What is on-device AI?

How it works

An AI model is a file of learned weights plus code that runs it. On-device AI downloads that file to your machine once, then runs it using your CPU, GPU or a dedicated neural processor. Apple Silicon Macs, recent PCs and phones all have hardware that speeds this up.

To fit on consumer hardware, on-device models are usually smaller than the largest cloud models, or are quantized: their numbers are stored with less precision, which cuts memory use substantially with a modest loss in quality.

The trade-offs

On-device and cloud AI each have real advantages:

• Privacy: on-device keeps files, transcripts and prompts on your machine. Cloud AI requires trusting the provider with them.
• Offline use: on-device works on a plane or in a secure room. Cloud AI needs a connection.
• Cost: on-device has no per-minute or per-token fees after the one-time download. Cloud AI is usually metered.
• Capability: the largest cloud models are more capable at open-ended reasoning than anything that fits on a laptop.
• Speed and battery: on-device depends on your hardware. A long transcription can keep the fans busy; the cloud offloads that work.
• Storage: models take disk space, from a few hundred megabytes to several gigabytes.

What it's good at

Tasks that are well-defined and repeated over lots of data suit on-device AI well: transcription, embeddings for search, OCR, face and voice matching, and summarizing or answering questions over your own documents. These don't need the biggest possible model, and they involve exactly the kind of material, like recordings of meetings or family videos, that people are reluctant to upload.

Privacy is also about more than secrecy. Some recordings, like client calls, depositions or medical conversations, may be covered by contracts or rules about where they can be stored and processed. Keeping the processing on a machine you control makes those questions much simpler to answer than working through a third party's data handling terms.

How to check a claim

“Local” is sometimes used loosely. A useful test: disconnect from the internet after the models have downloaded and see whether the feature still works. You can also watch network activity with a firewall or monitoring tool while the app processes a file.

In MediaFind

MediaFind runs transcription, semantic search, summaries and its Ask assistant on your computer, with no account and no API key. Models download once, then it works offline. A built-in privacy check lets you confirm the core features make zero external connections. You pick models that fit your machine, trading speed for accuracy. See the privacy page and why MediaFind is private by default.

Frequently asked questions

Is on-device AI slower than cloud AI?

It depends on your hardware and the model. Small, well-optimized models can be fast on a modern laptop, while very large models are only practical in the cloud.

Does on-device AI work without internet?

Yes, once the models are downloaded. That is one of the easiest ways to confirm a tool is truly running locally.

Is on-device AI completely private?

The processing is, but check what else an app sends, such as analytics or license checks. A trustworthy tool documents exactly what leaves the device.