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Convert Any Audio File Instantly, in Your Browser
A free online audio converter for MP3, WAV, FLAC, OGG, AAC, M4A, OPUS and WMA. Upload one file or a whole batch, pick a format, download the results, the conversion runs entirely on your device, so your audio is never sent anywhere.
Supported formats
Convert between every common audio format
Bring in almost any audio file, the converter reads dozens of source formats, and export to the format you actually need.
Also read as source input: AMR, AC3 and other common formats.
How it works
Three steps, zero uploads
Choose your files
Drag in one or more audio files, or click to browse. Everything loads straight into your browser's memory, nothing leaves your device yet.
Pick a format
Select the output format you need. A local, WebAssembly build of FFmpeg does the actual encoding on your device.
Download the result
Once conversion finishes, download the new file directly. Close the tab and there's no trace left behind.
Why it's private
No server ever sees your audio
Most "free" online converters work by uploading your file to a server, converting it there, and sending it back, which means a copy of your audio passes through someone else's infrastructure, even if briefly.
This tool works differently. It loads a WebAssembly build of the open-source FFmpeg engine into your browser tab and runs the entire conversion on your own device's CPU. Your file is read into local memory, converted, and offered back to you as a download, it never crosses the network.
That also means it keeps working even offline once the page and engine have loaded, and there's no queue, no watermark, and no account required.
FAQ
Common questions
How do I convert an audio file to MP3 for free?
Upload your file into the converter above, choose MP3 as the output format, and select Convert. Processing happens in your browser, and a download link appears when it's ready, no account or payment required.
Is it safe to convert audio files online with this tool?
Yes. The conversion engine runs locally in your browser using WebAssembly, so your audio file is never uploaded to a server, nothing leaves your device at any point.
Do you store or keep a copy of my audio files?
No. Files exist only in your browser's memory during conversion and are discarded when you close or refresh the page. Nothing is written to any server or database.
What audio formats can I convert between?
You can bring in most common formats as a source, including MP3, WAV, FLAC, OGG, AAC, M4A, OPUS, WMA and AIFF, and export to MP3, WAV, OGG, FLAC, M4A, OPUS or WMA.
Why does conversion happen in my browser instead of a server?
It keeps your files private, removes upload wait time, and means the tool works without anyone else seeing your data. It's powered by a WebAssembly build of FFmpeg running entirely on your device.
Is there a file size limit?
There's no artificial limit, but very large files depend on your device's available memory and processing power. Most music-length files convert in seconds to a couple of minutes.
Can I convert multiple audio files at once?
Yes. Select or drag in several files at once, choose one output format and set of options, and select Convert to batch process all of them. Each file shows its own progress, and once finished you can download files individually or grab everything together as a single zip.
Format reference
Every file type, encoding, bit depth and sample rate you can convert
Full detail on the exact codecs, bitrates and rates behind each output format, for anyone converting audio for a specific technical spec.
Which audio file types can this converter read as a source?
The converter can read most common audio containers and codecs as input, including MP3, WAV, FLAC, OGG (Vorbis), AAC, M4A, OPUS, WMA, AIFF, AMR and AC3. If your file plays in a standard media player, it will almost always load here without issue.
Which audio file types can I convert to?
You can export to MP3, WAV, AIFF, OGG, FLAC, M4A (AAC or ALAC), AAC, OPUS or WMA. Each output format has its own set of quality, bit depth or encoding options once selected.
What MP3 bitrates are supported?
MP3 output can be encoded at 96 kbps, 128 kbps, 192 kbps, 256 kbps or 320 kbps using the LAME encoder. 128 kbps is a common baseline for speech and casual listening, 192 to 256 kbps suits most music, and 320 kbps is the highest quality MP3 allows.
What bit depths and encodings does WAV support?
WAV output can be encoded as 8-bit, 16-bit, 24-bit or 32-bit linear PCM, as well as 8-bit u-law and 8-bit A-law companded encoding for telephony use. 16-bit PCM at 44,100 Hz is the CD-quality standard; higher bit depths suit studio and archival work.
