How to Measure and Plan a Fence Gate
Plan the clear passage first, then choose a gate product, its post opening, and a swing path that does not hit the yard.
By Fence Planner · 1 min read · Updated 2026-07-20
The short answer
Start with what must pass through the gate. Then choose a gate system and set the posts using that product’s required opening—not simply the width you hope the gate leaf will be.
Why it matters
A gate that clears a person may not clear bins, a mower, or a vehicle. A gate that fits on paper may still swing into steps, a slope, or landscaping.
Do this first
- Measure the widest thing that needs to pass through the opening.
- Choose the gate product before setting posts; its instructions define the post opening and hardware clearance.
- Mark both posts and walk the swing path with string or a board.
- Check the remaining fence sections on both sides of the gate.
Use Fence Planner for this part
Place the gate on its real fence line and compare a few positions. Moving it can make the remaining sections more balanced, even when the total panel count stays the same.
How the estimate works
The planner removes the planned gate opening from the fence fill and splits that side into the sections on the left and right. Moving the gate changes those leftover lengths, so you can compare a few positions before you dig the posts.
Open this gate-position exampleYou will be asked to confirm before anything replaces your current plan.
Educational planning content only. Not a substitute for local codes, surveys, engineering, or professional advice. See Methodology for how this guide was prepared and how the calculator works.