# Circle vs. Sphere: What's the Difference?

Edited by Harlon Moss || By Janet White || Published on November 5, 2023
A "Circle" is a flat, 2D shape with all points equidistant from a center, while a "Sphere" is a 3D object with all surface points equidistant from its center.

## Key Differences

A "Circle" is a two-dimensional geometric figure, whereas a "Sphere" is a three-dimensional shape, representing a significant difference in their visual and mathematical properties.
In a "Circle," all points on the line are at an equal distance from the center point, but in a "Sphere," all external points are at an equal distance from the center point in three-dimensional space.
The area of a "Circle" is calculated using πr², while the surface area of a "Sphere" is determined by 4πr², showcasing different mathematical approaches due to their dimensional properties.
A "Circle" is defined by its radius and circumference, while a "Sphere" has a radius, diameter, circumference, and also volume, making the sphere's characteristics more extensive.
"Circles" are often seen in everyday items like wheels, plates, and coins, while "Spheres" are common in balls, globes, and planets, demonstrating their practical applications in various dimensions.

## Comparison Chart

### Dimensions

Two-dimensional
Three-dimensional

### Formula

Area = πr²
Surface Area = 4πr², Volume = 4/3πr³

### Definition

All points equidistant from a center in a flat plane
All points equidistant from a center in three-dimensional space

Wheels, coins
Balls, planets

## Circle and Sphere Definitions

#### Circle

A "Circle" is a perfectly round geometric figure;
The children drew a circle in the sand.

#### Sphere

A "Sphere" can represent many real-world three-dimensional objects;
The planet Earth is a sphere.

#### Circle

A "Circle" exists on a flat plane;
The artist's circle was perfectly flat.

#### Sphere

(Mathematics) A three-dimensional surface, all points of which are equidistant from a fixed point.

#### Circle

In a "Circle," all points on the perimeter are equidistant from the center;
There was a dot in the middle of the circle.

#### Sphere

A spherical object or figure.

#### Circle

A "Circle" can represent many real-world objects;
The moon formed a bright circle in the night sky.

#### Sphere

A celestial body, such as a planet or star.

#### Circle

A plane curve everywhere equidistant from a given fixed point, the center.

#### Sphere

The sky, appearing as a hemisphere to an observer
The sphere of the heavens.

#### Circle

A planar region bounded by a circle.

#### Sphere

Any of a series of concentric, transparent, revolving globes that together were once thought to contain the moon, sun, planets, and stars.

#### Circle

Something, such as a ring, shaped like such a plane curve.

#### Sphere

A range or extent of knowledge, interest, or activity
A problem that falls within the sphere of biophysics.

#### Circle

A circular or nearly circular course, circuit, or orbit:a satellite's circle around the earth.

#### Sphere

A social level or part of society or group
Knew few people beyond his partner's sphere.

#### Circle

A traffic circle.

#### Sphere

A range of power or influence
Within the sphere of the empire.

#### Circle

A series or process that finishes at its starting point or continuously repeats itself; a cycle.

#### Sphere

To form into a sphere.

#### Circle

A group of people sharing an interest, activity, or achievement:well-known in artistic circles.

#### Sphere

To put in or within a sphere.

#### Circle

A territorial or administrative division, especially of a province, in some European countries.

#### Sphere

(mathematics) A regular three-dimensional object in which every cross-section is a circle; the figure described by the revolution of a circle about its diameter . Category:en:Surfaces

#### Circle

A sphere of influence or interest; domain.

#### Sphere

A spherical physical object; a globe or ball.

#### Circle

(Logic)A vicious circle.

#### Sphere

The apparent outer limit of space; the edge of the heavens, imagined as a hollow globe within which celestial bodies appear to be embedded.

#### Circle

To make or form a circle around:The hedge circles the fountain.

#### Sphere

Any of the concentric hollow transparent globes formerly believed to rotate around the Earth, and which carried the heavenly bodies; there were originally believed to be eight, and later nine and ten; friction between them was thought to cause a harmonious sound (the music of the spheres).

#### Circle

To move in a circle around:The ship circled the island.

#### Sphere

(mythology) An area of activity for a planet; or by extension, an area of influence for a god, hero etc.

#### Circle

To move in a circle.

#### Sphere

(figuratively) The region in which something or someone is active; one's province, domain.

#### Circle

(geometry) A two-dimensional geometric figure, a line, consisting of the set of all those points in a plane that are equally distant from a given point (center).
The set of all points (x, y) such that {{(x
R2}} is a circle of radius r around the point (1, 0).

#### Sphere

(geometry) The set of all points in three-dimensional Euclidean space (or n-dimensional space, in topology) that are a fixed distance from a fixed point .

