[PopAlongKid]

>Would there be a way to estimate future year taxes?

You can't even always estimate current year taxes, since Congress has lately taken to making retroactive changes to the tax code even after the end of the tax year (just extending their long-term habit of making changes in late December of the current year).

[ideamotor]

Well I’m not looking for 100% accuracy, and it doesn’t need to cover all types of income. I’m interested in long term investment income with various input types of accounts and investments given different inflation and tax policy scenarios. It just needs to be better than the software I’ve seen which is basically trash (assumes a flat percent tax).