Convert MP4 to WAV Online
Convert MP4 video to uncompressed WAV audio. Free, in your browser, no file uploads.
.mp4 · up to 100 MB
What you can do
The fastest MP4 to WAV converter in the browser
Podcast production
Extract WAV audio from video recordings of interviews, webinars, and events to edit them as podcast episodes.
100% private
Your MP4 video never leaves your device. FFmpeg.wasm runs in WebAssembly, no server, no cloud.
Music sampling
Extract audio from any MP4 — YouTube, Instagram, film scoring — to WAV for sampling in your DAW.
AI transcription
Uncompressed WAV for Whisper, AssemblyAI, Google Speech-to-Text, and any automatic transcription pipeline.
How it works
Three steps, no hassle
Upload your MP4 file
Drag or select your .mp4 video — downloaded YouTube video, screen recording, Instagram video, or podcast clip. Up to 500 MB, no signup.
Decoding to WAV
FFmpeg.wasm extracts the AAC audio from the MP4 and decodes it to uncompressed PCM WAV directly in your browser. No servers, no privacy compromise.
Download your WAV
Get the WAV ready for Audacity, Pro Tools, Whisper, GarageBand, or any production or transcription software.
FAQ
Got questions?
Most professional audio editing software — Pro Tools, Nuendo, Reaper, Adobe Audition — accepts WAV as the native working format but can have issues with AAC audio inside an MP4 container, especially in older versions or strict codec configurations. Speech recognition and transcription systems (OpenAI Whisper, Google Speech-to-Text, AWS Transcribe, AssemblyAI) have optimal performance with uncompressed PCM WAV, which eliminates AAC decoding overhead and ensures no codec artifacts in the analyzed audio. For sampling in music production, WAV is the standard working format in DAWs: it allows sample-accurate editing, glitch-free looping, and plugin processing without intermediate re-encoding.
Yes, with the technical consideration that audio in MP4 is typically encoded in AAC, which is a lossy codec. Converting AAC to PCM WAV is a lossless decoding: the WAV contains exactly the same audio as the decoded AAC, with no additional degradation. What AAC discarded in the original encoding is not recovered, but nothing additional is lost in the conversion. For audio recorded directly on recent devices (iPhone, GoPro, DSLR camera), AAC is typically high quality (256 kbps or more) and the resulting WAV is perfectly adequate for professional use.
Yes. YouTube videos downloaded in MP4 format (using youtube-dl, yt-dlp, or browser extensions) contain AAC-LC or Opus audio at 128-256 kbps. Convertir.ai extracts and decodes that audio to uncompressed PCM WAV. It is one of the fastest ways to obtain YouTube video audio in WAV format for editing, sampling, or transcription, without needing additional tools.
Uncompressed PCM WAV is significantly larger than the original MP4 because it applies no compression. A 100 MB MP4 with 128 kbps AAC audio can produce a WAV of 200-500 MB depending on duration (WAV at 44.1 kHz, 16-bit, stereo takes approximately 10 MB per minute). For long 30-60 minute videos, the WAV can be 300-600 MB. If size is a concern, consider converting to FLAC (lossless compression) as an archival alternative, or to high-quality MP3/AAC for distribution.
The current version processes one file at a time. For batch conversion of multiple MP4 to WAV, the most efficient alternative is using FFmpeg from the command line: for f in *.mp4; do ffmpeg -i "$f" -vn -acodec pcm_s16le "${f%.mp4}.wav"; done in bash, or the PowerShell equivalent for Windows. This command processes all MP4s in the current directory and generates one WAV per file.
Yes. MP4 is the universal recording standard for most current cameras and recording devices: GoPro (H.264 or H.265, AAC or PCM audio), DJI (H.264 or H.265, AAC audio), Canon DSLR and mirrorless (H.264 or Cinema RAW Light, PCM audio), Sony Alpha (H.264 or XAVC, PCM or LPCM audio), Fujifilm (H.265, PCM audio). FFmpeg correctly decodes audio from all these devices, including MP4 variants with manufacturer-specific extensions.
Convert MP4 to WAV: the complete guide to getting uncompressed audio from any MP4 video
Converting MP4 to WAV is one of the most searched audio-video processing operations in 2025. The MP4 format (MPEG-4 Part 14, specified in ISO/IEC 14496-14 as a profile of the ISO Base Media File Format) is the universal standard for internet video: YouTube, Instagram, TikTok, Netflix, Zoom and Microsoft Teams streaming, iPhone and Android recordings, GoPro and DJI videos, and exports from Premiere Pro, Final Cut Pro, and DaVinci Resolve all use MP4 as the distribution format. Audio inside an MP4 is typically encoded in AAC-LC (Advanced Audio Coding Low Complexity), the audio codec developed by Fraunhofer, Dolby, Sony, and AT&T as the successor to MP3, standardized in ISO/IEC 13818-7 in 1997 and adopted as the standard MPEG-4 audio codec in 1999. Converting that AAC audio to uncompressed PCM WAV allows working with it in any professional tool without codec restrictions.
High-frequency use cases for MP4 to WAV conversion cover a broad spectrum of professional and creative needs. In podcast production: creators who record video interviews (Zoom, Google Meet, direct iPhone recording) need to extract the audio to WAV to edit it in Audacity, Adobe Audition, or Descript, apply noise reduction, level volumes with normalization, add intro music, and export to the final episode's MP3 format. In music production and sampling: hip-hop, trap, lo-fi, and electronic music producers extract dialogue fragments, sound effects, rhythmic foundations, and sound textures from films, documentaries, and YouTube content downloaded in MP4, converting them to WAV to chop, pitch, and process with effects in FL Studio, Ableton Live, Logic Pro, or MPC software. In automated transcription: speech recognition systems based on Transformer models like OpenAI's Whisper (released in September 2022, with large-v3 and turbo versions available in 2024) have optimal performance with 16 kHz mono or 16/44.1 kHz stereo PCM WAV audio, significantly better than compressed MP4 in many pipeline implementations.
Convertir.ai runs the MP4 to WAV conversion entirely in the user's browser via FFmpeg.wasm, the compilation of FFmpeg (version 6.x, compiled with Emscripten to WebAssembly) that allows running the complete conversion engine in a WebAssembly worker without external servers. The technical process involves: parsing the ISOBMFF/MP4 container using libavformat to identify and separate media tracks (h264/hevc video, aac/mp3/opus audio, subtitles); extracting audio samples from ISOBMFF boxes (moof/mdat for fragmented streaming, or moov/mdat for non-fragmented MP4); decoding the AAC-LC stream using FFmpeg's native implementation (or libfdk-aac if available in the build), which produces PCM samples in 32-bit floating point format internally; converting to 16-bit integer PCM (pcm_s16le) or 24-bit (pcm_s24le) depending on the original audio bit depth; and writing the PCM data to a RIFF/WAV container with the fmt chunk specifying the sample rate (48 kHz for standard camera video, 44.1 kHz for audio-derived content, or the file's native rate), bit depth, and channel count. The entire process, including FFmpeg.wasm decoding, runs in an independent Web Worker to avoid blocking the browser interface, with progress reported in real time.