Why These Calculators Are Different
Most finance calculators answer the easy question: "What is my monthly payment?" FinToolKit answers the questions that actually change your financial life — the hidden costs, the invisible losses, and the comparisons banks and BNPL companies would rather you never ran.
The money you never see leaving
Interest on loans, stacked pay-in-4 plans, forgotten subscriptions and inflation quietly drain thousands from the average household every year. None of them show up as a single bill, which is exactly why they go unnoticed. Each tool here is designed to make one invisible cost visible — in one screen, with no signup.
Built for everyone, everywhere
All tools support US Dollar, Euro, British Pound, Indian Rupee, Canadian and Australian Dollar. The math is universal: reducing-balance amortization, compound growth, and real (inflation-adjusted) values are calculated the same way worldwide.
Private by design
Every calculation runs entirely in your browser. Your loan amounts, debts, salary and subscriptions are never sent to a server, stored, or shared.