The Appalachian Mountain Club's White Mountain Guide uses a very approximate formula to estimate the time a given hike will take. They calculate 30 minutes for every mile, plus 30 minutes for every 1,000 feet of ascent. Descent is assumed to take as long as walking on a flat trail.

There are obviously a host of other factors involved in determining how long it will take you to do a given hike, but "book time", as this estimate is called, is a popular number. The calculator below (which will only work if your browser supports JavaScript) allows you to calculate book time easily. Enter the elevation gain in the first box, the mileage in the second, and click on the "Calculate" button. The time, rounded to the nearest five minutes, will appear in the last box.


Gain (feet)

Book Time

A more sophisticated (and hence more complex to use) calculator can be found on the NH Hikes and Walks site.