Calculatorism

3D Geometry: Cone / Sphere / Cylinder / Pyramid Volume & Surface Area

Pick a cone, sphere, cylinder or square-based pyramid, enter radius, height and slant height to get volume, total and lateral surface area.

Input Data

Choose the solid.
Base radius (cone/sphere/cylinder).
Height of the solid.
Square base side (pyramid only).
Slant height; leave blank to auto-compute.

Results

Solid volume.
37.6991
Total surface area (including base).
75.3982
Lateral surface area (excluding base).
47.1239
Formula summary.
圓錐:V=⅓πr²h, l=√(r²+h²)≈5.0000。

At a glance:Cone V=⅓πr²h, sphere V=⁴⁄₃πr³, cylinder V=πr²h, square pyramid V=⅓s²h. Surface areas: cone TSA=πr(r+l), sphere SA=4πr², cylinder TSA=2πr(r+h), square pyramid TSA=s²+2sl, where l is the slant height.

Formula

Cone: V = ⅓πr²h; TSA = πr(r + l); l = √(r² + h²).

Sphere: V = ⁴⁄₃πr³; SA = 4πr².

Cylinder: V = πr²h; TSA = 2πr(r + h); LSA = 2πrh.

Square pyramid: V = ⅓s²h; TSA = s² + 2sl; l = √((s/2)² + h²).

$$V_{\text{cone}} = \frac{1}{3}\pi r^{2}h$$
$$V_{\text{sphere}} = \frac{4}{3}\pi r^{3}$$
$$V_{\text{cyl}} = \pi r^{2}h$$
$$V_{\text{pyr}} = \frac{1}{3}s^{2}h$$

How to Use

  1. Choose the solid (cone / sphere / cylinder / pyramid).
  2. Enter base radius r and height h; pyramid also needs base side s.
  3. Leave slant height l blank (auto from r, h) unless you want to override it.
  4. The tool returns volume, total and lateral surface area; compare with the case studies.

Formulas for the four solids (r radius, h height, s base side, l slant)

Formulas for the four solids (r radius, h height, s base side, l slant)
SolidVolume VTotal SALateral SA
Cone⅓πr²hπr(r+l)πrl
Sphere⁴⁄₃πr³4πr²(no separate lateral)
Cylinderπr²h2πr(r+h)2πrh
Square Pyramid⅓s²hs²+2sl2sl

Cone/pyramid slant height l follows from √(r²+h²) or √((s/2)²+h²).

Case Studies

Cone r=3, h=4

Slant height l = √(3²+4²) = 5.

V = ⅓π·9·4 = 12π ≈ 37.6991.

TSA = π·3·(3+5) = 24π ≈ 75.3982; LSA = π·3·5 = 15π ≈ 47.1239.

Sphere r=3

V = ⁴⁄₃π·27 = 36π ≈ 113.0973.

SA = 4π·9 = 36π ≈ 113.0973 (numerically equal here).

Cylinder r=3, h=4

V = π·9·4 = 36π ≈ 113.0973.

TSA = 2π·3·(3+4) = 42π ≈ 131.9469; LSA = 2π·3·4 = 24π ≈ 75.3982.

Square pyramid s=4, h=3

Slant height l = √(2²+3²) = √13 ≈ 3.6056.

V = ⅓·16·3 = 16.

TSA = 16 + 2·4·3.6056 = 44.8440; LSA = 28.8440.

Cylinder vs Cone (same r, h)

With same base and height, cone volume = ⅓ cylinder volume.

r=3, h=4: cylinder V=113.0973, cone V=37.6991 (= ⅓).

Doubling the sphere radius

r from 3 to 6: volume 36π → 288π (×8, since r³).

Surface area 36π → 144π (×4, since r²).

FAQ

Cone vs cylinder volume?

With the same base and height, the cone volume is exactly ⅓ of the cylinder (Cavalieri's principle) — a common DSE comparison.

What is the slant height l?

The slant height is the cone's generatrix or the pyramid's triangular face altitude, not the solid height h. Cone l=√(r²+h²); square pyramid l=√((s/2)²+h²).

Total vs lateral surface area?

Total surface area (TSA) includes the base(s); lateral (LSA) counts only curved/Slanted faces. A sphere has no separate base, so only total SA.

Must the pyramid base be square?

This tool assumes a square base so a single side s suffices. Other regular polygon bases change base area and face count.

Doubling the radius?

Volume scales with r³ (×8 when doubled); surface area scales with r² (×4). This is the similarity scaling law.

Does the cylinder count two bases?

TSA = 2πr(r+h) includes both top and bottom bases (2πr²) plus the lateral 2πrh. For lateral only use LSA = 2πrh.

Can I use diameter instead of radius?

Inputs are the radius r. If you have diameter d, divide by 2 (r = d/2) first.

What are the units?

Volume is the cube of the input length (e.g. cm³), surface area is the square (e.g. cm²). The tool is unitless — add units yourself.

Related Tools

References

Content review: Calculatorism Science Team. Volume and surface-area formulas for all four solids verified. Results are for reference only.

Found a problem with the results?

If this calculator's result is wrong, or you have any question about the calculation logic, please let us know. You are viewing:3D Geometry: Cone / Sphere / Cylinder / Pyramid Volume & Surface Area/math/solid-geometry)。