#### Circle

A two-dimensional geometric figure, a disk, consisting of the set of all those points of a plane at a distance less than or equal to a fixed distance (radius) from a given point.

#### Sphere

(logic) The extension of a general conception, or the totality of the individuals or species to which it may be applied.

#### Circle

Any shape, curve or arrangement of objects that approximates to or resembles the geometric figures.
Children, please join hands and form a circle.

#### Sphere

(transitive) To place in a sphere, or among the spheres; to ensphere.

#### Circle

Any thin three-dimensional equivalent of the geometric figures.
Cut a circle out of that sheet of metal.

#### Sphere

(transitive) To make round or spherical; to perfect.

#### Circle

A curve that more or less forms part or all of a circle.
The crank moves in a circle.

#### Sphere

A body or space contained under a single surface, which in every part is equally distant from a point within called its center.

#### Circle

A specific group of persons; especially one who shares a common interest.
Inner circle
Circle of friends
Literary circle

#### Sphere

Hence, any globe or globular body, especially a celestial one, as the sun, a planet, or the earth.
Of celestial bodies, first the sun,A mighty sphere, he framed.

#### Circle

The orbit of an astronomical body.

#### Sphere

The apparent surface of the heavens, which is assumed to be spherical and everywhere equally distant, in which the heavenly bodies appear to have their places, and on which the various astronomical circles, as of right ascension and declination, the equator, ecliptic, etc., are conceived to be drawn; an ideal geometrical sphere, with the astronomical and geographical circles in their proper positions on it.

#### Circle

(cricket) A line comprising two semicircles of 30 yards radius centred on the wickets joined by straight lines parallel to the pitch used to enforce field restrictions in a one-day match.

#### Sphere

The extension of a general conception, or the totality of the individuals or species to which it may be applied.

#### Circle

(Wicca) A ritual circle that is cast three times deosil and closes three times widdershins either in the air with a wand or literally with stones or other items used for worship.

#### Sphere

Circuit or range of action, knowledge, or influence; compass; province; employment; place of existence.
To be called into a huge sphere, and not to be seen to move in 't.
Taking her out of the ordinary relations with humanity, and inclosing her in a sphere by herself.
Each in his hidden sphere of joy or woeOur hermit spirits dwell.

#### Sphere

Rank; order of society; social positions.

#### Circle

(obsolete) Compass; circuit; enclosure.

#### Sphere

An orbit, as of a star; a socket.

#### Circle

(astronomy) An instrument of observation, whose graduated limb consists of an entire circle. When fixed to a wall in an observatory, it is called a mural circle; when mounted with a telescope on an axis and in Y's, in the plane of the meridian, a meridian or transit circle; when involving the principle of reflection, like the sextant, a reflecting circle; and when that of repeating an angle several times continuously along the graduated limb, a repeating circle.

#### Sphere

To place in a sphere, or among the spheres; to insphere.
The glorious planet SolIn noble eminence enthroned and spheredAmidst the other.

#### Circle

A series ending where it begins, and repeating itself.

#### Sphere

To form into roundness; to make spherical, or spheral; to perfect.

#### Circle

(logic) A form of argument in which two or more unproved statements are used to prove each other; inconclusive reasoning.

#### Sphere

A particular environment or walk of life;
His social sphere is limited
It was a closed area of employment
He's out of my orbit

#### Circle

Indirect form of words; circumlocution.

#### Sphere

Any spherically shaped artifact

#### Circle

A territorial division or district.
The ten Circles of the Holy Roman Empire were those principalities or provinces which had seats in the German Diet.

#### Sphere

The geographical area in which one nation is very influential

#### Circle

(in the plural) A bagginess of the skin below the eyes from lack of sleep.
After working all night, she had circles under her eyes.

#### Sphere

A particular aspect of life or activity;
He was helpless in an important sector of his life

#### Circle

(transitive) To travel around along a curved path.
The wolves circled the herd of deer.

#### Sphere

A solid figure bounded by a spherical surface (including the space it encloses)

#### Circle

(transitive) To surround.
A high fence circles the enclosure.

#### Sphere

A three-dimensional closed surface such that every point on the surface is equidistant from the center

#### Circle

(transitive) To place or mark a circle around.
Circle the jobs that you are interested in applying for.

#### Sphere

The apparent surface of the imaginary sphere on which celestial bodies appear to be projected

#### Circle

(intransitive) To travel in circles.

#### Sphere

A "Sphere" is a round solid figure;
The crystal ball was a perfect sphere.

#### Circle

A plane figure, bounded by a single curve line called its circumference, every part of which is equally distant from a point within it, called the center.

