Sphere Calculator
Sphere V = (4/3)πr³ and A = 4πr². Same engine as Solid Geometry. Not the circle-only page. Not CAS. Runs locally.
Enter values to calculate.
Trust summary CVP VERIFIED · CVP protocol 1.0.0-proposed · Core assurance · all published modes
- Input interpretation
- Enter values to calculate.
- Result
- —
- Verified scope
- all published modes
- Assurance
- Core
- Declared partition coverage
- PASS · 21/21 declared partitions (sphere, cylinder, cone, torus, frustum, prism, pyramid, tetrahedron, octahedron, icosahedron, dodecahedron, regular-prism, regular-pyramid, regular-frustum, ellipsoid, spherical-cap, spherical-zone, spherical-wedge, spherical-lune, spherical-sector, invalid-domain) · Matrix
- Known limitations
- Core CVP does not include live graph, viewport, or pointer interaction.
- Model
- Sphere volume and surface from radius.
- Scope
- Euclidean 3-space
- Verification
- Engine tested · Specification checked · v1.18.0 · CVP VERIFIED · CVP protocol 1.0.0-proposed · Core assurance · all published modes· View Manifest · CVP overview · Specification
- Versions
- Calculation 1.18.0 · CVP protocol 1.0.0-proposed · Evidence 2026-09-21.solid-cvp-all-modes
- Verification revision
- 2026-09-21.solid-cvp-all-modes · 4/4 property · digest d81459afdb09
- Legacy regression
- 118/118 tests · Production surface contract 5/5
- Trust layers
- Verification VERIFIED · Production CURRENT · Overall CVP state: VERIFIED under CVP 1.0.0-proposed
- Reference
- O1 model · O2 expected_values · O2 numerical_behavior
- Interfaces
- PASS · UI (SSR) / REST / MCP
- Supplemental domain review
- Not performed
- Named expert review
- Not performed
- CVP suite
- 26/26 golden · 27/27 CVP boundary · 32/32 invalid · 4/4 property · 8/8 cross-interface · 2/2 cross-calculator · 3/3 CVP contract · Manifest
- Specification basis
- ISO 80000-2:2019 Quantities and units — Mathematics
- Evidence
- 43 legacy golden · 25 legacy boundary · legacy regression suite · 26/26 oracle-backed golden · 32/32 invalid · Artifact integrity PASS
- Semantic contract
- PASS
Full verification
Formulas
Core equations used by this calculator.
How to use
Enter r
Radius must be positive. r = 1 is the unit sphere.
Read V and A
Unit sphere V = 4π/3, A = 4π.
Example calculations
Common configurations with formula and result.
Unit sphere
r = 1
r = 3
r = 3
Sphere calculator specification
Version 1.18.0 · Engine tested
- Engine tested 118/118 tests · Production surface contract 5/5
- Named expert review Not performed
- Calculation version 1.18.0
- Definition
- A sphere of radius r>0 has volume (4/3)πr³ and surface 4πr². This page is mode=sphere on math.geometry.solid. The 2-D circle stays /calc/math/circle. Not a second engine. Not CAS.
- What it calculates
- Sphere volume and surface from radius.
- Inputs
- r
- Outputs
- volume
- surface
- Formula
V = (4/3)πr³, A = 4πr²- Assumptions
- Euclidean 3-space
- The Result Card includes an engine-linked 2-D generating section or silhouette of the published lengths. Not a 3-D mesh. Same pack as REST/MCP.
- Not the circle-only page
- Not CAS
- Units
- length (consistent units)
- volume (length³)
- area (length²)
- Boundary conditions
- r ≤ 0 → VALUE_MUST_BE_POSITIVE
- unknown mode → INVALID_MODE
- Example
- r=1 → V=4π/3
- Validation cases
2 published on this page · 118/118 tests · Production surface contract 5/5 · View evidence
- r=1 → V=4π/3 A=4π
- r=3 → V=36π
- Specification basis
- ISO 80000-2:2019 Quantities and units — Mathematics
- Calculation version
- 1.18.0
Related tools
Other calculators in this family: Cone Calculator, Cylinder Calculator, Dodecahedron Calculator, Ellipsoid Calculator, Frustum Calculator, Icosahedron Calculator, Octahedron Calculator, Prism Calculator . Explore all Solid Geometry.
Frequently asked questions
Key distinctions behind the calculation.
Is this a second solid engine?
No. It is mode=sphere on math.geometry.solid, the same engine as /calc/math/solid-geometry.
Is this the circle calculator?
No. Diameter, circumference, arc, and sector stay on /calc/math/circle.
Where does this run?
Locally in the browser by default. REST and MCP call the same solid-geometry engine.