Audio Compressor — free online tool
A WAV recording can reach several tens of megabytes per minute. This tool reduces the size of an audio file by re-encoding it as MP3 at a lower bitrate. Handy for sending by email, uploading to a platform with limits or storing more economically.
Drop a MP3, WAV, AAC file here, or click to choose one
تُعالج مؤقتًا ثم تُحذفDrop a MP3, WAV, AAC file here, or click to choose one
MP3, WAV, AAC
كيفية العمل
The principle of audio compression
The sound is re-encoded as MP3, a lossy codec that discards information the ear barely perceives. An uncompressed CD-quality stereo WAV takes up about 10 MB per minute (1,411 kbit/s), whereas an MP3 at 128 kbit/s weighs only about 1 MB. The saving is therefore considerable, especially on raw recordings from a voice recorder or studio software.
Usage
Drop your MP3, WAV or AAC file, start the compression and download the lightened MP3. Compare the size before and after and listen to the result with the same earphones you will normally use. If the quality disappoints you, start again from the original, never from the already compressed file, so as not to accumulate losses.
Which bitrate for which use
For speech (classes, meetings, podcasts), 64 to 96 kbit/s in mono is enough to keep a clear voice. For music, 128 kbit/s is an acceptable minimum and 192 to 256 kbit/s suit attentive listening. MP3 tops out at 320 kbit/s. It is best not to go too low: below 64 kbit/s, voice turns metallic and the highs disappear.
Compressing a WAV, an MP3 or an AAC
Compressing a WAV is where the gain is greatest, because you start from a lossless format. Recompressing an already light MP3 brings little and adds extra quality loss. An AAC is converted to MP3, which does not always make it lighter, since AAC is more efficient at equal bitrate. This conversion is mostly useful if your device requires MP3.
Difference from the other audio tools
This compressor aims to reduce the size of an existing audio file. To extract the sound from a video, use the audio extractor or the video to MP3 conversion. To remove part of the sound without re-encoding it, the audio cutter is preferable. To simply change format without worrying about size, the MP3 to WAV and WAV to MP3 converters are more direct.
Common mistakes
Avoid compressing the same sound several times, because each pass adds audible artifacts, such as a watery sound or muffled highs. Do not count on compression to repair a clipped or noisy recording either. Always keep the uncompressed original if the audio is valuable, for example a music recording, and keep the lightened version only for distribution.
القيود
The output is an MP3: encoding is lossy and irreversible. Recompressing an already light MP3 or AAC brings little gain and degrades quality. Input formats are limited to MP3, WAV and AAC. The tool does not adjust volume or noise.
الأسئلة الشائعة
What file format will I get?
An MP3 file, playable on virtually every device. The accepted inputs are MP3, WAV and AAC.
How much will my WAV be reduced?
A lot: a CD-quality stereo WAV weighs about 10 MB per minute, versus about 1 MB for an MP3 at 128 kbit/s. The ratio depends on the bitrate chosen.
Does compression damage the sound?
Yes, it is lossy compression. It is often inaudible at 192 kbit/s or more on everyday equipment, but becomes noticeable at low bitrates, especially on music.
Should I compress an existing MP3?
Rarely. Re-encoding an MP3 at a lower bitrate saves a bit of size but adds defects. If possible, start again from the uncompressed source file.
What is the difference from the audio cutter?
The compressor changes the bitrate and therefore the quality to reduce size; the cutter removes sections without touching quality. The two can be combined for a shorter and lighter file.
What bitrate for a spoken podcast?
Between 64 and 96 kbit/s in mono, which gives a clear voice and very light files. For a music podcast, aim for 128 kbit/s or more.