Use this RV height clearance calculator to check whether your RV fits under a bridge, overpass, or canopy. Enter your RV height and the posted clearance, pick a safety margin, and you see how much room you have and whether it is enough.
How to Use the Calculator
Enter your RV height from the ground to its highest point, roof air conditioner included, in feet and inches. Then enter the clearance from the sign and choose a safety margin. Press Check Clearance to see your result. Not sure how to measure? Our height clearance guide walks you through it step by step, roof items included.
How to Read Your Result
The calculator subtracts your height from the posted clearance and compares the room with your margin. Enough Room means the room is at least your margin, Too Close means you fit with less room than that, and Too Tall means your RV is taller than the sign. The result is a planning guide, so the sign always wins.
Which Safety Margin Should You Pick?
The calculator offers 6 inches, 1 foot, and 2 feet, and starts on 1 foot. Roadtrippers suggests subtracting 6 inches from the posted height, which makes 6 inches the least you should leave. Pick 2 feet for old bridges or when you are not sure of your height.
Signs can be wrong. The Texas DOT sign manual says the measured clearance should be 3 inches greater than the signed clearance, but that is a target and not a guarantee, so do not count on that extra room when you pass.
How to Measure Your RV Height
Park on level ground, put antennas and vent covers in their travel position, and measure from the ground to the highest fixed point with a rigid tape. RecNation Storage says to check separate high spots too, such as a Class C cab overhang. Write the number on a note for the dashboard, and measure again after any roof change.
What Counts Toward Your RV Height
Your height is the tallest point on the roof. That is usually the air conditioner, but check vents, antennas, satellite dishes, solar panels, and roof racks too. Cruise America notes that air conditioners are generally not included in the manufacturer’s stated height, and RecNation Storage says a roof A/C with a satellite dome can add 6 to 18 inches.
How Tall Is an RV?
RecNation Storage lists about 12 to 13.5 feet for a Class A, 10.5 to 12 for a Class C, 6.5 to 9 for a Class B, 11 to 13.5 for a fifth wheel, and 8 to 11 for a travel trailer. These are ballparks, so measure your own rig, which may be taller.
Federal rules set no vehicle height limit, so each state sets its own, and most fall between 13 feet 6 inches and 14 feet, according to RecNation Storage. Individual roads can post lower limits, so the sign on your route always wins.
Why Signs Can Be Wrong
Repaving can cut clearance by about 2 inches each time, according to Roadtrippers, so an older sign may promise more room than you have now. Cruise America adds that there is no guarantee a bridge is remeasured after repaving.
Back roads can be lower still. Roadtrippers points out that many state and local bridges do not have to follow federal clearance rules, especially in rural areas, so a tall RV needs extra care almost everywhere you drive on them.
Beyond Bridges
The same check works for gas station canopies, drive-throughs, and parking garages, which often have no warning sign. Enter the posted height if there is one, or have a passenger step out and look before you pull in.
If the Result Says No
Do not gamble. Stop in a safe place and look for another way around. A detour costs far less than a damaged roof, so take the extra miles.
Use an RV GPS. Regular map apps do not know how tall you are, so enter your height in an RV-specific one. Roadtrippers cautions that even these tools are not 100 percent dependable, so keep watching the signs.
Ask for a spotter. A second set of eyes helps you turn around safely. Our driving guide shows how to agree on hand signals before you start.
Check for damage. If you ever hear scraping, stop right away and look at the roof before you drive on. Small damage is easier to fix when you catch it early.
Your Next Step
Measure your RV once, write the number down, and enter it here each time you plan a route. Our trip planning guide shows how to build the route day by day.