- Litmus: Litmus is a commonly used natural indicator that is extracted from lichens. It changes color in acidic solutions (turns red) and alkaline solutions (turns blue).
- Turmeric: Turmeric is another natural indicator that changes color in the presence of acids (turns red) and bases (turns yellow).
- Red Cabbage: Red cabbage contains anthocyanins that act as indicators. It changes color in acidic solutions (turns red) and alkaline solutions (turns green/blue).
- Beetroot: Beetroot juice can be used as a natural indicator. It turns pink in acidic solutions and yellow in alkaline solutions.
- Blueberries: Blueberries contain anthocyanins that can be used as indicators. They change color in different pH solutions.
- Grape Juice: Grape juice is also a natural indicator that changes color in different pH solutions.

Natural indicators are substances that change color when exposed to acidic or alkaline solutions. They are derived from natural sources such as plants, fruits, and vegetables. These indicators are commonly used in laboratories to determine the pH of a solution. The color change occurs due to a change in the structure of the indicator molecule when it reacts with hydrogen ions (H+) or hydroxide ions (OH-) in the solution. The different types of natural indicators have specific color changes that help in identifying the pH of the solution accurately. These indicators are cost-effective, easily available, and environmentally friendly alternatives to synthetic indicators. They play a crucial role in various scientific experiments and are widely used in educational settings to teach students about acids, bases, and pH levels.