Skip to content
OneKitly
Sign up · Sign in

Cone surface area calculator

Compute the total surface area and slant height of a cone from its radius and height.

Related tools

All Geometry tools →
Surface Area CalculatorTotal surface area of a sphere, cylinder, cone, cuboid, prism, pyramid or tetrahedron.Cone volume calculatorCompute the volume, surface area and slant height of a cone, drawn to scale.Surface gravity calculatorCompute the surface gravity of a planet or moon from its mass and radius.Annulus (ring) area calculatorCompute the area of a ring from its outer and inner radius.Area calculatorCompute the area of a rectangle, square, circle or triangle.Circle sector area calculatorCompute the area and arc length of a circle sector from its radius and angle.Parallelogram area calculatorCompute the area of a parallelogram from its base and height.Trapezoid area calculatorCompute the area of a trapezoid from its two parallel sides and height.

The Cone surface area calculator turns Radius, Height into Total surface area, Slant height, instantly and for free. For instance, with Radius = 3 and Height = 4 it returns Total surface area = 75.398 and Slant height = 5.

How to use it

  1. Enter your values: Radius, Height.
  2. Read the result instantly: Total surface area, Slant height.

Frequently asked questions

How does the Cone surface area calculator work?

It takes Radius and Height and derives Total surface area and Slant height from them. The calculation is live as you type, so the result updates on every change.

Which values does the calculator ask for?

2 values: Radius and Height. Nothing else is required — no account, no file upload.

What does a typical calculation look like?

With Radius = 3 and Height = 4, the calculator returns Total surface area = 75.398 and Slant height = 5. Those figures come from running this exact tool, so you can reproduce them by entering the same values.

How much does the result change with different inputs?

It moves a lot. Using Radius = 6 and Height = 8 instead, Total surface area goes from 75.398 to 301.593 — which is why it is worth testing a few scenarios rather than trusting a single figure.

What does it give for smaller values?

Scaled down to Radius = 2 and Height = 2, Total surface area comes out at 30.338. The relationship is worth checking at both ends before you rely on a single result.

When would I actually use this?

Homework and site work alike: how much paint a wall takes, how much water a tank holds, whether a corner is square — and, on the coordinate side, the slope between two points, the distance across a plan, the midpoint of a span.

What is the most common mistake?

Mixing units inside one shape. Entering a length in centimetres and a width in metres gives an area wrong by a factor of a hundred, and the result looks perfectly plausible.

What is the difference between the Cone surface area calculator and the Surface Area Calculator?

This one returns Total surface area and Slant height; the Surface Area Calculator returns Result. That is the whole difference — open the one whose figure you need.

Is there a tool for the next step?

Cone volume calculator is the closest one after this: Compute the volume, surface area and slant height of a cone, drawn to scale.

What else is worth having open alongside it?

Surface gravity calculator and Annulus (ring) area calculator — they come up in the same task often enough to be worth a second tab.

Further reading

All guides →
How-toCircle: Circumference and AreaCircumference is 2πr, area is πr². Here's how radius, diameter and π fit together, both formulas worked through, and how not to mix them up.ExplainerThe Pythagorean Theorem ExplainedIn a right triangle, a² + b² = c². Here's what the formula means, a worked example, how to find any side, and where it's used in real life.How-toHow to Calculate VolumeVolume is the space inside a shape. Here's how to find it for boxes, cylinders and spheres, and why keeping your units consistent is the whole game.How-toHow to Calculate the Square Metres of a RoomFind a room's area by multiplying length by width. Here's the method for rectangular, L-shaped and round rooms, and why area drives your material orders.ExplainerThe Flat Pattern of a Cone Is a Sector, Not a CircleRoll a 50 mm cone 80 mm tall and its pattern is a 190.8° slice of a 94 mm circle. Flatten a nearly cylindrical lampshade and the pattern radius runs to 839 mm — the shallower the taper, the further away the apex.How-toHow to Find the Area of a Triangle: Base × Height and Heron's FormulaTwo reliable ways to find a triangle's area: half base times height when you know the height, and Heron's formula when you only know the three sides.