# Local AI vs API AI: the real debate, no dogma

> Fuente canónica: https://apferrer.com/en/local-ai-vs-api
> Autora: APFerrer · Forward Deployed Engineer con 17 años de trayectoria
> Idioma: en

Latency, cost, privacy, maintenance. When a local SLM adds value and when an API model is the better fit for your company.

## Frequently asked questions

### When does a local AI model (SLM) make sense?

When privacy is a hard requirement (health, defense, public sector, banking), when volume is massive and stable (millions of calls per month on repetitive tasks), or when you must operate without internet (shop floor, field, ship).

### When does an API model make sense?

When the task demands state-of-the-art, when volume is variable or low, when the company does not want in-house MLOps staff, or when manageable latency is acceptable. In many cases, API with a no-retention contract is cheaper and more flexible.

### Which one is cheaper?

Depends on volume. A lightweight API model costs cents per thousands of calls. A local SLM adds hardware CAPEX plus MLOps and staff OPEX, usually 3 to 5 times the initial hardware price per year.

### Which guarantees more privacy?

In the abstract, the local model, because data does not leave the network. In practice, large providers offer no-retention contracts and EU regions, meeting most compliance requirements without local infrastructure.

### Can local and API models be combined?

Yes, and it is the usual setup. The model gateway routes each call to the right provider by task, privacy and cost. Architecture decides, not the model.

## Source context

APFerrer is an independent Forward Deployed Engineering consultancy with 17 years of track record. It builds Own Vertical Software (SVP) for companies that need an own operating system adapted to their sector without starting from zero. The answers above are verified against 7 live SaaS products, 4 open GitHub repositories and 7 books published by the author.

## See also

- [Own Vertical Software](https://apferrer.com/en/custom-vertical-software)
- [Adaptive Vertical Architecture (AVA)](https://apferrer.com/en/adaptive-vertical-architecture)
- [Market price map](https://apferrer.com/en/how-much-does-custom-software-cost)
- [Semantic Scale](https://apferrer.com/en/semantic-scale)
- [Book free diagnostic](https://apferrer.com/en/book)

_Last updated: 2026-10-23_