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Surface Area Calculator

Calculate surface area of cube, sphere, cylinder, cone, and other 3D shapes.

⚡ Instant results🔒 Private — runs locally🆓 Free forever🚫 No signup

Surface Area Calculator

Calculate surface area of cube, sphere, cylinder, cone, and other 3D shapes.

⚡ Instant🔒 Private🆓 Free🚫 No signupMathematically accurate
units
units
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Geometry Formulas

Hypotenuse: c = √(a² + b²) Rectangle Area: A = l × w Circle Area: A = π × r² Circumference: C = 2πr
a, b = Legs of right triangle (or side lengths)
c = Hypotenuse
r = Circle radius
l, w = Rectangle length and width

ℹ️ Pythagorean theorem applies only to right-angle triangles. π ≈ 3.14159

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Disclaimer

Results provided by this calculator are for informational and educational purposes only. They are based on the values you enter and standard formulas, and should not be considered financial, medical, legal, or professional advice. Always consult a qualified professional before making important decisions based on these results. Roughtools makes no warranties regarding the accuracy or completeness of these calculations for your specific situation.

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Frequently Asked Questions

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Pro Tips

1

For percentage calculations, convert the percentage to a decimal first (divide by 100) — this prevents calculation errors: 15% = 0.15, so 15% of 80 = 0.15 × 80 = 12.

2

When working with large numbers, use scientific notation to check your work. A calculator result that's off by a factor of 10 usually means a decimal point was misplaced.

3

Standard deviation close to zero means data is clustered tightly around the mean. High SD means high variability. Always report both mean and SD together for complete information.

4

Cross-check critical calculations with a different method or tool. For geometry, verify with the Pythagorean theorem. For statistics, verify mean with (max+min)/2 as a sanity check.

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When to Use This Calculator

🏗️Construction and DIY

Calculate area for flooring, paint coverage, or fencing before purchasing materials.

🎓Homework and exam prep

Verify calculations and practice working through problems step by step.

🏡Home improvement planning

Calculate room dimensions, wall area, or volume of materials needed for renovation projects.

📐Engineering estimates

Quick calculations for engineering problems where precision is needed before formal computation.

🛒Shopping math

Calculate discounts, percentage savings, or unit price comparisons while shopping.

About the Surface Area Calculator

This surface area calculator computes the total surface area of common 3D geometric solids — sphere, cube, rectangular prism, cylinder, cone, triangular prism, and pyramid — using the appropriate geometric formula for each shape. Select the shape, enter its dimensions, and instantly see the total and lateral surface area with a worked formula. Built for students, engineers, architects, and anyone calculating material requirements for 3D objects.

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How to Use the Surface Area Calculator

  1. 1

    Select the 3D shape from the dropdown (sphere, cube, cylinder, cone, etc.).

  2. 2

    Enter the required dimensions (radius, height, length, width, slant height, etc.).

  3. 3

    See total surface area and lateral (side) surface area instantly.

  4. 4

    Review the formula applied and the step-by-step calculation.

  5. 5

    Switch between metric and imperial units as needed.

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