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Urban Country Lanes

The How Much Later? Calculator.

The How Much Later? Calculator computes the extension to your travelling time incurred by reducing your speed.
This could be caused by passing through roadworks, getting stuck behind a slow-moving vehicle or slowing down for a hazard.

To use the tool, enter your preferred speed and the speed at which you actually travelled. Then enter either how far or how long you travelled at the reduced speed.
Press Calculate to see the time you lost due to your delay.

How Much Later? Calculator

Optimum speed:
Restricted speed:
Duration:
include time lost while changing speed

Time lost due to reduced speed (hh:mm:ss):
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The inspiration for this tool came from the drivers - frustratingly, mostly parents - who drive at speeds of 35 m.p.h. or more past the school I walk by on my way to work. With all those parked cars, car doors opening and children running out into the road, a more appropriate speed would be 20 m.p.h.
So, what I wanted to know was: how much time do these people actually save by driving too fast and risking the children's lives?

The calculator provides some interesting statistics.
Reducing your speed by a small amount when approaching a hazard costs less time than you may think. And, when you compare this to the time you can spend sitting in traffic jams, you realise just how insignificant the affect of slowing down has on your journey time.
Here are some examples ...

Slowing from 40 m.p.h. to 25 m.p.h. as you travel 200 yards past a school
Time lost:  7 seconds show me
(compare this to the time you'd spend waiting at an accident site for the paramedics/police and filling-out insurance forms)

Adhering to a 50 m.p.h. speed restriction through 5 miles of motorway roadworks
Time lost:  less than 1¾ minutes show me
(compare this to the time you'd spend visiting the Fixed Penalty Payment Office to pay a £60 speeding fine)

Travelling in a slow moving queue for the last 300 yards of a trunk road
Time lost:  over 2½ minutes show me

Crawling for 10 minutes along a congested motorway
Time lost:  over 7 minutes show me

Road Narrows Tool originally created for the TruPlex software web-site, ©2003 Stephen Battey.

Site designed, owned and maintained by Stephen Battey.
©2005, 2006 Stephen Battey
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