Most tax calculators are either generic (one rate for everyone) or force a signup for something that takes three seconds. DosCifras offers four tools — income tax (IRPF), VAT, net salary and currency conversion — each built on the actual rules of its country: AEAT in Spain, SAT in Mexico, SII in Chile, and more. Every tool cites its official source. No signup, no fine print, instant results. Covers Spain, Mexico, Argentina, Colombia and Chile — and growing. A calculation tool, not tax advice.