The size of the planets in our solar system, starting from the closest to the Sun, are as follows:

Mercury:

- Diameter: Approximately 4,879 kilometers (3,032 miles)

- Volume: Approximately 6.1 x 10^19 cubic kilometers (1.5 x 10^20 cubic miles)

Venus:

- Diameter: Approximately 12,104 kilometers (7,523 miles)

- Volume: Approximately 9.4 x 10^21 cubic kilometers (2.3 x 10^22 cubic miles)

Earth:

- Diameter: Approximately 12,742 kilometers (7,918 miles)

- Volume: Approximately 1.1 x 10^22 cubic kilometers (2.7 x 10^22 cubic miles)

Mars:

- Diameter: Approximately 6,779 kilometers (4,212 miles)

- Volume: Approximately 1.6 x 10^21 cubic kilometers (3.9 x 10^21 cubic miles)

Jupiter:

- Diameter: Approximately 139,822 kilometers (87,501 miles)

- Volume: Approximately 1.43 x 10^25 cubic kilometers (3.53 x 10^25 cubic miles)

Saturn:

- Diameter: Approximately 116,464 kilometers (72,367 miles)

- Volume: Approximately 8.27 x 10^24 cubic kilometers (2.01 x 10^25 cubic miles)

Uranus:

- Diameter: Approximately 50,724 kilometers (31,518 miles)

- Volume: Approximately 6.83 x 10^23 cubic kilometers (1.65 x 10^24 cubic miles)

Neptune:

- Diameter: Approximately 49,244 kilometers (30,600 miles)

- Volume: Approximately 6.25 x 10^23 cubic kilometers (1.51 x 10^24 cubic miles)

Pluto (no longer considered a planet):

- Diameter: Approximately 2,370 kilometers (1,470 miles)

- Volume: Approximately 6.4 x 10^19 cubic kilometers (1.5 x 10^20 cubic miles)

These values are approximate and may vary slightly in different scientific references.