JSFiddle - React, Tailwind, and code Playground

HTML

<input type="number" min="1.01" max="1000" id="num" />

JavaScript

$("#num").on("keyup change focusin focusout", function () {    
    $(this).attr("step", getIncremantal($(this).val()));
});


function getIncremantal(fval) {
    var val = parseFloat(fval);
    var step;
    if (val < 2) {
        step = 0.01;
    } else if (val >= 2 && val < 3) {
        step = 0.02;
    } else if (val >= 3 && val < 4) {
        step = 0.05;
    } else if (val >= 4 && val < 6) {
        step = 0.1;
    } else if (val >= 6 && val < 10) {
        step = 0.2;
    } else if (val >= 10 && val < 20) {
        step = 0.5;
    } else if (val >= 20 && val < 30) {
        step = 1;
    } else if (val >= 30 && val < 50) {
        step = 2;
    } else if (val >= 50 && val < 100) {
        step = 5;
    } else if (val >= 100 && val < 1000) {
        step = 10;
    } else if (val > 1000) {
        step = null;
    }
    return step;
}