Converts Opus files to M4A format — voice-over-IP, real-time communication, and streaming at very low bitrates with excellent quality to Apple ecosystem. All conversion happens locally in your browser with no file size limits.
Runs on FFmpeg
Content reviewed October 2026 · About Toolzum
Convert M4A audio to uncompressed WAV for DAWs and archival — bit-perfect from ALAC sources. Prep Apple recordings for Pro Tools — local FFmpeg work, unlimited saves.
Convert OGG Vorbis to AAC for Apple and streaming compatibility. Move open audio into mainstream players — local FFmpeg work, unlimited saves.
Convert M4A to AIFF for Logic Pro and GarageBand native ingest. Move Apple audio into pro workflows — local FFmpeg work, unlimited saves.
Play any video backwards — video, audio, or both independently. Create rewind effects for social clips — local FFmpeg work, unlimited saves.
Convert WebM videos to Apple-friendly MOV for Final Cut and QuickTime workflows. Bring web clips into Mac editing — local FFmpeg work, unlimited saves.
Opus (Opus Interactive Audio Codec) uses lossy compressed encoding and is best for voice-over-IP, real-time communication, and streaming at very low bitrates with excellent quality. M4A (MPEG-4 Audio) uses lossy or lossless (AAC/ALAC) encoding and excels at Apple ecosystem — iTunes, iPhones, iPads, and macOS music libraries. Converting between them lets you take advantage of each format's strengths — for example, using a compressed format for sharing and a lossless format for editing. All conversion happens locally in your browser with no file size limits.
Apple Podcasts, iTunes, and iOS players skip Opus — M4A (AAC) plays universally there. Voice shows convert cleanly upward in compatibility.
128 kbps AAC preserves voice fully from 32k Opus sources; music-origin Opus deserves 192k. Match content, not habit.
Yes — M4A with proper tags feeds Apple Podcasts directly. Add chapter marks and artwork before submitting the feed.
No — conversion runs locally in your browser with FFmpeg. Saves never touch a meter — downloads on local tools are unlimited.
Text to Speech (TTS)
Generate natural-sounding speech from text using your browser's built-in voices. Adjust speed and pitch — download your text as .txt.
Audio Cutter
Trim and cut audio files online — MP3, WAV, M4A, FLAC, and OGG. Set start and end times with sliders, then download the trimmed MP3 clip.
MP3 to WAV
Converts MP3 files to WAV format — universal music playback and sharing across all devices and platforms to professional audio editing, mastering, and archival in DAWs and production software. All conversion happens locally in your browser; files up to 100 MB each.
Speech to Text
Dictate live microphone speech to text in multiple languages through your browser's speech service. Live captions for meetings and notes — free to start, no Toolzum account needed.
MP3 Compressor
Shrink MP3 files by lowering bitrate with quality presets — fit podcasts into feed limits. Cut a 50 MB episode to 15 MB cleanly — local FFmpeg work, unlimited saves.
Apple Music Preview Extractor
Extracts publicly available 30-second audio preview clips from Apple Music by resolving the store URL. Free to start with no signup.