Block's Dessa Voice AI Runs Locally on a MacBook

Block, the company behind Square and Cash App, has shown off a voice AI called Dessa that talks with you in real time and, according to Block, runs on a single high-end MacBook. The catch: you can't try it yet. TechCrunch flagged the local-running detail on X, and Block's own Dessa page has the details.

What happened

Dessa comes from a small research lab inside Block that reports directly to Jack Dorsey. The team says it trained the model from scratch on recordings of human conversation only. No text and no pretrained language model. Audio goes in and audio comes out.

It's what's called full-duplex, so it can listen and speak at the same moment instead of waiting for you to finish. In the demo clips on Block's page it laughs mid-sentence, says "yeah" while you talk, and finishes a movie title the speaker forgets. Block says it runs faster than real time on a MacBook Pro with an M4 Max chip or better, and that the whole model was trained on one NVIDIA GB200 NVL72 rack.

Dorsey summed it up on X as "speech to speech. no llm," India Today reports. TechCrunch notes there's no public access for now. Block is only letting a small group of AI safety researchers in early to look for risks.

Why it matters

Most voice assistants still turn your speech into text, think about the text, then read an answer back. That's why they feel slow, and why they miss things like tone and sarcasm. A model that works on sound directly could feel a lot more natural. Running on a laptop also means no audio has to leave your machine, which is a big deal for privacy.

I'd keep expectations in check, though. Block hasn't shared a parameter count, a price or any published evaluation, and the clips are hand-picked demos. A voice this lifelike also makes phone scams easier, which is likely why safety testers get it first.

What to do

• Listen to the samples on Block's page if you're curious. That's the only way to hear it right now.
• Be wary of anything selling "Dessa downloads". Block hasn't released weights, an app or an API, so a download link today is fake.
• Want local AI now? Text models already run offline. My guide on running DeepSeek or Llama locally with LM Studio shows how on a normal PC.