WebM to SLN Converter
Extract WebM audio as Asterisk PBX signed linear online
Web Video to VoIP
Extract WebM audio and encode it as SLN — ready for use as hold music, prompts, and announcements on Asterisk phone systems.
Server-Based Work
All processing runs remotely. No Asterisk CLI tools or WebM decoders needed on your machine — just a browser and your file.
Fast Results
Audio extraction and SLN encoding are fast. Most WebM files produce a download-ready SLN telephony file in under a minute.
How to convert WEBM to SLN
Select files from Computer, Google Drive, Dropbox, URL or by dragging it on the page.
Choose sln or any other format you need as a result (more than 200 formats supported)
Let the file convert and you can download your sln file right afterwards
About formats
Frequently Asked Questions
SLN is the raw audio format for Asterisk PBX. WebM web video audio can be extracted and used for VoIP prompts, hold music, or greetings.
SLN is 8kHz, 16-bit signed integer, little-endian raw PCM — the native telephony format for Asterisk open-source PBX platforms.
WebM Opus or Vorbis audio is decoded and downsampled to 8kHz SLN. Speech content sounds clear on phone systems at this rate.
SLN is tailored for Asterisk PBX. While SOX can process it, the format mainly serves VoIP telephony environments.
Yes — upload WebM, select SLN, download. Audio decoding, downsampling, and SLN encoding all happen on our servers automatically.