how do I (measure boat speed)

  1. Measure my speed in a kayak without having to spend hundreds for a GPS? (Is there some little gizmo that you can hang behind the boat or something?)


You don’t have to spend "hundreds"
Get a Garmin Etrex.

I think you can get one for less than a hundred if you shop for a sale.

They are quite accurate.



Thanks JackL

another early bird huh?


this unit
looks good . Do you have this one? Can you tell me any down sides to it? there is one on e-bay right now for 54 bucks right up the interstate from me.


Let Us Know
If you wind up getting the Garmin. I have looked at the Garmin website and they have some “deals” on some of their products. I would like an inexpensive unit to take occationally just to verify my guess as to how I am doing. Then again, most of my paddling is not at top speed.


there are a bunch on e-bay. Looks like you get only what is installed. no downloads possible etc. should be great for basic navigation. wish it had a built in compass.


It does if you are moving
The GPS has several screens that tell you which way you are going and where north is. The only catch is you have to be moving. As little as 0.2 mph will work. In a canoe on a lake or river it is almost impossible to stop dead anyway so the compass feature is always active.

placed bid
have placed my bid…but still wondering if there is some sort of little gizmo that would measure speed similiar to a pedometer?


Inexpensive Gizmo available for this -
A chart of your local paddling grounds. Use the chart scale to get an accurate distance between two points and use your waterproof wristwatch to time your passage, cause after all, thats sort of the definition of knots. Just don’t drop any zeros when you convert minutes to hours, or your calculated speed will be off by an order of magnitude or so.

I Think There Is A Gizmo
Is it called a ‘speedmate’? GPS does so much more than just speed.

I predict you’ll enjoy your Etrex and upgrade in a year or two.

Yes, there are two downsides…
the read out is very small, and you can’t have both the speed and distance on one window at the same time like you can with the Map 76

For that price, I would get it in a heart beat.



The Etrex has a simulated compass
which is more accurate than a compass. (no lubber line, etc needed).



As mentioned… And Knotstick
they aint hundreds unless you want one that high.

Sailors use the Knotstick also. I have trailed mine behind my boat with the 5 and 10 knot wafer on and measured my speed. Check it out at:

The website is down right now though for some reason.

Google Earth

– Last Updated: Aug-28-05 9:08 PM EST –

Go to and download the free version.

Just time your next paddle, keeping your route along a memorable path. When you get home, just zoom in on your latest paddle location, and use the measure tool (path tab)to retrace your route. You can even switch beteen miles and nautical miles to convert.

~ Arwen ~

Not to be picky, BUT…

– Last Updated: Aug-29-05 9:30 AM EST –

A GPS unit, or timing yourself between two points, measures your speed over ground or "the bottom". A Speedmate or knotstick measures your speed through the water.

If you want to know how fast you're pushing the boat you need to measure your speed thru the water, if you are interested in knowing how fast you are going to get there, you need to measure your speed over the bottom.

Just my 2 cents