Before you choose a model for a task, price it. Pick the kind of task, how often it runs and how much text goes in and out, and see what it would cost each month on today’s leading models. Then see what changes when the routine share of that work goes to a cheaper model.
How to read the numbers
The shortest bar is a starting point. A model that costs a tenth as much is a bargain only if it does your work well enough, and the way to find out is to run 50 to 100 real examples of the task through it. Those examples are worth keeping. Every time a model is repriced, retired or overtaken, they tell you in an afternoon whether the replacement still does the job.
This calculator goes with my article Build for the Change, Not the Model, about why the companies handling AI well build around what they own and rent the models.

