How to Measure for a Driveway Gate: The Numbers a Fabricator Needs and How to Get Them Right

Every driveway gate that arrives and does not fit was measured. It was just measured in the wrong place: the old gate instead of the posts, one height instead of two, the concrete instead of the high point of the ground.

This guide is the fifteen minutes with a tape measure that make the gate hang right the first time. You need:

A tapeA helperA phone for photosA pen

What you are actually measuring

A fabricator builds a gate to hang in an opening. The gate itself is narrower than that opening, because the hinges need room on one side and the latch (or the second panel) needs a gap on the other. Those clearances are the fabricator's job. Your job is the opening.

So the single most important number is post to post: the distance between the inside faces of the two posts the gate will hang between, measured where the gate will actually hang. Everything else (height, ground clearance, slope) refines that.

Step 1: post to post, twice

1. At hinge height. Hook the tape on the inside face of one post and run it to the inside face of the other, roughly 3 feet up for a 5- to 6-foot gate. Write it down to the nearest quarter inch.
2. At the top and bottom. Measure again near the top of where the gate will be and near the bottom. Posts lean.
3. Compare. If the three numbers agree within half an inch, use the smallest. If they differ by more, note all three; a leaning post is worth knowing about before the gate arrives, and it may mean resetting it (the posts guide covers when a post is worth saving).

No posts yet? Decide the opening you want (the width guide sizes it by vehicle) and measure between the marks where the posts will stand. The gate's instructions will give you the exact post spacing to set.

Step 2: height

Measure from the ground to the top of the existing posts, or decide the height you want the gate to be. Five to six feet is the residential norm; local rules often cap front-yard gates lower, and the permits guide tells you where to check. Remember that the gate hangs above the ground, so the top of the gate is the gate height plus the ground clearance.

Step 3: the ground under the gate

This is the step people skip and the one that causes the most trouble. Run the tape, or a long straight board with a level on it, across the opening at ground level and note the highest point and the lowest point of the ground the gate will pass over. On a flat concrete driveway they are the same. On a crowned driveway the middle is higher than the edges; on a cross-slope one side is higher; on a driveway that rises toward the house, the ground climbs through the whole swing arc.

Step 4: the swing room

Step 5: photograph it

Take four photos with the tape visible in at least one: from the street looking in, from the house looking out, and each post close up including where it meets the ground. A photo catches what a note misses (the lean, the crown in the driveway, the mailbox that is in the arc) and it is what our assistant uses to check your numbers before you order.

Writing it down

A complete measurement is six lines:

That is everything a fabricator needs. In our configurator you enter the width and height in inches and the price updates for your exact size: a 160-inch gate costs what a 160-inch gate costs, with no stock sizes and no custom premium.

The mistakes that cost people a rebuild

• Measuring the old gate. Covered above, and still the most common one.
• One measurement. Posts lean and openings taper. Three heights, use the smallest.
• Measuring the concrete, not the ground. The gate passes over the lawn and the crown of the driveway, not just the slab under the tape.
• Forgetting the mirrors. A pickup is 6 feet 8 inches at the body and over 8 feet at the mirrors; the width guide has the table.
• Ignoring the turn. A driveway that meets the street at an angle needs a wider opening than the vehicle suggests.
• Guessing the slope. "It's pretty flat" has produced a lot of gates that drag. Put a level on a board.

If your numbers are in hand, they go straight into the configurator. If something above does not match your driveway (an odd angle, a post you are not sure about, a slope you cannot read) send the photos to the gate expert and ask; it will tell you what to measure next.

Related reading: Driveway Gate Posts and Clearance: Wall Thickness, Footing Depth, Spacing and the Gaps That Make a Gate Work · How Wide Should a Driveway Gate Be? Sizes for Cars, Trucks, RVs and Trailers