Ladder angle calculator
OSHA's 4-to-1 rule sets a safe extension-ladder angle: for every 4 feet of height up to where the ladder rests, place the base 1 foot out from the wall, which puts the ladder at about 75.5 degrees. Enter the height where your ladder touches and get the exact base distance and angle, plus the ladder rules from 29 CFR 1926.1053.
Also remember (29 CFR 1926.1053):
- • For roof or landing access, the ladder must extend at least 3 ft above the landing surface.
- • Secure the ladder at the top, or have it held, so it cannot slip.
- • Keep three points of contact and face the ladder when climbing.
- • Set feet on firm, level ground; never on boxes, mud, or unstable surfaces.
Enter the height where the ladder leans against the wall to get the correct base distance. Nothing you type leaves your browser.
Ladders are a top OSHA construction citation. A verified fall protection and ladder section is part of every safety plan we generate.
Build my safety plan, $49Common questions
▸What is the OSHA 4-to-1 rule for ladders?
For every 4 feet of height up to the point where the ladder rests, the base should sit 1 foot away from the wall. A ladder touching at 16 feet should have its base 4 feet out, which puts it at about 75.5 degrees.
▸How far should a ladder extend above a roof?
A ladder used to access a roof or landing must extend at least 3 feet above the landing surface (29 CFR 1926.1053), and the top should be secured so it cannot slip.
▸What angle should a ladder be at?
About 75.5 degrees from the ground, which is what the 4-to-1 rule produces. Too steep risks tipping backward; too shallow risks the base sliding out.
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