Tools / File Converter / ASF to M4R Converter

ASF to M4R Converter

Convert ASF files to M4R. Free, without uploading.

This tool converts ASF files to M4R. Advanced Systems Format.

M4R is the iPhone ringtone format (AAC audio inside). Ringtones can be up to 40 seconds. Only the audio of the ASF video is kept and saved as M4R; the picture is dropped. M4R is lossy; you choose the quality from 96 to 320 kbps. 192–256 kbps is enough for music, 128 kbps for speech.

Conversion runs on your device; your file is never sent to a server. The components download once on first use, and later conversions start right away.

How to use

1. Choose the ASF video, drag it in, or paste its link.
2. Choose the audio quality; optionally enter a start and end time.
3. Press "Convert" and download the M4R file.

Frequently asked questions

Will audio quality drop when converting to M4R?

M4R is lossy, so there is a small loss you won’t hear at higher bitrates. If the source is already lossy, a higher bitrate won’t improve it.

Is there a file size limit?

No fixed limit; your device’s memory decides. Computers usually handle files up to 1–2 GB.

Is my file uploaded?

No. Your ASF file is converted to M4R inside your browser.