Time Calculator (Kilometers per Hour)
If you have not used this
calculator before, please read the text below it first.
Please allow a few seconds for
the calculator to
"Delete" does not work
If you wish to change a figure, just overwrite.
The "bible" for
calculating walking/hiking times has traditionally been Naismith's Rule. This
was devised by one William W. Naismith, a Scottish mountaineer, in 1892. Its
1) Allow 1 hour for every 3
miles walked (equivalent to 4.83 kilometers)
2) Add 1 hour for every 2000
feet climbed (equivalent to 1 minute for every 10 metres)
There have been as many attempts
to "improve" this basic rule as grains of sand. For a start,
Naismith was a very fit mountineer and not everyove walks at 4.83 kph. Over
pavement it might be fine but in the countryside this would be pretty fast,
especially allowing for stiles etc. It does not take account of descents,
either to add time if difficult, or deduct time if an easy slope down which
one can gallop. Then there is the weather, headwinds, driving rain, fog etc
all of which are likely to slow you down. Consultation with various
experienced walkers suggests 3.22 to 4.03 kph is more the norm, so unless you
know for sure you walk faster than this, assume a slower speed to avoid
being caught out.
Essentially, there are too many
variables to make an exact science out of this but Naismith's Rule, with the odd
tweak, is as far as we seem to have got.
With all that in mind, I have
produced the following calculator. This works as follows:
1) Enter the walk distance in
either miles (which will automatically convert) or kilometers - NOT BOTH
The calculation for the first result line assumes Naismith's Rule of 1 hour for every
4.83 kilometers walked and
minutes for any proportion of a kilometer.
2) Total climbing in metres
This is not the summit height and to be accurate, needs to take into account the downs and ups you may
encounter on an ascent. You can assess this from an OS map. The brown
contour lines on a 1:25000 scale map are 5 or 10 metres apart, with heights
indicated. A thicker line appears every 50 metres. However it is quite hard
work. With hindsight, I could have entered the information on each walk, as
I use Memory Map and this automatically provides the information. However,
in producing this calculator, in response to enquiries in November 2016, we
are where we are; as they say. I will include the information in future, at least for
hilly areas and may revise previous walks in time. In the meantime, if you
download the GPX files for the walks then load on
http://bikehike.co.uk via the Course Creator →
Load Routes command, this will give you the information. Maybe consider a
donation to them? My calculation adds 1 minute for every 10 metres if the
normal walking pace is Naismith's 4.83 kph
and more for slower speeds - see item 6) below.
3) Total steep/difficult descent
The calculation adds one minute for every 20 metres, with proportionate adjustment for slower walkers. You really need to
decide here whether the descent is going to make life easy or difficult, or
have little material impact. Often a difficult section might be offset by an
easy section. I suggest if it looks obviously easy, leave the
section blank and treat a speedier finish as a bonus or, if some looks
difficult (say half the descent), just put in a figure for that section.
Please do not use minus figures to denote easy terrain as this will make
figures innacurate for the lower speed categories, see below. An alternative
might be to leave this blank but add some minutes into the Contingency
4) Total Rest/Lunchstops in
This simply adds the minutes you enter.
5) Contingency in minutes
This again simply adds the minutes you enter but is included as a reminder
to consider miscellaneous items.
You could add time for any anticipated issue not covered elsewhere, such as boggy ground,
weather, scrambling, inexperience, time to look at an interesting site etc.
6) What if my normal walk speed is
under 4.83 kph
The results of the calculation
are shown below the entered figures, firstly at the standard Naismith 4.83
it seems to me that if someone normally only achieves a slower speed than
the 4.83 kph, it is probable that they will also need more than the standard 1
minute for every 10 metres of ascent or 20 metres of descent. I have therefore provided the options shown and adjusted the calculation
for ascents in
direct proportion to the longer time taken for walking.
Please note, in the unlikely
event your walk is very long, any times over 24 hours will not show
As stated above, this is
attempting to create an impossible science but any feedback on how effective
these calculations are would be appreciated. I will tweak the figures, if
any quantity of feedback suggests this will improve the calculations.
All information on this
site is given in good faith and no liability is accepted in respect of any
damage, loss or injury which might result from acting on it.