Yantras are primarily used for calculating the positions of celestial bodies, such as planets, stars, and constellations.

The astrolabe is a well-known type of Yantra used in Indian astronomy for measuring the altitude of celestial objects and calculating time.

The Chakra Yantra is a circular diagram that symbolizes the celestial sphere and is used for astrological calculations and predictions.

The quadrant is a Yantra used for measuring the altitude of celestial objects above the horizon.

The Ghati Yantra is a specific type of Yantra used for measuring time intervals and determining the duration of day and night.

The sundial is a Yantra used to determine the exact time of sunrise and sunset based on the position of the sun.

The Bhaskara Yantra is a Yantra designed for calculating the occurrence and timing of solar and lunar eclipses.

The armillary sphere is a Yantra used for studying the motion of planets and their positions in the sky, allowing astronomers to visualize the celestial sphere.

The Yantra Sarvasva is a comprehensive treatise on Yantras, providing detailed descriptions, instructions for construction, and explanations of their astrological and mathematical significance.

The compass is a Yantra used for determining the direction of true north, which is essential for navigation and orientation.

The Jyotisha Yantra is a specific type of Yantra used for creating astrological charts and making predictions based on planetary positions and alignments.

The astrolabe is a Yantra used for measuring the angular distance between celestial objects, such as the sun, moon, and stars.

The Yantra Raj Yantra is considered the most powerful Yantra in Indian astronomy and is believed to possess immense astrological and spiritual significance.

The sundial is a Yantra used for calculating the time of day based on the position of the sun, providing a simple and effective way to tell time.

The Nadi Yantra is a specific type of Yantra used for observing celestial objects, such as stars, planets, and constellations, and studying their movements and positions.