Convert Audio to Any Format
Convert between MP3, WAV, FLAC, AAC and 24 more audio formats. Pick the quality you want, or keep it lossless.
Drop your audio here
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What You Can Control
Use a quality preset, or set the exact bitrate yourself.
Quality Presets
Low, Medium, High, or Ultra. Each preset sets bitrate, sample rate, and channels together.
Custom Bitrate
Choose Custom in the quality menu to set any bitrate from 64k to 320k.
Lossless Output
Convert to FLAC, WAV, AIFF, or TTA to keep every sample of the original.
Batch Conversion
Drop several files at once and convert them all in a single pass.
Which Audio Format Should You Use?
Every size below is a real encode of the same 3-minute, 44.1 kHz stereo track.
| Format | Type | Bitrate | Size (3 min) | Quality | Best For | Support |
|---|---|---|---|---|---|---|
| MP3 | Lossy | 192 kbps | 4.12 MB | Good | Everyday music and podcasts | Universal |
| AAC | Lossy | 195 kbps | 4.18 MB | Close to source | Apple devices, streaming | Very broad |
| OPUS | Lossy | 145 kbps | 3.11 MB | Best at low bitrates | Voice chat, web audio | Modern browsers |
| OGG | Lossy | 137 kbps | 2.95 MB | Closest to source | Games, open-source apps | Good, not Apple |
| FLAC | Lossless | 468 kbps | 10-15 MB | Identical to source | Archiving, hi-fi listening | Broad, not Apple stock |
| WAV | Uncompressed | 1411 kbps | 30.31 MB | Identical to source | Editing and mastering | Universal |
Measured with FFmpeg 7.1 by encoding one 3-minute 44.1 kHz stereo source to each format. Every lossy format was asked for 192 kbps, but only MP3 delivers that as a constant rate: Vorbis and Opus treat the setting as a target and encode variably, which is why OGG lands at 137 kbps and OPUS at 145 kbps while still measuring closer to the source than MP3. The bitrate column shows what each file actually contains, taken from its size and duration. FLAC varies with the material because it compresses whatever redundancy the recording contains: sparse acoustic tracks land near 10 MB, dense or noisy ones closer to 15 MB.
Which Setting Should You Pick?
Five defensible answers pulled straight out of the numbers above.
1.46 MB, -0.9 dB, 1.17s
The best size-to-fidelity trade in the whole test. It gives up 0.9 of high-frequency detail in 1.46 MB, which is less loss than MP3 manages at 256 kbps in nearly four times the space. Raising Opus to 128 kbps measured the same -0.9 for 0.52 MB more, so there is nothing to gain by going higher.
2.95 MB, -0.0 dB, 1.70s
Measured at -0.0 against the source, the closest result recorded, and it does it in 2.95 MB. AAC needed 320 kbps and 4.84 MB to land slightly behind it.
1.82 MB, -1.4 dB, 1.73s
When the target will not read Opus, this is the next smallest file that stays close to the source: 1.82 MB at -1.4. Dropping to 96 kbps saves only 0.26 MB and nearly triples the loss to 3.8.
4.12 MB, -2.2 dB, 1.11s
MP3 plays on effectively every device ever built, and it encoded faster than every other codec tested, finishing in 1.11s against AAC's 4.14s. At 192 kbps it loses 2.2; going to 320 kbps cuts that to 0.7 but costs 2.75 MB more.
4.82 MB, -0.2 dB, 4.14s
Native across the Apple ecosystem and measured at -0.2. Worth knowing it is the slowest to encode in this test: 4.14s against MP3's 1.11s, and AAC at 320 kbps took 32.73s for no measurable gain.
10.03 MB, zero loss, 0.22s
The only choice when the file is a master you will re-encode from later. FLAC keeps every sample, so it survives repeated conversion where lossy formats compound their losses. It measured 10.03 MB, about 33% of the same audio as WAV, and encoded in 0.22s.
