Free online 3GP to AAC converter

Some phones and older messaging systems save recordings as 3GP, while audio editors, players, or publishing workflows may require a standalone AAC file. Converting extracts the audio track and, when necessary, re-encodes it as AAC.

What the 3GP format is

3GP is a multimedia container based on the ISO Base Media File Format, designed for mobile networks and phones with limited storage and bandwidth. Older Nokia, Sony Ericsson, Android, and feature-phone cameras commonly created .3gp recordings; messaging exports and archived mobile videos are also typical sources.

A 3GP file can contain video encoded with H.263, MPEG-4 Part 2, or H.264, together with audio encoded as AMR-NB, AMR-WB, or AAC. The filename does not identify the audio codec, so a 3GP file may already contain AAC or may require decoding and re-encoding from AMR.

What the AAC format is

AAC, or Advanced Audio Coding, is a lossy audio codec supported by phones, media players, web browsers, editing software, and broadcasting systems. At comparable bit rates, it generally provides better quality than older MP3 or AMR encoding, making it suitable for speech, music, and compact distribution files.

A standalone AAC file normally uses the ADTS container and the .aac extension. AAC stored in an MP4 or M4A container is packaged differently; use M4A when the receiving application requires metadata, cover art, or an MP4-family container.

How to convert the file with FFmpeg

FFmpeg is suitable for both extracting audio and converting AMR or other source codecs. Run the command in the folder containing the input file:

ffmpeg -i input.3gp -map 0:a:0 -vn -c:a aac -b:a 128k output.aac

-map 0:a:0 selects the first audio stream, -vn excludes video, -c:a aac selects the AAC encoder, and -b:a 128k sets the bitrate. Use about 64k to 96k for speech when file size matters, or 192k for music when higher quality is preferred.

Inspect the source before converting when avoiding an additional lossy encoding matters:

ffprobe input.3gp

If the audio stream is already AAC, copy it into an ADTS AAC file instead of re-encoding:

ffmpeg -i input.3gp -map 0:a:0 -vn -c:a copy -f adts output.aac

Stream copying preserves the existing AAC data, but works only when the source stream is compatible with the ADTS output. If FFmpeg cannot copy the stream, use the re-encoding command. FFmpeg's standard AAC encoder normally produces AAC-LC, which is accepted by many older players; devices with strict codec requirements should be tested before batch conversion.

How to convert without installing software

You can convert the file for free on 101convert.com: open the 3GP-to-AAC converter, upload the .3gp file, select AAC if an output choice is shown, start the conversion, and download the resulting .aac file. Do not upload recordings containing confidential or sensitive audio.

Quality and compatibility limits

Re-encoding cannot restore detail already lost through AMR compression or an earlier compressed recording. Re-encoding an existing AAC track can reduce quality slightly, so stream copying is preferable when the source and output requirements allow it.

Some applications accept AAC only in ADTS format, while others expect AAC inside M4A or MP4. If a standalone .aac file is rejected, the audio may need to be placed in an M4A container rather than encoded again. Verify the output duration, audio stream, and playback on the target device after conversion.