Which model for which job

Stop thinking about brands, start thinking about jobs

New model names arrive constantly, and it is easy to feel you are always behind. You are not. The names change, but the jobs do not. Most of what you will ever ask an AI to do falls into a handful of buckets, and each one has a kind of model that suits it best. Learn the buckets once, and you can pick well for years — whatever the tools end up being called.

The quick guide

Match the job to the kind of model. You do not need to know the brand names — the tool you are using will usually label these, or you can just ask it.

1. 1Everyday writing, emails, chat, quick questions → a fast, general model. Cheap, quick, and good enough for most things.
2. 2Hard thinking — tricky problems, planning, maths, step-by-step logic → a 'reasoning' model. Slower, but it thinks before it answers.
3. 3Working with a long document or lots of text at once → a model with a large 'context window' (it can hold more in mind at once).
4. 4Pictures — making or editing images → an image model. A text model cannot do this, however clever it is.
5. 5Code → a model built for coding, or a coding tool. General models can help, but a specialist is noticeably better.
6. 6Anything private or sensitive → check where your data goes before the model matters at all (see the AI privacy checklist).

When you are not sure, just ask

You do not have to guess. The simplest move is to let the AI itself help you choose.

I want to compare three supplier quotes and work out which is actually cheapest once delivery and support are included. What kind of AI model is best suited to this — a fast general one, a slower reasoning one, one that handles long documents, or something else? Explain your choice in one sentence.

Two rules that save you money and time

1. 1Do not use the biggest, slowest model for simple things. A quick model writes your email just as well and costs a fraction.
2. 2Do not use the fast model for something that needs real thought. If the answer matters and it is complex, pay for the slower one that thinks.