7 Best Marine GPS Speedometers – Buying Guide and Reviews

Recording your boat’s speed is a lot of fun but it’s also a great way to keep you safe. It’s always important to know how fast you’re going in different weather conditions. But to track your speed, you’ll need a reliable speedometer.

That’s why we’ve listed the seven best boat speedometers on the market. On top of this, we’ve also gathered some additional information to help you make an informed decision when picking a device. Do you want to learn more about recording your speed?

7 Best Marine Speedometers

The ATACH Digital GPS Speedometer might be the most expensive device on this list but it comes with everything you need. Not only does it have high speed recall memory but it also includes a compass and re-settable odometer. This device is accurate, reliable & can read speeds up to 300mph which is more than enough for any boat.

Here are a few interesting features of this product:

• Display speed: 0-300mph
• Refresh rate: 0.25s
• Back-lit display: White
• Units: km/h.mph or knots
• Includes: total odometer, trip meter & compass

If you’re looking for an affordable speedometer, the Faria 33009 might be the device for you. Although the design is basic, it looks stylish on your boat and the readings are highly accurate. The bezel casing keeps it protected so you can enjoy multiple outings on the water.

Here are some notable features about this product:

• Gauge speed: 10-55mph
• Casing: Black aluminum bezel
• Backlight display: Coral

If you’re looking for a full gauge system, the Sierra International Arctic package includes a:

• Speedometer
• Tachometer
• Voltmeter
• Fuel gauge

With this package, you can keep track of all of your boat’s readings. Sierra’s top of the line technology ensures that you’ll get accuracy for a highly affordable price.

If you want to know some more about these devices, here are their features:

• Speedometer: 0-65mph
• Tachometer: 0-7000 RPM
• 12V Voltmeter: 8-18V
• Casing: Scratch resistant black bezel
• Graphics: Blue & white

The Samdo Universal GPS Speedometer can be used on any type of vehicle and is IP67 waterproof. There’s no need to be concerned with rain or fog. This high precision, low power instrument will stay accurate in all types of weather conditions. It may not be the most attractive but it’s reliable.

Here are all the features of this device you need to know:

• Display speed: 0-160mph
• Working voltage: 9-32V
• Back-lit display: Red

With a LATNEX Waterproof Digital Speedometer, you can take complete control of your speed. This device allows you to set low and high speed alarms so your focus can be on steering. Along with the clock function, this powerful driving speed system helps you feel safer on the water.

Here is everything you need to know about this device:

• Display speed: Max speed
• Refresh rate: 0.2s-0.5s
• Back-lit display: Green
• External power: 10-24V

LeaningTech’s GPS Speedometer can be used immediately. All you need to do is plug it into your cigarette lighter and it’s ready to go. It includes three different viewing modes which enhance its usage flexibility. Because of it’s easy to plug in system, you can use it anywhere.

If you want to know more about this product, here are its features:

• GPS positioning time: One to five minutes
• Input voltage: DC 50-120mA
• Back-lit: Green

The ExGimzmo GPS Speedometer’s excellent anti-fogging and waterproof technology ensures that you can enjoy your boat in any weather conditions. Along with its high precision, it has a quick startup time so it’s ready to go when you are. All you need to do is plug it in.

Here are a few features of this stellar device:

• Display speed: 0-160mph
• Back-lit display: Orange
• External power: 9-32V

Buying Guide

How Does A Boat Speedometer Work?

Most boat speedometers use the speed of the water and air pressure to generate a reading. This works by installing a pitot tube through the boat’s keel. Whenever the boat moves, water is pushed into the tube which compresses the air in the pitot. As the boat’s speed increases, the air pressure builds up as well which gives you a speed reading.

If you’re using a GPS speedometer, it works by calculating how quickly you moved from point A to B. For this reason, GPS speedometers tend to be more accurate and are easier to install.

Different Types of Boat Speedometers:

When looking for a speedometer, there are two types you can pick from: GPS and manual. In our opinion, GPS speedometers are preferable although many people enjoy the classic look of manual ones. We’ve drawn up a comparison to show you why we prefer GPS devices.

GPS Speedometers:

As mentioned before, GPS speedometers record your speed by calculating how quickly you move from one point to another across the water. This is often done by the speedometer connecting with satellites so they can keep track of your location. As a result, GPS systems tend to be more accurate because they’re not obstructed by changes in water currents.

GPS speedometers also have faster refresh rates. Their average refresh rate is 0.25s but it can sometimes be even faster. These devices are also easier to install because they don’t always need to be wired through the entire keel. Occasionally, they can be affected by the weather which means they sometimes lose signal.

Manual Speedometers:

Although manual speedometers aren’t as accurate as GPS ones, they’re still very precise. If you’re traveling over still water, your readings on both devices will most likely be the same. Manual speedometers only tend to be less accurate when there are changes in water currents.

Because they’re recording the air pressure, manual speedometers also have slower refresh rates. Their installation is also a bit more complicated. On the other hand, they look classy once they’re installed and they’re also a lot more affordable.

Imperial and Metric Units:

Although many old fashioned boat speedometers only included either imperial or metric units, many modern ones include dials for both. Digital GPS speedometers will even let you change the type of unit to suit your preference. As a result, you can select either imperial or metric units based on the part of the world you’re in.

Installation:

GPS speedometers are easy to install. If it’s not a simple plug in system, all you need to do is drill a hole into the boat’s instrument panel and connect the wires to an appropriate power source.

If you’re installing a manual speedometer, you’ll first need to mount the device to the instrument panel. When that’s done, you’ll have to route the pitot tube through the keel of the boat. You’ll need to make sure the pitot is securely in place as well before using it.

Final Thoughts:

If you love going out on your boat, you need a high quality speedometer. Tracking your speed means that you can enjoy yourself more on the water but you’re also protecting yourself and your asset.

With any one of these speedometers, you’ll have accurate readings that give you more control over your time on the water. Are you ready for a thrill? It’s better when you can know how fast you’re going.