Bitrate, Size, Speed and Quality: Measured
The same 3-minute stereo track encoded 29 ways, with every number measured rather than estimated.
| Format | Target | Real Bitrate | Size | Encode Time | Detail Kept | Quality |
|---|---|---|---|---|---|---|
| MP3 | 96k | 96 kbps | 2.06 MB | 1.01s | -7.6 dB | Audibly dulled |
| AAC | 96k | 99 kbps | 2.12 MB | 2.82s | -6.4 dB | Audibly dulled |
| OPUS | 96k | 68 kbps | 1.46 MB | 1.17s | -0.9 dB | Very close |
| OGG | 96k | 73 kbps | 1.56 MB | 2.10s | -3.8 dB | Audibly dulled |
| MP3 | 128k | 128 kbps | 2.75 MB | 1.03s | -5.2 dB | Audibly dulled |
| AAC | 128k | 131 kbps | 2.81 MB | 3.07s | -4.0 dB | Audibly dulled |
| OPUS | 128k | 92 kbps | 1.98 MB | 1.21s | -0.9 dB | Very close |
| OGG | 128k | 85 kbps | 1.82 MB | 1.73s | -1.4 dB | Noticeable on good gear |
| MP3 | 192k | 192 kbps | 4.12 MB | 1.11s | -2.2 dB | Noticeable on good gear |
| AAC | 192k | 195 kbps | 4.18 MB | 3.42s | -1.4 dB | Noticeable on good gear |
| OPUS | 192k | 145 kbps | 3.11 MB | 1.40s | -0.8 dB | Very close |
| OGG | 192k | 137 kbps | 2.95 MB | 1.70s | -0.0 dB | Nearly identical |
| MP3 | 256k | 256 kbps | 5.50 MB | 1.22s | -1.2 dB | Noticeable on good gear |
| AAC | 256k | 225 kbps | 4.82 MB | 4.14s | -0.2 dB | Nearly identical |
| OPUS | 256k | 207 kbps | 4.43 MB | 1.52s | -0.8 dB | Very close |
| OGG | 256k | 175 kbps | 3.75 MB | 1.79s | -0.2 dB | Nearly identical |
| MP3 | 320k | 320 kbps | 6.87 MB | 1.29s | -0.7 dB | Very close |
| AAC | 320k | 226 kbps | 4.84 MB | 32.73s | -0.2 dB | Nearly identical |
| OPUS | 320k | 268 kbps | 5.75 MB | 1.67s | -0.8 dB | Very close |
| OGG | 320k | 225 kbps | 4.84 MB | 1.84s | -0.2 dB | Nearly identical |
| WMA | 192k | 276 kbps | 5.92 MB | 0.56s | -0.5 dB | Nearly identical |
| AC3 | 192k | 192 kbps | 4.12 MB | 0.39s | -0.7 dB | Very close |
| MP2 | 192k | 192 kbps | 4.12 MB | 0.35s | -12.4 dB | Audibly dulled |
| AMR | 12.2k | 13 kbps | 0.27 MB | 0.69s | -32.7 dB | Speech only |
| ALAC | Lossless | 473 kbps | 10.15 MB | 0.40s | 0.0 dB | Bit-perfect |
| WAV | Lossless | 1412 kbps | 30.29 MB | 0.12s | 0.0 dB | Bit-perfect |
| AIFF | Lossless | 1412 kbps | 30.29 MB | 0.13s | 0.0 dB | Bit-perfect |
| TTA | Lossless | 511 kbps | 10.97 MB | 0.34s | 0.0 dB | Bit-perfect |
| WV | Lossless | 928 kbps | 19.92 MB | 0.37s | 0.0 dB | Bit-perfect |
Opus at 96 kbps stays within 0.9 dB of the source in 1.46 MB. MP3 needs 5.50 MB at 256 kbps to land at 1.2 dB, so Opus is 3.8x smaller and closer to the original at the same time. MP3 is worth keeping when a device or platform will not read anything else, which is still most of them.
Encoded with FFmpeg 7.1 on one 3-minute 44.1 kHz stereo source. Size and encode time are read from the output file; real bitrate is the file size divided by duration, which is why it can sit below or above the target. Quality is the change in energy above 16 kHz against the untouched source: lossy encoders discard the top of the spectrum first, so the drop shows how much detail each setting gave up. Lossless formats measure 0.0 dB by definition, which is what makes them a useful control on the method. AMR is listed at its native 12.2 kbps and 8 kHz because it is a telephony codec, so its figure reflects a different job rather than a worse encoder. The metric tracks retained detail, not listening preference, and it is not a substitute for a blind listening test.
Best Audio Format by Platform
Where the audio is going decides the format. Here is what each platform expects.
Spotify & Streaming
Upload lossless FLAC or WAV. Streaming services re-encode anyway, so give them the best source you have.
Podcast Hosting
Use MP3 at 128k mono or 192k stereo. It is the format every podcast platform and app accepts.
YouTube & Video
Pair video with AAC audio. It is the codec YouTube expects and it survives re-encoding well.
