What are the disadvantages of litmus and red cabbage juice indicators?

to find out if something is a base or an acid
What are the disadvantages of litmus and red cabbage juice indicators?
They only have two coloured forms - one colour in acid and another in alkali. However they change colour over a certain pH range (5-8 in the case of litmus), so they only tell you if the pH is lower than the bottom end of that range or higher than the top end of that range. Universal Indicator, on the other hand, is actually a mixture of many different indicators which all change colours over different pH ranges, so the mixture goes through a whole spectrum of different colours over a wide range of pH values, allowing you to measure the pH of a solution fairly precisely.

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