# Boat Distance Calculator

Ian Fortey Updated on December 3, 2021. In Boats

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There are three important parts to planning any trip on a boat when it comes to the journey itself. How fast are you going, how long it’s going to take and how far are you going? You’ll never know when you’re going to arrive somewhere without those numbers. We have a handy boat speed calculator you can use to determine how fast you can travel but that’s only one aspect. Let’s check out what you need to know about calculating boat distances next time you’re on your daysailer.

## Sailing Distance Calculator Formula

Obviously the calculator is a fast and handy tool to make use of. But it’s good to know the math behind how a calculator works, so let’s cover the formula. It’s a very simple one. In a pinch when you can’t use the calculator, you can still do the math in this yourself. These are straightforward formulas.

**Distance = Speed X Time or D = S X T**

With calculations like these you can always solve for any one figure if you don’t know the other two. These formulas can also be used when that’s the case:

**Time = Distance/Speed**

**Speed = Distance/Time**

So let’s try an example to see how it works. Things like this come up when you’re on something like a sailing holiday. You might need to go meet a friend at their marina, for instance. It’s 30 miles away from you. Your boat is able to hit a cruising speed of 35 miles per hour. In this case you have the distance and the speed so you need to figure out time. Time is distance divided by speed.

**Time = Distance/Speed**

Time = 30/35 = 0.857 of an hour

Time = 51 minutes

Remember with all of these that you’re solving for time so you’ll need to multiply or divide by 60 as necessary. That’s just because there’s 60 minutes in an hour. In the above example we multiplied 0.857 x 60 minutes to get roughly 51 minutes.

If you need to know speed let’s say you have 30 miles to go on your route but only 40 minutes until you need to meet your friend.

**Speed = Distance/Time**

Speed = 30/40 = 0.75 x 60 minutes in an hour

Speed = 45 mph

Now we can solve one for distance. You’ve been on your boat for 25 minutes and travelling at 40 mph. It’s easy enough to calculate the distance you’ve travelled as well. This is especially helpful if you don’t have a map or charts handy and haven’t calculated this before.

**Distance = Speed X Time**

Distance = (40 x 25) / 60 minutes in an hour

Distance = 16.6 miles

A Note on Distance

We did miles/miles per hour here. You can calculate these in knots as well. You’ll just want to make sure you convert. 1 knot equals roughly 1.15 miles per hour.

## Why Calculations Matter on a Sailing Holiday

As fun as it is to hit the open water and just go, you can’t do so without a plan. Google Maps only gets you so far. Things like fuel consumption for your yacht trip need to be figured in. The total cost and time to cover X number of nautical miles isn’t something you want to just guess, right?

On the road, you can count on 1,000 other cars and plenty of service stations or roadside assistance no matter what country you’re in. Not so on the water. No matter where you go in the world from Miami to Greece and beyond, you need a plan before you set sail. Planning is what separates good sailors from poor.

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