An online polynomial root solver: type one equation per line with coefficients from the highest to the lowest power separated by commas or spaces, so 1 -3 2 means x²-3x+2=0. Choose "All roots" (complex roots are shown as a+bi), "Newton" (give a start value x0 and see x / f(x) / f'(x) for every iteration) or "Bisection" (give a, b and see the midpoint and interval width). The degree is capped at 20 and linear equations are solved analytically; an empty interval or a non-converging run is reported clearly instead of NaN.