How to test a range of numbers with Jest?

If they are decimal numbers you can use .toBeCloseTo

test('adding works sanely with decimals', () => {
  expect(0.2 + 0.1).toBeCloseTo(0.3);
});

Using methods .toBeGreaterThanOrEqual and .toBeLessThan:

const value = ...
expect(value).toBeGreaterThanOrEqual(lower_inclusive);
expect(value).toBeLessThan(upper_exclusive);