How to Measure Your Boat for the Perfect Cover Fit
By John Funk, August 05, 2025
Getting a cover for your boat is a simple yet effective way to shield it from harsh sunlight, heavy rains, falling leaves, bird mess, and everyday grime. However, to get the protection you need, it’s important that your cover fits perfectly.
A cover that’s too tight can rip or fail to cover areas properly, while a cover that’s too loose can flap around, collect water, or even blow off in strong winds. That’s why knowing how to measure your boat correctly is crucial before you buy a cover.
Why Measuring Your Boat Properly Matters
Many boat owners assume they can simply buy a cover based on their boat’s make and model.
While some manufacturers do provide covers made specifically for certain models, most covers are sold based on measurements like length, beam width, and sometimes height. I
If you don’t measure the boat for cover correctly, you might end up with a cover that doesn’t fit well, leaving parts of your boat exposed to weather damage or creating pockets where water can pool.
A well-fitted cover protects your boat better, stays in place even on windy days, and lasts longer because it isn’t stressed at the seams. It also makes covering and uncovering your boat easier, saving you time and frustration every time you use it.
Tools You Will Need
Get everything ready first so you’re fully prepared to take accurate measurements. You don’t need anything fancy, just some basic tools like:
- A long measuring tape (preferably flexible and at least 25-30 feet long, depending on your boat size)
- A notebook or phone to note down the measurements
- A helper, if possible, to hold the tape for longer boats
- A step ladder, if your boat is on a trailer, or you need to measure from higher points
Having everything ready will make the process quick and accurate.
Measure the Overall Length
Begin by measuring your boat’s total length, which is the most crucial measurement. Place your tape at the very front of the bow and extend it straight back to the farthest end of the stern. Remember to keep the tape in a direct line over the center rather than following the boat’s curves.
If your boat has an outboard motor and you want the cover to include it, don’t forget to add the motor’s length to your overall measurement.
Some covers come with a separate motor hood, so check the product details to know what’s included.
Don’t measure from the trailer – only measure the boat itself.
Measure the Beam Width
Next, measure the widest part of your boat, which is called the beam. This is usually found around the middle of the boat.
Place the measuring tape across the boat from side to side at its widest point. Ensure the tape goes straight across, not at an angle or following the shape of the boat sides.
Knowing your boat’s exact beam width helps you choose a cover that fully stretches across the boat without being too loose or too tight.
Measure the Height (if required)
Some boat covers, especially custom or semi-custom covers, ask for the boat height. To measure this, place the tape at the highest point of your boat (such as the windshield top or console top) down to the bottom of the keel. If your boat is on a trailer, measure only the boat and not the trailer height.
For most universal fit covers, height isn’t needed, but it’s always good to note it down in case you decide on a tailored cover in the future.
Consider Additional Features
Boats often have features that can affect cover fit, such as:
- T-tops or Bimini tops
- Rails and towers
- Extended swim platforms
- Bow pulpits
If your boat has a T-top, for example, you may need a specific cover designed to fit around the top or include zippers for easier installation. Similarly, if your boat has a swim platform, check whether the cover size accounts for it.
Always read the cover manufacturer’s guidelines for what is included in the listed length range.
Recheck All Your Measurements
Once you’ve measured the length, beam, and height (if needed), write them down clearly. Double-check your measurements by repeating them quickly. This avoids costly mistakes like ordering a cover that is a foot short or too narrow to fit.
Remember, boat covers are usually sold in size ranges (e.g., fits boats from 17-19 feet). Choose the size range that includes your exact measurements without being too tight. If your boat falls between two size ranges, it’s often better to choose the larger size for easier installation and coverage.
Check Manufacturer Recommendations
While your measurements are your primary guide, always check the manufacturer’s sizing chart before buying.
Some covers are designed for specific boat types such as bass boats, bowriders, deck boats, pontoon boats, or center consoles. Choosing the right type ensures a better fit and protection.
If you are unsure, call the manufacturer’s customer support. They can guide you based on your boat’s measurements and features to ensure you get the right cover the first time.
Why Not Guess the Size?
Guessing your boat size or assuming it based on the model can lead to wasted money and frustration. A poorly fitted cover:
- Doesn’t protect your boat properly
- Can flap around and tear during strong winds
- May allow water to pool and seep through the fabric
- Can wear out quickly due to constant tension or movement
Taking just 15-20 minutes to measure your boat for cover accurately can save you the trouble of returning the cover or, worse, dealing with paint damage, rust, or mold caused by poor protection.
Why Choose Seal Skin Boat Covers for Your Perfect Fit
Measuring your boat is important, but with Seal Skin’s semi-custom covers, you might not even have to. Simply provide your boat’s year, make, and model, and we’ll send you a cover already designed to fit it well. No tedious measuring, no guesswork – just a quick and easy way to protect your boat with confidence.
- Designed for a Superior Fit: Seal Skin offers semi-custom and custom-fit boat covers that match your boat’s dimensions closely, ensuring a snug and secure fit without being too tight or too loose.
- Durable, Weather-Resistant Materials: Our covers are made from tough, high-quality materials that protect your boat from harsh sun, heavy rain, snow, wind, and salt spray, keeping it safe all year long.
- Breathable Fabric Construction: Seal Skin boat covers allow moisture to escape while keeping water out, preventing mold, mildew, and corrosion under the cover.
- Easy to Use Daily: With features like elastic hems, built-in straps, and reinforced seams, our covers are easy to put on and remove, saving you time and effort every day.
- Affordable Without Compromise: We offer premium-quality covers at fair prices, giving you better protection and fit than universal covers without the high cost of fully custom marine covers.
Several boat owners across trust Seal Skin to keep their boats protected, clean, and ready for every adventure. After taking the time to measure your boat correctly, choosing a Seal Skin cover ensures your boat gets the protection it truly deserves.
Our products are not just reasonably priced, but we will also ship your order right to your doorstep at no additional cost, without any delay. We offer a full 30-day money-back guarantee and a 10-year manufacturer’s warranty with every purchase.
You can call us at 800-915-0038 during our office hours (Monday to Friday from 9:00 AM to 5:00 PM EST), and we will help you find the right boat cover that fits your needs and budget. We will also help you if you have any questions about our products, shipping policies, and exchange/refund policies.
