Talk to a tutor
that never phones home.
Speech recognition, turn detection and text-to-speech all run on your own machine. Ask a question out loud, get an explanation spoken back, and keep going — with the Wi-Fi off and no audio leaving the room.
What makes the conversation work
Four models cooperating on-device: speech recognition, turn detection, the tutor itself, and a voice.
Offline speech recognition
Speech-to-text runs on-device with Parakeet models. Your voice is transcribed on your own machine and no audio is streamed to a server.
Real-time turn detection
A dedicated end-of-utterance model works out when you have finished speaking, so a conversation flows instead of waiting for a fixed pause or a button press.
Voice activity detection
Silero VAD separates speech from room noise, which is what makes hands-free use workable in an actual classroom rather than a quiet studio.
Local text-to-speech
The tutor speaks back using on-device voices. Pick a voice, and it works with the network off like everything else.
Tutors you configure
Build an agent per subject with its own system prompt and model. A physics tutor that works through derivations behaves differently from a language partner.
Explains rather than answers
Agents are set up to work a problem through with you. That is both better pedagogy and the use of AI your school policy almost certainly permits.
Language practice
Speak in a language you are learning and get corrections explained rather than silently applied, with multilingual models handling both sides.
Transcription for lessons
The same speech engine transcribes a recorded lesson or an interview into text you can then summarise or search.
Why voice is the mode that gets used
Typing a question is a small tax, but it is charged every time. It is enough that a student who is stuck on step four of a derivation will usually just stare at it rather than describe the problem in a text box. Speaking removes that tax, and the number of questions asked goes up sharply.
It also changes what kind of question gets asked. Typed questions tend to be well-formed and final. Spoken questions are half-formed, which is exactly the state a student is in when help would be most useful.
Why running it locally matters here more than anywhere else
Text is one thing. A continuous audio stream from a child’s desk is another, and it is the part parents and data-protection officers object to hardest — with reason. A cloud voice assistant means a microphone feed leaving the building.
On-device speech recognition removes the stream. The audio is transcribed on the machine it was captured on and is never transmitted, which turns a difficult conversation into a short one. It also means no per-minute transcription bill, so a student can talk for an hour without anyone watching a meter.
Frequently asked questions
Is there an AI voice tutor that works offline?+
Yes. Grout runs speech-to-text, turn detection and text-to-speech on-device, alongside a local language model, so you can hold a spoken conversation with a subject tutor with the network disconnected. No audio is streamed anywhere.
Does the AI tutor speak out loud?+
Yes. On-device text-to-speech reads the tutor’s replies aloud with a voice you choose. Because the voices are local, this works offline and has no per-minute cost.
Can I use voice input instead of typing?+
Yes, anywhere in the studio. Voice activity detection and end-of-utterance detection mean you can talk naturally rather than holding a button, which matters when your hands are on a worksheet.
Is it safe for a child to talk to an AI tutor?+
The specific risk with voice assistants is that a child’s speech is recorded and sent to a company. On-device processing removes that transfer — the audio is transcribed locally and never uploaded. Beyond that, guardians can see activity and set screen time limits.
Can I make a tutor for a specific subject?+
Yes. Each agent has its own system prompt and model, so you can configure a chemistry tutor that insists on balanced equations and a separate essay coach that never writes prose for you.
Does voice work in languages other than English?+
The studio ships multilingual speech and language models, and the interface itself runs in several languages. Quality varies by language — widely spoken languages are noticeably stronger than rare ones.
Ask out loud
Free download for Windows and macOS. Speech in, speech out, nothing uploaded.
Download Grout free