Enter the side length of a cube to instantly calculate its volume, total surface area, face diagonal, and space diagonal. All results update live as you type. Choose your preferred unit of measurement below.
Volume: s³ = 5 × 5 × 5 = 125 cm³
Surface area: 6 × s² = 6 × 25 = 150 cm²
Face diagonal: s × √2 = 5 × 1.41421 = 7.071 cm
Space diagonal: s × √3 = 5 × 1.73205 = 8.660 cm
A cube is a three-dimensional solid with six identical square faces, twelve equal edges, and eight vertices. Because all three dimensions (length, width, height) are the same, the volume formula is simply the side length multiplied by itself three times:
V = s × s × s = s³
Where s is the side length in any linear unit. The result is expressed in the corresponding cubic unit. For example, a side of 5 centimetres gives a volume of 125 cubic centimetres (cm³).
A cube has six square faces, each with an area of s². The total surface area is therefore:
SA = 6s²
For s = 5 cm: SA = 6 × 25 = 150 cm². Surface area is useful when calculating materials needed to wrap, paint, or coat a cube-shaped object.
A cube has two types of diagonal:
| Side (cm) | Volume (cm³) | Surface Area (cm²) | Space Diagonal (cm) |
|---|---|---|---|
| 1 | 1 | 6 | 1.732 |
| 2 | 8 | 24 | 3.464 |
| 3 | 27 | 54 | 5.196 |
| 4 | 64 | 96 | 6.928 |
| 5 | 125 | 150 | 8.660 |
| 10 | 1,000 | 600 | 17.321 |
| 20 | 8,000 | 2,400 | 34.641 |
| 50 | 125,000 | 15,000 | 86.603 |
If you know the volume and want to find the side length, take the cube root: s = ³√V. For example, a cube with a volume of 343 cm³ has a side length of ³√343 = 7 cm. You can use the cube root calculator for this.
V = s³, where s is the side length. All sides of a cube are equal, so you only need one measurement.
A cube is a special rectangular box where all three dimensions are equal. A rectangular box (cuboid) uses V = l × w × h. For a cube, l = w = h = s, so the formula becomes V = s³.
The space diagonal runs corner to corner through the cube's interior. Its length is s × √3. For a 5 cm cube, that is approximately 8.660 cm.
Method: Volume = s³. Surface area = 6s². Face diagonal = s√2. Space diagonal = s√3. Standard Euclidean geometry. Source: NIST Digital Library of Mathematical Functions; Coxeter, H.S.M., Regular Polytopes, 3rd ed., Dover Publications.
All calculations use standard Euclidean geometry. Results are exact for integer inputs and rounded to three decimal places for irrational values. This calculator is intended for educational use.
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