Compute volume and surface area of a regular tetrahedron
Enter edge length to get volume (a³√2/12), surface area (√3·a²), height, inradius, and circumradius. Simplest Platonic solid.
Did our AI summary help? Let us know.
Volume = a³√2/12 — derived from pyramid formula 4 equilateral faces, 6 equal edges One of 5 Platonic solids Height h = a√(2/3), inradius r = a/(2√6) Dihedral angle ~70.53°
Ready to run the numbers?
Why: Tetrahedra appear in chemistry (CH₄, diamond), physics (FEM meshes), and gaming (D4 dice). The simplest polyhedron with 4 faces, 6 edges, 4 vertices.
How: The calculator uses the edge length a to derive all properties. Volume comes from the pyramid formula; surface area from four equilateral triangles.
Run the calculator when you are ready.
Tetrahedron — Simplest Polyhedron
4 equilateral faces, 6 equal edges. V = a³√2/12, A = √3·a².
🔺 Sample Examples — Click to Load
Regular Tetrahedron
Property Radar
Property Comparison
Property Breakdown
📐 Calculation Breakdown
For educational and informational purposes only. Verify with a qualified professional.
🧮 Fascinating Math Facts
Methane (CH₄) has tetrahedral molecular geometry — carbon at center.
— Chemistry
Diamond crystal structure is based on tetrahedral carbon bonding.
— Crystallography
D4 dice are tetrahedral — 4 faces, each with 1/4 probability.
— Gaming
Volume scales with a³ — doubling edge gives 8× volume.
— Geometry
📋 Key Takeaways
- • Regular tetrahedron: 4 equilateral faces, 6 equal edges, 4 vertices
- • Volume | Surface area
- • One of 5 Platonic solids; simplest polyhedron
- • Height , inradius , circumradius
💡 Did You Know?
📖 How It Works
Volume
— derived from pyramid formula V = (1/3)×base×height with equilateral base.
Surface Area
— four equilateral triangles, each with area .
Inradius & Circumradius
Inradius: inscribed sphere touches faces. Circumradius: circumscribed sphere passes through vertices.
🎯 Expert Tips
Unit Consistency
Edge in cm → volume in cm³, area in cm².
Scaling
Volume ∝ a³. Double edge → 8× volume.
Platonic Solid
Only tetrahedron with triangular faces. All edges equal.
Irregular Tetrahedra
For irregular, use scalar triple product with vertex coordinates.
⚖️ Comparison
| Shape | Volume Formula |
|---|---|
| Tetrahedron | a³√2/12 |
| Cube | a³ |
| Sphere | 4πr³/3 |
❓ FAQ
Tetrahedron vs pyramid?
Tetrahedron is a pyramid with triangular base — 4 triangular faces total.
How does edge length affect volume?
Volume ∝ a³. Double edge → 8× volume.
Irregular tetrahedron?
Use scalar triple product of edge vectors. This calculator is for regular only.
SA to volume ratio?
A/V = 12√3/(a√2). Smaller tetrahedra have higher ratio.
Where are tetrahedra in nature?
CH₄, diamond, many viruses, crystals, rock formations.
What is the dihedral angle?
~70.53° (arccos(1/3)) between any two faces.
📊 Stats
📚 Sources
⚠️ Disclaimer: Regular tetrahedron only. All edges equal. Use consistent units.
Related Calculators
Ellipsoid Volume Calculator
Ellipsoid Volume Calculator - Calculate the volume and related properties of an ellipsoid with step-by-step solutions
MathematicsPyramid Volume Calculator
Pyramid Volume Calculator - Calculate the volume and related properties of a pyramid with step-by-step solutions
MathematicsTorus Volume Calculator
Torus Volume Calculator - Calculate the volume and related properties of a torus with step-by-step solutions
MathematicsCube Calculator
Cube Calculator - Calculate volume, surface area, and other properties of a cube with step-by-step solutions
MathematicsSphere Calculator
Sphere Calculator - Calculate volume, surface area, and other properties of a sphere with step-by-step solutions
MathematicsCylinder Calculator
Cylinder Calculator - Calculate volume, surface area, and other properties of a right cylinder with step-by-step solutions
Mathematics