Apple Devices
Use M4A or AAC for compressed, AIFF for uncompressed. All play natively in the Apple ecosystem.
Websites & Web Apps
Use OPUS in an Ogg or WebM container for the smallest files, with an MP3 fallback for older browsers.
Voice & Calls
OPUS for modern voice apps, AMR or GSM for phone-system recordings. All are tuned for speech, not music.
Home Cinema
AC3 (Dolby Digital) or DTS carry 5.1 surround for DVD and Blu-ray playback.
Audio Editing
Work in WAV or AIFF. Uncompressed audio avoids stacking generation loss with every save.
Supported Audio Formats
Convert between 26 different audio formats - from modern streaming formats to legacy professional types
Common Formats
Lossy MPEG audio, the universal standard.
Best for music, podcasts, and sharing.
Plays on virtually every device ever made.
Advanced Audio Coding, the successor to MP3.
Best for Apple devices and streaming.
Better quality than MP3 at the same bitrate.
MPEG-4 audio container, usually AAC inside.
Best for iTunes and Apple libraries.
The default for Apple Music downloads.
Open Ogg container with the Vorbis codec.
Best for games and open-source projects.
Royalty-free with solid compression.
Modern low-latency codec from Xiph.
Best for voice chat and web streaming.
Beats MP3 and AAC at low bitrates.
Lossless
Free Lossless Audio Codec.
Best for archiving and hi-fi listening.
Halves the size with zero quality loss.
Uncompressed PCM audio.
Best for editing and mastering.
Perfect quality, but very large files.
Apple's uncompressed audio format.
Best for Mac editing and production.
The Apple counterpart to WAV.
True Audio lossless codec.
Best for real-time lossless recording.
Fast to encode with modest compression.
WavPack hybrid lossless format.
Best for archiving with a lossy preview.
Stores lossless and lossy in one file.
Surround & Broadcast
DTS surround sound format.
Best for Blu-ray and home cinema.
A higher-bitrate rival to Dolby Digital.
MPEG-1 Audio Layer II.
Best for broadcast and DVD audio.
Still used in digital radio and TV.
Matroska audio container.
Best for multi-track audio and audiobooks.
Holds many tracks and chapters in one file.
Speech & Telephony
Adaptive Multi-Rate speech codec.
Best for voice recordings on phones.
Tuned for speech, poor for music.
GSM 06.10 telephony codec.
Best for phone-quality voice archives.
Very small files at telephone quality.
Speex speech codec in an Ogg container.
Best for archived voice recordings.
Superseded by Opus.
A-law companded PCM.
Best for European telephony systems.
8-bit telephone-standard audio.
Mu-law companded PCM.
Best for North American telephony.
The US and Japan telephone standard.
Raw & Legacy
Raw uncompressed PCM samples.
Best for audio pipelines and DSP work.
No container, just the sample data.
Signed 16-bit little-endian PCM.
Best for CD-quality raw audio.
The most common raw PCM layout.
32-bit float little-endian PCM.
Best for professional audio processing.
Huge dynamic range, very large files.
AAC in an ADTS transport stream.
Best for streaming and broadcast AAC.
AAC frames that can start mid-stream.
Sun Microsystems audio format.
Best for legacy Unix and Java audio.
One of the oldest formats still in use.
NeXT/Sun SND audio.
Best for vintage Unix audio files.
Closely related to the AU format.
RealAudio streaming format.
Best for opening 1990s audio archives.
Pioneered internet audio, now obsolete.
References
- Web audio codec guide - MDN Web Docs, Mozilla
- RFC 6716: Definition of the Opus Audio Codec - IETF
- RFC 7845: Ogg Encapsulation for the Opus Audio Codec - IETF
- Opus Interactive Audio Codec - Xiph.Org
- Vorbis I Specification - Xiph.Org
- FLAC - Free Lossless Audio Codec - Xiph.Org
- ISO/IEC 11172-3: MPEG-1 Audio (MP3) - International Organization for Standardization
- MP3 encoding guide - FFmpeg Wiki
- AAC encoding guide - FFmpeg Wiki
- High quality audio encoding - FFmpeg Wiki
- FFmpeg Filters Documentation (astats, highpass) - FFmpeg
- Recommended upload encoding settings - YouTube Help, Google
- AudioFormatID - Core Audio Types, Apple Developer
- Recommendation ITU-R BS.1387: Perceptual evaluation of audio quality - ITU