Time to First Audio (TTFA) Hardware stream trigger latency |
0.47 ms (Warm standby stream) |
300 – 800 ms (Cloud session spin-up) |
60 – 120 ms (Local device open) |
100 – 250 ms (CoreAudio cold start) |
150 – 350 ms (Siri daemon hook) |
First-Word Preservation Pre-roll circular buffering |
✅ 300 ms rolling ring buffer (0% clipping) |
❌ No pre-roll (clips quick initial words) |
⚠️ Partial debounce buffer |
❌ Cold trigger |
⚠️ OS buffer (variable) |
Real-Time Factor (RTF) Lower is faster (processing time / audio duration) |
0.045x (whisper.cpp Base) 0.190x (Parakeet v3) |
0.150 – 0.350x (Cloud API roundtrip + queue) |
0.080 – 0.150x (Local Whisper base/small) |
0.060 – 0.120x (whisper.cpp engine) |
0.100 – 0.200x (SpeechKit framework) |
Cursor Injection Latency Release trigger to text typed in field |
< 5 ms (Direct native Enigo paste) |
180 – 450 ms (Network payload delivery) |
10 – 30 ms (Synthetic accessibility paste) |
N/A (Primarily file/window export) |
15 – 50 ms (Accessibility API) |
Network Dependency & Jitter Impact of offline or high ping |
✅ 0 ms (Zero egress, works in airplane mode) |
❌ Complete outage if offline or spotty Wi-Fi |
⚠️ Local models work offline |
✅ Fully offline |
⚠️ Offline requires manual offline pack |
Memory Footprint (RAM) Idle / Active transcription state |
~85 MB idle / ~290 MB active |
~320 MB (Electron / Chromium shell) |
~220 MB idle / ~650 MB active |
~380 MB idle / ~800 MB active |
Built into macOS com.apple.speech system |
Annual Cost Subscription or license fee |
$0 / Free forever |
$120 – $180 / year |
$30/yr or $149+ Lifetime |
€39 (~$43) One-time |
Included with macOS |