Notes on calculators, design, and making math feel easy.
Real-time calculation eliminates friction. When users drag a slider, they should see the answer immediately — not after a second click. We rebuilt BMI, Body Fat, and 50+ calculators on this principle.
Read moreDraggable thumbs, spring physics, and smooth bubble tooltips sound simple until you try to make them feel native on both mouse and touch. Here is how we tuned stiffness and damping for a premium feel.
Read moreNo account, no premium, no region lock. We redesigned the entire architecture around local storage and server-side rendering so the app works offline, in dark mode, and in every browser.
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