What's the difference between WAV and AIFF output?
Both are uncompressed PCM audio with essentially identical quality; the difference is container format and platform convention. WAV is more common on Windows and in general use, while AIFF is the standard uncompressed format on Mac and in professional audio tools like Logic Pro and Pro Tools. AIFF output supports the same 8-bit, 16-bit, 24-bit and 32-bit PCM options as WAV.
What's the difference between AAC, M4A and ALAC?
AAC is a lossy compressed audio codec, commonly used at 96 to 320 kbps. M4A is a container format that most often holds AAC audio, which is why "M4A" and "AAC" are frequently used interchangeably. ALAC (Apple Lossless) is a different, lossless codec that's also packaged in an M4A file, offering CD-quality audio at a larger file size than AAC. This converter offers a plain AAC output for a bare .aac file, and an M4A output where you can choose AAC at various bitrates or lossless ALAC.
What sample rates can I convert audio to?
You can set the output sample rate to 8,000 Hz, 16,000 Hz, 22,050 Hz, 32,000 Hz, 44,100 Hz or 48,000 Hz, or leave it unchanged from the source file. 8,000 Hz and 16,000 Hz are typical for phone and voice recordings, 44,100 Hz is CD quality, and 48,000 Hz is standard for video and studio production.
What quality settings are available for FLAC, OGG and OPUS?
FLAC lets you choose a compression level from 0 (fastest, larger file) to 8 (smallest, slowest), with no loss of audio quality either way since FLAC is lossless. OGG Vorbis uses a quality scale from Q2 (about 96 kbps) up to Q10 (maximum). OPUS uses bitrate settings from 32 kbps, suited to voice, up to 192 kbps for high-quality audio.
Can I convert stereo audio to mono, or mono to stereo?
Yes. A channel option lets you set the output to mono or stereo regardless of the source file's original channel layout, alongside the bitrate, encoding and sample rate options for each format.
Telephony formats
Convert audio for phone systems, IVR and VoIP
Support for the specific WAV encodings used by PBX, call recording, IVR and VoIP platforms, for anyone converting audio into a telephony-ready format.
How do I convert audio to 8kHz mono WAV for telephony?
Upload your file, choose WAV as the output format, set the encoding to 16-bit PCM (or u-law / A-law, depending on your system), set the sample rate to 8,000 Hz, and set channels to Mono. This produces the classic narrowband WAV format expected by most phone systems.
What is u-law (μ-law) audio encoding?
u-law, also written mu-law or μ-law, is an 8-bit companded audio encoding used in North American and Japanese digital telephony. It's part of the G.711 standard and is a common requirement for call recordings, IVR prompts and VoIP systems in those regions.
What is A-law audio encoding?
A-law is an 8-bit companded audio encoding used in telephony systems across Europe and most of the rest of the world. Like u-law, it's defined by the G.711 standard, and it's a frequent requirement for PBX prompts and call recordings outside North America and Japan.
What's the difference between u-law and A-law?
Both are 8-bit companded encodings defined by the G.711 standard and serve the same purpose, compressing 16-bit audio down to 8 bits for narrowband telephony. The difference is the companding curve each uses and which region's phone networks adopted it: u-law in North America and Japan, A-law almost everywhere else. Using the wrong one for your system can produce distorted or noisy audio.
What audio format do IVR, PBX and VoIP systems need?
Most IVR, PBX and VoIP platforms, including systems built on Asterisk or FreePBX, expect 8,000 Hz mono WAV files encoded in either u-law or A-law PCM, sometimes alongside plain 16-bit linear PCM at the same rate. Check your specific platform's documentation for which one it expects.
How do I create a G.711 WAV file for Asterisk, FreePBX or Twilio?
Select WAV as the output format, choose u-law or A-law as the encoding, set the sample rate to 8,000 Hz and channels to Mono, then convert. The resulting file matches the G.711 format these platforms use for call prompts, voicemail greetings and recordings.
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