# Wake word Canonical page: https://flit.fyi/glossary/wake-word > A wake word is a spoken phrase that turns a listening device on, like "Hey Siri" or "Alexa". A small always-on model listens for that one phrase and ignores everything else until it hears it. [Glossary](https://flit.fyi/glossary) / [Talking to it](https://flit.fyi/glossary#input) Also: hotword Updated October 4, 2026 Definition A wake word is a spoken phrase that turns a listening device on, like "Hey Siri" or "Alexa". A small always-on model listens for that one phrase and ignores everything else until it hears it. Wake words solve the problem of starting a voice interaction when there is no key to press: a speaker on a shelf, a phone in a pocket. The detector is deliberately tiny and deliberately narrow, tuned to one phrase, so it can run constantly at very low power without transcribing the room. For desktop dictation, a wake word is usually the wrong tool. You are sitting at a keyboard, so a key is faster, more precise, and never triggers by accident. Hands-free dictation on a computer is better served by voice activity detection: arm the tool once, and it starts when you speak. ## Wake word versus voice activity detection Both are always-on listeners, and both run small models, but they answer different questions. A wake-word detector asks "was that my phrase?" and treats everything else as silence. A voice activity detector asks "is that speech at all?" and treats every utterance as a potential dictation. The first is for waking a device that is otherwise asleep; the second is for a tool you have already told to listen. ## The privacy question A wake-word detector has to hear everything to catch the phrase, which is why the question with any always-listening product is what happens to the audio it decides was not the phrase. On a well-built device it is discarded on the device within moments. The recurring news stories about smart speakers come from the moment after the wake word, when audio is sent to a server, and from false triggers that send audio nobody meant to send. ## How to set or change the Siri wake word on a Mac The Mac has one wake word feature built in, and it belongs to Siri. Apple notes that "Hey Siri" or "Siri" may not be available for every device, language, or region, so you may not see every option below. 1. Open the System Settings app on your Mac. 2. Click the Siri settings in the sidebar. Depending on your version of macOS the item is named Siri, or Apple Intelligence & Siri. 3. Find the setting for the phrase Siri listens for. 4. Choose the phrase you want to speak to start Siri: "Hey Siri" or "Siri". 5. Decide whether to turn on "Allow Siri when locked". With it on, the phrase also works when the Mac is locked or in sleep. 6. Say the phrase from where you normally sit to confirm that it responds. ## How does a wake word detector work? Apple’s machine learning team has published a description of the "Hey Siri" detector on iPhone, and it is a good picture of the general design. A very small speech recognizer runs all the time and listens for just those two words. It turns the incoming sound into a confidence score that the phrase was spoken. The check happens in two stages. A low-power, always-on processor runs a small model first. When the score passes a threshold, it wakes the main processor, which checks the same sound again with a larger model. The setup also has you say the phrase several times, so the detector can compare later attempts with your voice. ## Why does a wake word trigger by accident, or not at all? Every wake word detector comes down to a threshold on a confidence score. Set it low and the device wakes for phrases that only sound similar. Set it high and it ignores you. Engineers measure the two errors separately: the false-accept rate is the number of false activations per hour, and the false-reject rate is the share of real attempts that fail. Apple describes one way to soften the trade-off. When a score lands just under the threshold, the system becomes more sensitive for a few seconds, so repeating the phrase triggers it without extra effort. That is why saying a wake word a second time so often works. In Flit Flit has an optional wake word. Turn it on, and with voice activation armed a dictation starts only when you begin with "Hey Flit", or a phrase of your own. Apple's on-device recognizer checks for it, so nothing leaves your Mac. Off by default, and it needs macOS 26. [How Flit starts](https://flit.fyi/#start) - [Hold, tap, and hands-free](https://flit.fyi/#start) - [When the microphone is open](https://flit.fyi/privacy) ## Questions people ask. ### Does dictation software need a wake word? On a computer, no. A key you hold or tap is faster and never misfires. Wake words exist for devices without a keyboard. Hands-free dictation at a desk is better done with voice activity detection, which starts on any speech once you have armed it. ### What is the difference between a wake word and a hotkey? A hotkey is a physical key you press to start listening. A wake word is a phrase the device is always listening for. The hotkey is exact and private; the wake word is convenient when your hands are not on a keyboard. ### Can I say just "Siri" instead of "Hey Siri" on a Mac? On supported Macs, languages, and regions, yes. Open System Settings, open the Siri settings, and choose either "Hey Siri" or "Siri" as the phrase it listens for. ### Does "Hey Siri" work when my Mac is locked? Only if you allow it. Apple says that when "Siri" or "Hey Siri" is on and you turn on "Allow Siri when locked", you can use Siri even if the Mac is locked or in sleep. ### What is a false accept in wake word detection? A false accept is the device waking up when nobody said the phrase. It is counted as false activations per hour, and it is balanced against the false-reject rate, which is the share of real attempts that fail. ## Use cases - [Hands-free & RSI](https://flit.fyi/use-cases/accessibility) ## Related terms - [Voice activity detection](https://flit.fyi/glossary/voice-activity-detection) - [Push-to-talk](https://flit.fyi/glossary/push-to-talk) ## Your voice was always faster. 7 days free, then $19 USD once. No account, no subscription, nothing uploaded. [Download for Mac](https://flit.fyi/download) [Buy now · $19 USD](https://flit.fyi/pricing#personal) macOS 14 or later · Apple silicon