Built a free quarterly estimated-tax calculator for US 1099 / self-employed folks, aimed at the Sept 15 Q3 deadline: https://smeltworks.com/quartertax/
No signup, no email, nothing stored — it does safe-harbor (100%/110% of prior-year liability), self-employment tax, and tells you the per-quarter number and the date it's due. Built it because the existing options either want an account or bury the safe-harbor rule, which is the part that actually protects you from the underpayment penalty.
Feedback welcome, especially on edge cases (multi-state, S-corp salary + distribution mix).
Built a free quarterly estimated-tax calculator for US 1099 / self-employed folks, aimed at the Sept 15 Q3 deadline: https://smeltworks.com/quartertax/
No signup, no email, nothing stored — it does safe-harbor (100%/110% of prior-year liability), self-employment tax, and tells you the per-quarter number and the date it's due. Built it because the existing options either want an account or bury the safe-harbor rule, which is the part that actually protects you from the underpayment penalty.
Feedback welcome, especially on edge cases (multi-state, S-corp salary + distribution mix).