トピック、リスナー層、広告量に応じた推奨エピソード時間を算出。任意のビットレートでのMP3／AACファイルサイズも正確に見積もります。
| Duration | MP3 (kbps) | File size |
|---|
Recommended length blends two signals: (1) typical format duration from Edison/Spotify research, and (2) audience listening context (commute averages 27 min, workouts 38 min, deep listens 75+ min).
File size = bitrate × duration. 128 kbps × 60 min = 128/8 × 3600 ≈ 57.6 MB. Most directories cap at 500 MB per file.
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