You can usually tell the difference between a caldera and crater by studying <span>a feature's size and formation. In terms of size, a caldera is often relatively larger than ordinary craters. A caldera is so big that it causes explosive eruptions. In terms of formation, a caldera is a large depression caused when a magma chamber is emptied. A crater is a bowl-like formation at the top of volcanoes where lava comes out.</span>