#### Sphere

In a "Sphere," all points on the surface are equidistant from the center;
The sphere's surface was smooth and even.

#### Circle

The line that bounds such a figure; a circumference; a ring.

#### Sphere

A "Sphere" has three-dimensional space inside;
The volume of the sphere was calculated for the science experiment.

#### Circle

An instrument of observation, the graduated limb of which consists of an entire circle.

#### Sphere

A "Sphere" has an infinite number of symmetrical axes;
No matter how she turned the sphere, it looked the same.

#### Circle

A round body; a sphere; an orb.
It is he that sitteth upon the circle of the earth.

#### Circle

Compass; circuit; inclosure.
In the circle of this forest.

#### Circle

A company assembled, or conceived to assemble, about a central point of interest, or bound by a common tie; a class or division of society; a coterie; a set.
As his name gradually became known, the circle of his acquaintance widened.

#### Circle

A circular group of persons; a ring.

#### Circle

A series ending where it begins, and repeating itself.
Thus in a circle runs the peasant's pain.

#### Circle

A form of argument in which two or more unproved statements are used to prove each other; inconclusive reasoning.
That heavy bodies descend by gravity; and, again, that gravity is a quality whereby a heavy body descends, is an impertinent circle and teaches nothing.

#### Circle

Indirect form of words; circumlocution.
Has he given the lie,In circle, or oblique, or semicircle.

#### Circle

A territorial division or district.

#### Circle

To move around; to revolve around.
Other planets circle other suns.

#### Circle

To encompass, as by a circle; to surround; to inclose; to encircle.
Their heads are circled with a short turban.
So he lies, circled with evil.

#### Circle

To move circularly; to form a circle; to circulate.
Thy name shall circle round the gaping through.

#### Circle

Ellipse in which the two axes are of equal length; a plane curve generated by one point moving at a constant distance from a fixed point;
He calculated the circumference of the circle

#### Circle

An unofficial association of people or groups;
The smart set goes there
They were an angry lot

#### Circle

Something approximating the shape of a circle;
The chairs were arranged in a circle

#### Circle

Movement once around a course;
He drove an extra lap just for insurance

#### Circle

A road junction at which traffic streams circularly around a central island;
The accident blocked all traffic at the rotary

#### Circle

Street names for flunitrazepan

#### Circle

A curved section or tier of seats in a hall or theater or opera house; usually the first tier above the orchestra;
They had excellent seats in the dress circle

#### Circle

Any circular or rotating mechanism;
The machine punched out metal circles

#### Circle

Travel around something;
Circle the globe

Move in circles

#### Circle

Be around;
Developments surround the town
The river encircles the village

#### Circle

Form a circle around;
Encircle the errors

#### Circle

A "Circle" is defined by the length around its edge;
He measured the circle's circumference with a string.

## FAQs

#### Is a circle the same as a sphere?

No, a circle is flat and two-dimensional, while a sphere is solid and three-dimensional.

#### Can a circle have a volume?

No, circles are two-dimensional and have only area, not volume.

#### How do you find the area of a circle?

The area of a circle is π times the radius squared (πr²).

#### Do circles have edges?

Circles have a boundary called the circumference, but no edges like polygons.

#### Are all points on the sphere's surface the same distance from the center?

Yes, that's the defining characteristic of a sphere.

#### How many faces does a sphere have?

A sphere has one continuous, curved face.

#### What's the formula for the volume of a sphere?

The volume is 4/3 times π times the radius cubed (4/3πr³).

#### Is the Earth a perfect sphere?

No, it's an oblate spheroid, slightly flattened at the poles and bulging at the equator.

#### Can a circle be turned into a sphere?

Through rotation around a diameter, a circle can generate a sphere in three dimensions.

#### What's the line called that goes from one side of the circle to the other through the center?

That's the diameter.

#### Can circles exist in three-dimensional space?

Circles are two-dimensional but can be represented in three-dimensional space.

#### Can a sphere be measured in square units?

Its surface area can, but its volume is measured in cubic units.

#### Is there a point inside a sphere that's not part of it?

No, all points within a sphere's surface are part of the sphere.

That's a sphere.

#### Are there circles in nature?

Yes, you can see them in things like tree rings and ripples on water.

#### Are there perfect spheres in nature?

Natural objects may approximate spheres, but perfect spheres are ideal forms.

#### What's half a circle called?

It's called a semicircle.

#### Is a circle's circumference its perimeter?

Yes, the terms are interchangeable in this case.

#### Is a bubble a sphere?

A bubble typically forms a spherical shape due to surface tension.

#### What's the distance around a circle called?

It's called the circumference.