When will the alchemist class be freely available? Now I’m trying to create a character, the class is unavailable.
The Alchemist (along with other playable options not available in the Pathfinder primer) will require a purchase for you to be able to use them in the character tools.
You are welcome to use the playable options that are freely available to get a feel for the character tools and how you like them, but in order to use options outside of the Pathfinder primer or the other free adventures, you will need to purchase the sourcebook that they are from. This is the pricing model that Paizo has for all of its official partners (which we are). You are, however, able to get a discount on those books with Paizo Connect, which offers a deep discount on titles that you have as a PDF in your Paizo account. 
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