How Murmur Works
From audio file to finished transcript — in five steps, entirely on your Mac.
Five steps, no servers
Drop a file or start recording
Drag an audio or video file into the Murmur window. Or start a recording directly from the menu bar — system audio, microphone, or both at once. Supported formats: MP3, M4A, WAV, MP4, MOV.
Extract audio
For video files, Murmur automatically extracts the audio track. The original file is not modified. For audio files, this step is skipped.
Speech recognition
The Parakeet ASR model (based on NVIDIA NeMo) runs on your Apple Silicon chip's Neural Engine and GPU. It automatically detects the language (25+ supported), transcribes the audio, and assigns statements to different speakers. No internet connection needed.
AI summarization
Qwen 3.5 — a language model with 9 billion parameters — generates a summary directly on your Mac. The summary adapts to the content type: meeting minutes with action items, lecture notes with key concepts, interview highlights, or podcast overview. Each point includes a clickable timestamp.
Encrypted storage
Transcript, summary, and recording are encrypted with AES-GCM before they're written to disk. Everything is searchable in your personal library — with full-text search across all transcripts.
The technology behind it
Parakeet ASR
NVIDIA NeMo-based. Runs via the FluidAudio framework on Apple Silicon. Hardware-accelerated on Neural Engine and GPU.
Qwen 3.5 (9B, 4-bit)
9 billion parameters, 4-bit quantized. Runs via MLXLLM on Apple Silicon. Model size approximately 4 GB.
AES-GCM
Authenticated encryption via Apple CryptoKit. All stored data is encrypted before being written to disk.
Swift + SwiftUI
Native macOS app. Requires Apple Silicon (M1+) and macOS 14 or later. 8 GB RAM minimum, 16 GB recommended.
What never leaves your device
Your audio and video files. Your transcripts. Your summaries. Your recordings. None of it is ever sent to any server.
The only network requests Murmur makes: license verification via Lemon Squeezy (transmits only the license key, no content), software update checks, and the one-time AI model download on first launch.
No user account. No telemetry. No cookies. No analytics in the app. What happens on your Mac stays on your Mac.
Try it
7 days free. Full functionality. No credit card required.
Download Free Trial