Audio Converter

Audio conversion explained: formats, quality and real-world use

An audio converter changes how a recording is encoded so that it plays on the device, app or website you need, or so that it takes up less room. This page explains which format fits which job, what happens to quality when you convert, and how to get a clean result in a few clicks.

Common uses

Lossy versus lossless

Lossless formats (WAV, FLAC, ALAC, AIFF) keep every detail of the original; lossy formats (MP3, AAC, OGG, Opus, WMA) throw away sounds that are hard to hear to save space. Converting from lossy to lossless makes the file bigger but cannot restore what was removed, so always start from the best original you have and convert once.

Choosing a bitrate

Bitrate is the amount of data per second. For speech 48 to 64 kbps mono is plenty. For everyday music 128 to 192 kbps (MP3) or 96 to 160 kbps (AAC, Opus) is hard to tell from the original on normal speakers and headphones. 256 to 320 kbps suits critical listening. The live size estimate shows what your choice means before you convert.

Sample rate, channels and bit depth

44.1 kHz is CD quality and 48 kHz is the standard for video. Mono halves the size of a stereo file and is ideal for single-voice recordings. Bit depth only applies to uncompressed and lossless formats such as WAV, AIFF and FLAC - the full list is in the guide to the Advanced settings below.

Advanced settings guide: presets

Open 'Advanced audio settings' and start with a preset - it fills every box for a typical job and you can still change any of them. Voice note (mono, 32 kbps, 16 kHz) is for WhatsApp-style messages. Podcast and Audiobook (mono, 64 kbps) keep speech clear and small. Music (192 kbps) and Streaming (256 kbps) match what music services use. High quality (320 kbps) is the maximum for MP3. CD quality (16-bit, 44.1 kHz), Studio (24-bit, 48 kHz) and Mastering (24-bit, 96 kHz) are for lossless formats. Video / DVD uses 48 kHz, the standard for film and TV.

Advanced settings guide: bitrate

Bitrate is measured in kilobits per second (kbps) and decides how much data every second of sound gets. The list shows the standard steps of the format you picked: MP3 from 8 to 320 kbps, AAC from 16 to 320, Opus from 8 to 510, MP2 from 32 to 384, WMA from 32 to 160 and Vorbis from about 45 to 500 (Vorbis is quality-based, so your choice is matched to the nearest quality level). As a rule of thumb: 16 to 32 kbps is tiny voice, 64 kbps is clear speech, 128 kbps is standard music, 192 kbps is good music, 256 to 320 kbps is best lossy quality. MP3 below 32 kbps is only defined for lower sample rates, so the tool automatically switches to 22.05 or 16 kHz for you; Opus allows up to 256 kbps per channel, so for a mono source a higher choice is lowered to 256 kbps. Lossless formats (WAV, FLAC, ALAC, AIFF, WavPack) have no bitrate - their size depends on sample rate, bit depth and channels.

Advanced settings guide: CBR and VBR

Constant bitrate (CBR) spends the same amount of data every second: the file size is easy to predict and every player and streaming system accepts it. Variable bitrate (VBR) gives complex passages more data and silence less, which usually sounds better at the same average size. VBR is offered for MP3 and Opus; with Opus, choosing CBR turns variable bitrate off.

Advanced settings guide: sample rate

The sample rate is how many times per second the sound is measured. The standard values are 8 kHz (telephone), 11.025 / 12 / 16 kHz (low-quality or wideband speech), 22.05 / 24 kHz (speech and small files), 32 kHz (broadcast and some video), 44.1 kHz (CD and music), 48 kHz (video, film, broadcast), 64 / 88.2 / 96 kHz (high resolution) and 176.4 / 192 kHz (mastering, lossless and WAV-type formats only). Only the rates a format really supports are listed: MP3 goes up to 48 kHz, and Opus always uses 8, 12, 16, 24 or 48 kHz. Raising the rate above your original never adds detail, it only makes the file bigger.

Advanced settings guide: channels

Mono (one channel) halves the size and is perfect for speech, lectures and phone recordings. Stereo (two channels) keeps left and right for music. If you pick stereo for a mono recording, the same sound is simply played on both sides. Formats such as AMR and Speex are always mono and fixed by their standards, so those boxes are hidden.

Advanced settings guide: bit depth

Bit depth is the precision of each sample. 8-bit is very small and noisy (old games, telephony). 16-bit is CD quality and the safe choice for sharing. 24-bit is the studio standard and gives more room for editing. 32-bit integer and 32-bit floating point are used by editors and DAWs so that loud and quiet parts are never clipped while you work. WAV offers 8, 16, 24, 32 and 32-bit float; AIFF and AU offer 8, 16, 24 and 32; CAF and Wave64 offer 16, 24, 32 and 32-bit float; FLAC and ALAC offer 16 and 24. Lossy formats do not have a bit depth.

Advanced settings guide: FLAC compression level

FLAC is lossless: the sound is bit-for-bit identical at every level. The level (0 to 8) only decides how hard the encoder works. 0 is the fastest and the largest file, 5 is the standard default, 8 is the slowest and the smallest file. The difference between level 5 and 8 is usually only 1 to 2 percent of the size.

Advanced settings guide: loudness and metadata

Normalize loudness applies the EBU R128 broadcast standard at -16 LUFS with a -1.5 dB true-peak ceiling, which is what podcast platforms and many streaming services expect. Quiet recordings become louder and very loud ones softer. Remove tags and metadata deletes title, artist, album art, comments, encoder name and location data - useful for privacy and it makes the file slightly smaller.

Advanced settings guide: size estimate

Under the settings a live estimate shows the approximate size of the result. It uses the real duration of your files (read in your browser, nothing is uploaded) and your chosen bitrate or sample rate, bit depth and channels. Lossless sizes are an average - the real size depends on the material.

Normalisation and metadata

Loudness normalisation (EBU R128) brings quiet and loud recordings to a similar volume so you do not keep reaching for the volume knob. You can also strip tags such as title, artist, location and device information before sharing a file publicly.

Special and professional formats

Besides the everyday formats, the converter writes TTA (lossless), IMA ADPCM, A-law and mu-law WAV (telephony and small files), GSM and AMR-WB (voice), Creative VOC, headerless RAW PCM and AAC inside an MP4 file. Multi-channel recordings such as 5.1 are kept in formats that support them and mixed down to stereo for formats that do not (MP3, WMA, MP2, VOC).

Big files and batches

You can add dozens of files at once and each is converted independently, so one broken file never stops the others. Recordings up to 200 MB in total are uploaded in safe pieces with automatic retry, so a short network drop does not restart everything.

Privacy

No account is needed. Files are processed on the server only for the conversion, are never opened by a person or shared, and are deleted two minutes after your download has finished (a result nobody downloads is removed after 30 minutes).

Troubleshooting

Available in 55 languages

The whole site - menus, buttons, guides and messages - can be switched to 55 languages, including English, Hindi, Bengali, Tamil, Telugu, Marathi, Gujarati, Kannada, Malayalam, Punjabi, Odia, Assamese, Nepali, Urdu, Arabic, Spanish, French, German, Portuguese, Italian, Russian, Turkish, Japanese, Korean and Chinese. Use the language menu in the top bar; your choice is remembered, and the file formats and tools work exactly the same in every language.