Calcupedia

Beam Deflection Calculator

Construction & Home Improvement

Estimate the maximum deflection of a simply supported or cantilever beam under a point or uniform load.

Ad · Billboard
0.5 ft100 ft
1 lbf500,000 lbf
lbs/ft
1 lbs/ft50,000 lbs/ft
psi
100,000 psi30,000,000 psi
in^4
0.01 in^41,000,000 in^4

Maximum Deflection

0.0750

Maximum expected deflection at the point of greatest movement.

Span-to-Deflection Ratio

1,600

Span divided by deflection, often compared against a code stiffness guideline such as 360.

Share result
Reload calculator
Clear inputs

Found this calculator useful?

From Scratch To $10K/Month In 60 Days

This is a proven money making system that takes students by the hand to make at least $10,000 per month, every month. Students get 12 weeks of guided coaching in addition to the "MPS Super Funnel" and tools.

We value your privacy and promise not to sell or misuse your information. Here's our privacy policy.

Calculator Stats

Odeh Ahwal

Creators

Odeh Ahwal
Reviewed and verifiedThis calculator was reviewed and verified by the Calcupedia due diligence team.

0people find this calculator helpful

Views

Helpful

Saved

Embeds

Like
Share
Embed this calculator
Cite
Save
Ad · 300×250
Ad · 300×250

Frequently Asked Questions

What load and beam combinations does this calculator support?

Four combinations: a simply supported beam with a point load at midspan or a uniform distributed load, and a cantilever beam with a point load at the free end or a uniform distributed load. These are the four most common textbook load cases in beam mechanics.

What is moment of inertia and where do I find it?

Moment of inertia, I, describes how a cross-section resists bending, and depends only on the shape and dimensions of the beam, not the material. For a rectangular section it equals width times height cubed divided by 12; for standard steel or engineered lumber shapes, the manufacturer publishes I directly in their product tables.

Is a lower span-to-deflection ratio better or worse?

A higher span-to-deflection ratio means less relative deflection, so it is generally better. Many building codes reference a minimum ratio, commonly 360, as a stiffness guideline for finished floors.

Spot a mistake? Tell us what's wrong.

Don't see what you need?

Request a calculator. The most-requested ones get built first in our monthly batch.

Request a calculator

Want this calculator on your website?

Embed the Beam Deflection Calculator on any site — no code needed. Customize colors, remove branding, and track usage.

Embed it free →
Embed on any platform — Next.js, React, Vue.js, PHP, Laravel, Shopify, Wix, Webflow, Squarespace, and more