Audio Formats for Film Makers

Professional film production uses 48 kHz sample rate for all audio — not 44.1 kHz (the CD standard). This was established as the broadcast and film video standard and is required for sync with video at 24, 25, or 29.97 frames per second. Bit depth for production recording: 24-bit is standard. Field recorders (like Zoom, Sound Devices, Lectrosonics) default to 24-bit 48 kHz WAV. This gives sufficient headroom and dynamic range for the exposure variation common in location recording. Format: WAV (Broadcast WAV, or BWF) is the production standard. BWF is a WAV file with additional metadata including timecode, date, scene/take information, and a unique ID. Professional field recorders write BWF files natively. Edit systems like Avid, Premiere, and DaVinci Resolve read BWF timecode for automatic sync.

Film makers frequently need to extract audio from video files — pulling the audio from a MOV or MP4 to edit separately, or extracting a reference track for comparison. The correct output format for extracted video audio depends on the next step: For editing in a DAW: extract as WAV. Uncompressed, 48 kHz, 24-bit if the source video had 24-bit audio. This feeds cleanly into Pro Tools, Reaper, Logic Pro, or any other DAW. For a quick reference listen: WAV or even MP3 is fine. For sending to a colorist or sound designer: WAV is the safe interchange format. Avoid sending compressed audio (AAC, MP3) in professional handoffs. AudioUtils can extract WAV or MP3 from MOV and MP4 files directly in the browser, which is useful for quick extractions without launching a full NLE session.

In post-production, audio passes through several stages: editing (assembling dialogue, SFX, music), mixing (balancing levels, spatial placement, EQ), and mastering (final level adjustments, format preparation for delivery). All editing and mixing should happen at full quality — 24-bit 48 kHz WAV or AIFF. No lossy formats during post. The final mix is exported as WAV stems or a stereo mix before the mastering stage. Mixers deliver to streaming platforms as: Stereo WAV at 48 kHz 24-bit (most platforms accept or require this). Dolby Atmos or 5.1 surround for premium streaming tiers. Netflix, Disney+, and Amazon Prime have specific audio delivery specifications — typically -27 LUFS loudness for dialog and defined peak limits. Missing these specs causes automatic rejection at delivery.

MOV and MP4 are the dominant video containers for film workflows. For audio purposes: MOV (QuickTime): Apple's native container. Used by Final Cut Pro, iPhones, and many cameras. Supports multichannel audio, timecode, and ProRes codecs. Audio is typically AAC or PCM. MP4 (MPEG-4): universally compatible container. Used by most cameras, Android devices, and web platforms. Also supports multichannel audio. Audio is typically AAC, AC-3, or MP3. For post-production handoffs between Apple and Windows systems, MP4 is safer — MOV requires QuickTime on Windows (not always present). H.264 or H.265 MP4 with AAC audio plays everywhere without codec installations. When extracting audio from either container for editing, always output WAV — not the AAC or MP3 that was in the container.

Delivery requirements vary by platform and distributor. General checklist: Dialogue clarity: -27 LUFS integrated (Netflix standard), -23 LUFS for broadcast (EBU R128). Peak limit: -2 dBTP true peak for broadcast; -1 dBTP for Netflix and most streaming. Format: WAV 24-bit 48 kHz for stereo mixes. Some platforms also want a FLAC or high-quality AAC in parallel. Surround: 5.1 and Dolby Atmos deliverables are required by major platforms for premium releases. For film festival submissions: check each festival's requirements individually — many still ask for WAV files on a USB drive. For internal archival: keep all audio stems as 24-bit 48 kHz WAV or FLAC. Compress to AAC only for reference or streaming copies — never discard the lossless masters.

Common quick conversions film makers need: MOV to WAV: extract the audio track from a camera clip for DAW editing. AudioUtils handles this in the browser — useful during pre-production when a full session is not set up. MP4 to WAV: same purpose, different container. WAV to MP3: create a compressed reference copy to send for approval review. Reviewers do not need full-quality WAV — an MP3 at 192 kbps is fine for listening notes. FLAC to WAV: some older edit systems do not support FLAC input. Convert archived audio to WAV before importing. AudioUtils performs all of these conversions directly in the browser. Files never leave your machine — useful on productions with data security requirements.