JSFiddle - React, Tailwind, and code Playground

JavaScript

const int = /^[-+]?(?:0|[1-9]\d*)$/ // ints with no leading zeros
const float = /^[+-]?(?:0|[1-9]\d*)?\.\d+$/ // floats with no leading zeros

// some int examples

console.log(int.exec(1234))
console.log(int.exec(-1234))
console.log(int.exec(0))
console.log(int.exec('000001'))  // null

// some float examples

console.log(float.exec(4848.48))
console.log(float.exec(-4848.48))
console.log(float.exec('00.1'))   // null
console.log(float.exec(0.0))      // null
console.log(float.exec(0.0000))   // null
console.log(float.exec(+0.0))     // null
console.log(float.exec(-0.0))     // null
console.log(float.exec('0.0'))    // ["0.0"]
console.log(float.exec('0.0000')) // ["0.0000"]
console.log(float.exec('+0.0'))   // ["+0.0"]
console.log(float.exec('-0.0'))   // ["-0.0"]