View ACT Files Online

About ACT Files

An .act file is an audio file recorded by S1 MP3 players and other low-cost portable voice recorders, and saved in the Adaptive Differential Pulse-Code Modulation (ADPCM) compressed ACT format. These files typically store voice memos or short sound clips recorded through a built-in microphone at low bitrates, prioritizing small file sizes over sound fidelity. The format was commonly used in the early 2000s, when memory capacity on portable devices was limited, and efficient voice recording was more critical than high-quality audio playback.

ACT files are primarily found on legacy devices or removable flash memory used with older MP3 players. They can be transferred to a computer for playback, archiving, or conversion to more modern formats. The format is not widely supported by contemporary media players, but you can open and play .act files on FileHelper.com by dragging them to this page.

Converting ACT Files

You can convert .act files to other formats to improve compatibility or make sharing easier:

• Converting to MP3: Allows ACT recordings to play on nearly all media players and devices, though the conversion applies another round of lossy compression, slightly reducing clarity.
• Converting to AAC: Provides efficient compression and good playback quality on modern devices, especially smartphones and tablets, while maintaining relatively small file sizes.