shows with live segments, schedule everything into one rundown with 24/7 cloud playout. Shows upload as MP4 files, so wrap the audio with a static image or visualizer. The practical limit is your plan's monthly bandwidth, which starts at 200 GB on Starter.

Much less than video, which is what makes audio cheap to run. At 128 kbps, one listener-hour is roughly 58 MB, so Starter's 200 GB of monthly bandwidth covers about 3,400 listener-hours a month. A video stream at even 2.5 Mbps burns bandwidth nearly 20 times faster. Use the bandwidth calculator on this site to size a plan for your bitrate and audience.

Free audio software for streaming exists on the encoding side: OBS is free and sends RTMP straight to Castr. Delivery is where free tools fall short, because listener bandwidth costs real money and free tiers cap or brand it. Castr plans start at $19.99 per month, with a 7-day trial and no credit card required.

No. Audio-only broadcasts are a supported workflow. Send your feed from any RTMP or SRT encoder, embed the player on your website, and use the same recording, scheduling, access controls, and multistreaming the video platform provides. One caveat: audio-only streams play fine in the Castr player, but YouTube, Facebook, and Twitch reject them, so add a static image or visualizer as the video track in your encoder before simulcasting to social platforms.

Radio automation software like SAM Broadcaster or RadioBOSS builds your program: playlists, rotation, jingles. Castr is audio broadcasting software for the other half. It takes the finished program from your encoder and delivers it to your website and streaming platforms. Many stations run both, and stations that program from uploaded files can let Castr's cloud playout handle the scheduling too. Each show uploads as an MP4 with a static image or visualizer as the video track.

No. Castr ingests RTMP and SRT and delivers HLS, so it replaces an Icecast or Shoutcast server rather than hosting one. If your current tool only outputs Icecast, use an encoder with RTMP output, such as OBS, to send the same program to Castr.

Yes. Password protection is on every plan, and domain and geographic controls are on Premium and higher. To charge for access, put the stream behind the built-in paywall on any plan, or run in-stream advertising on Standard and higher.

Yes. Every plan includes an HTML5 player you embed with a snippet, so listeners tune in on your own page. Premium and higher plans also provide an HLS URL to feed your own player or apps.

No. Castr does not generate RSS feeds or distribute episodes to podcast directories like Apple Podcasts or Spotify. It is live audio broadcast software plus on-demand hosting: you stream shows live, record them, and host replays on your own website. Many stations pair Castr for the live channel with a dedicated podcast host for the RSS side.

Yes. Castr offers a 7-day Starter trial with no credit card required. Advanced workflows and higher limits may require a paid tier or a technical consultation.