What’s the most common audio file format for a podcast? Afteranalyzing the file formatsof podcast episodes that were released between June 7-17, the team at the podcast player Castro concludes the winner, hands down, is MP3. Of the podcasts Castro looked at, 84.4% were MP3 files. Nearly one-in-ten were M4A files—they made up 9.4% of the sample. And 6.2% were MP4 files. When Castro released a similar analysis last October, MP3s had a similar 86.5% share of the market.

“Our advice is to use MP3, and that recommendation will probably never change,” Castro tells podcasters. It says it doesn’t have a “strong preference” between MP3 and M4A, however. But it says podcasters should avoid using “obscure formats” because “it increases complexity for players for no benefit.”